带英文翻译的给排水论文
带英文翻译的给排水论文2007-07-04 20:03:04| 分类：论文| 标签：大学生论文|字号大中小订阅多层住宅建筑给排水设计的几个问题摘要：本文就多层住宅建筑给排水设计中给水管材的选用，管道的敷设方式，水表出户设置，家用热水器的设置及空调冷凝水排放等问题进行探讨，并提出一些具体看法。
关键词：多层住宅,给水管材,管道敷设,水表,太阳能热水器多层住宅以其配套设施简单，造价低，物业管理方便等特点，很受中小城市房地产开发商和广大居民的欢迎。
如何按2000年小康住宅科技产业工程居住区规划设计导则的要求，提高住宅的设计水平，为每个住户营造出一个舒适的生活空间，是每个设计人员的职责所在。
作为住宅的心脏――厨房、卫生间，是功能复杂，卫生、安全和舒适度要求高，营造繁杂,技术要求高的空间。
因此，设计人员必须以整体设计的观念和方法，综合考虑厨房、卫生间给排水管道和设备的安装等。
下面就多层住宅给排水设计中给水管材的选用、管道的敷设、水表出户设置、家用热水器的设置和空调冷凝水排放等问题与同行们一起探讨。
（一）给水管材选用问题传统的给水管材一般采用镀锌钢管，由于镀锌钢管易锈蚀，使用寿命短，用于输送生活用水不能满足水质卫生标准等缺点，建设部正大力推广塑料给水管的应用。
许多地市已明文规定：禁止设计使用镀锌钢管，推广使用塑料给水管。
塑料给水管与金属管道相比，具有重量轻，耐压强度好，输送液体阻力小，耐化学腐蚀性能强，安装方便，省钢节能，使用寿命长等优点。
给水用塑料管道主要有：硬聚氯乙烯（PVC－U）、高密度聚乙烯（HDPE）、交联聚乙烯（PEX）、改性聚丙烯（PP－R ，PP－C）、聚丁烯（PB）、铝塑复合管（PE－AL－PE，PEX－AL－PEX）和钢塑复合管等。
管材的选择是经济技术的比较过程，技术上应从压力、温度、使用环境、安装方法等方面进行考虑，同时结合业主的要求和住宅的档次，进行经济技术综合考虑后确定。
以上所塑料给水管材都可作为住宅生活给水管材。
经济适用房和解困房主要面对广大中低收入居民，可选用卫生级硬聚氯乙烯管（PVC－U）作为给水管，以降低造价；中高档商品房可用铝塑复合管（PE－AL－PE，PEX－AL－PEX）或其他塑料给水管材作为给水管。
住宅配水点的热水温度不超过600C，因此上述管材中除硬聚氯乙烯管（PVC －U）和铝塑料复合管（PE－AL－PE）外,大多管材可作为住宅的热水管道。
（二）管道敷设问题1．给排水立管的敷设一般有以下几种方式1）明装在厨房、卫生间的墙角处。
在以往的住宅设计中较多采用这种敷设方式，它施工方便，但明露管道有碍居室美观，住户在二次装修时大多会用轻质材料给予隐藏起来。
2）明装在建筑物外墙阴角处。
这种方式仅适用于南方天气较暖和的地区，冬季的最低温度不得低于零摄氏度，以防水管内水冻结成冰，胀裂管道，影响住户使用。
管道在外墙敷设，影响建筑美观，也不便于日后管理和维修。
3）敷设在管道井内。
这种方式使居室洁净美观，但管道井占用了卫生间的面积，且管道施工、维修都比较困难。
卫生间设立集中管道井，把给水管、排水管都集中在管道井里布置，这是小康住宅厨房、卫生间居住文明的重要体现。
本人认为：在中高档的商品房建筑方案设计时应考虑卫生间管道井的设置，这样即提高卫生间的使用质量，又可解决硬聚氯乙烯排水管水流噪声大的问题，提高居室的环境质量水平；对于卫生间面积较小的经济适用房和解困房，在南方较暖和地区给排水立管可考虑敷设在外墙，以增大卫生间的使用空间；管道明装在室内时，应不影响厨房、卫生间各卫生设备功能的使用。
2．给水支管敷设住宅给水支管管径一役de≤32mm，小管径的塑料给水管，呈弯曲状态，故住宅给水支管采用暗设。
给水支管暗设的方式有：1）暗设在砖墙里。
施工时在砖墙面开管槽，管槽宽度为管子外径de+20mm，深度为管子外径de，管道直接嵌入管槽，并用管卡将子固定在管槽内。
2）对于小管径给水支管de≤20mm，可暗设在楼（地）面找平层里。
施工时在楼（地）板面上开管槽，槽宽为de+10mm，深为1／2de，管道半嵌入管槽里，并用管卡将管子固定在管槽内。
铝塑复合管和交联聚丙烯管等管道采用金属管件连接，采用暗设时须加大管槽尺寸，且水流局部水头损失较大。
对于厨房、卫生间内卫生器具布置相对集中的住宅，可采用分水器进行连接，分水器是一种多分支管接头，各卫生器具给水支管分别从分水器接出。
这样既可避免暗埋管道的管接头渗透问题。
又可减小局部水头损失，降低管网造价。
3）排水支管敷设住宅室内排水横管宜设在本层套内，这样排水横管渗透时可避免污水等污染物进入邻户，管道维修时也不会影响到邻户的正常生活。
厨房内洗涤盆的排水横支管一般在本层楼板面上接入排水立管；地漏排水支管须敷设下层空间。
现在许多同行都认为：厨房地面都铺设瓷砖，清洁地在时不须用水冲洗，设置地漏意义不大，故厨房内可不设地地漏，这样既避免排水横支管进入邻户，又可增大厨房的使用空间。
卫生间内排水横支管在本层敷设具体措施有：1）提高卫生间地面。
地面势高150mm，采用后排式坐便器，洗脸盆、浴盆和地漏的排水横管暗埋在垫层内。
2）采用下沉式卫生间。
卫生间楼板面下沉350mm，卫生器具排水横管暗埋在下沉空间里。
这两种做法均可实现卫生间的排水横支管埋设本层的地面而不进入邻户。
暗埋管道安装时，施工质量一定要严格把关，经验收合格后方可施工卫生间地面，以免给日后使用中留下隐患。
卫生间地面施工可填充煤灰等轻质材料，亦可采用砌砖架空铺设制板施工地面，地面须做防水处理，做法可参照屋面防水处理，如做两油一布橡塑油膏防水。
（三）水表户外设置问题水表设在户内，不但抄表的工作量很大，而且使住宅的安全性和私密性大大降低。
故住宅的分户水表或分户水表的数字显示宜设在户外。
多层住宅水表户外设置有以下几种形式：1．采用远传水表把普通水表换成远传水表，由一根信号线连接水表与数据采集机，再传至智能管理（微机）。
它的优点在于节省大量人力来抄表，数据准确，缺点是造价高。
2．采用磁卡式水表用户预先购买自来水公司的电子卡，然后把它插入水表的存贮器内，用水时卡上金额被自动扣除，这种方式用户需预付水费，水表价格较高。
3．采用普通水表设在户外1）水表设在楼梯休息平台的壁龛里。
住户给水支管经水表计量后进入厨房、卫生间。
这种方式实现了水表出房设置，工程等价低，但给水立管和水表设在楼梯处影响美观。
它适用于南方较暖和地区厨房、卫生间布置靠近楼梯间位置的住宅。
2）水表集中设在水表间（水表箱）。
下行上给式供水时，在底层设水表间（水表箱），各层住户给水支管在管道井内敷设，南方地区也可在建筑物阴角处沿外墙敷设；上行下给式供水时，可在屋顶设水表间（水表箱）。
这种方式增加给水支管敷设长度、管道沿外墙敷设影响建筑物美观。
水表出户布置的方式选择，须结合住宅厨房、卫生间平面布置特点和开发商的具体要求，对以上几种可行性方案进行经济技术比较后确定。
物业管理完善的住宅小区的中高档商品房，可采用远传水表，它是今后水表应用发展方向；物业管理不完善的住宅小区的中高档商品房，可采用磁卡式水表（在自来水公司有这种业务的地区可设计）或集中设置水表间（箱）；南方地区单元式住宅可用普通水表设在楼梯的休息平台处，以降低造价。
（四）家用热水器的设置问题住宅设计时应预留安装热水供应设施的条件，或设置热水供应设施。
所以在没有集中热水供应的住宅，应考虑家用热水器的安装位置及冷热水管道布置。
家用热水器一般有燃气、电、太阳能等三种。
燃气热水器和电热水器一般安装在厨房或卫生间内，在建筑给排水设计时应预留出热水器的安装位置和冷热水管道的接口，便于用户装修时自行安装。
太阳能热水器使用简便安全，无需燃料及电力，运行费用低，使用寿命长，无污染，很受广大用户的欢迎，近几年来有不少的住宅小区在设计施工时就全部安装上了太阳能热水器。
太阳能热水器一般安装在屋顶上，这样就需要在卫生间与屋面热水器之间设置冷热水管道，住宅设计时若不考虑太阳能热水器的安装，今后住户安装时只能将冷热管道沿建筑物外墙敷设，这样既增加住户安装时的难度，增加管线投资，又影响建筑的美观。
所以在建筑给排水设计时需要先征求开发商的意见，是否统一设计，统一施工太阳能热水器；或只预留出太阳能热水器及冷热水管道的安装位置。
太阳能热水器的冷热水管道可敷设在管道井内；不设管道井的住宅，可在卫生间靠近沐浴器的墙角增设一根de110的UPVC排水管作为太阳能热水器热水管道的套管，在每户卫生间距地面1m处设一个de110×75三通，作为冷热水管的接入口。
（五）空调冷凝水排放问题近几年，空调逐渐进入千家万户，空调冷凝水无组织排放污染建筑物外墙，已是影响生活区美观的一个重要问题。
建筑给排水设计时应考虑空调冷凝水的有组织排放。
具体做法可在预留空调外机位置旁设置冷凝水排水管，排水立管选用PVC－U排水管de40，在每层空调机高度预留排水三通，便于空调机排水软管直接接入。
The multilevel residential housing is given and drains off water several questions designedSummary: This text give and drain off water on multilevel residential housing design supply water the exertion of the tubular product , Way of laying of pipeline, water gauge produce family set up, establishment and air conditioner condensation water of pot-type boiler discharge issue goes on thediscussion , And put forward some concrete views. Keyword: Skyscraper, supply water the tubular product , the pipeline is laid, The water gauge, the solar water heaterThe skyscraper is simple with its auxiliary facility, the fabrication cost is low, the characteristic such as being convenient of estate management, Receive the welcomes of the real estate developer and vast resident of small and medium-sized cities very much. How project planning and design of inhabited region, scientific and technological industry of comfortable house, lead the request according to 2000, Improve the design level of the house, build out a comfortable living space for each household, It is each designers duty. As the heart of the house --The kitchen, bathroom, is that the function is complicated, hygiene, safe and comfortable degree are expected much, It is miscellaneous to build, the space expecting much in technology. So, the designer must consider synthetically with the idea and method of global design that the kitchen, bathroom give installation of the drainage pipeline and equipment, etc. Give and drain off water on skyscraper design supply water exertion, to lay pipeline of tubular product, water gauge produce family set up, establishment and empty of pot-type boiler now Transfer condensation water discharge issue discuss together with colleagues.( 1), supply water tubular product select problem for use Traditional water supply tubular product adopt zinc-plated steel tube generally, because zinc-plated steel tube exchange the corrosion, Use short-lived , use for and send domestic water can satisfied with water quality sanitary standard shortcoming, Ministry of Construction is popularizing the application of the feed pipe of plastics energetically . A lot of districts and cities have already expressed regulations: Forbid designing and using the zinc-plated steel tube , use widely the feed pipe of plastics. The plastics supply water In charge of compared with metal pipeline, light, it is fine to able to bear the intensity of keeping, Send obstruction little liquid , able to bear chemistry better to corrode performance, it is convenient to install, The steelenergy-conservation of the province, merit of having long performance life etc.. Supply water and use plastics pipeline: Hard polyvinyl chloride( PVC-U), high density polyethylene( HDPE), pay and unite polyethylene( PEX) , modify the polypropylene( PP-R, PP-C), gather butane( PB), aluminum mould and compound and in charge of and the steel is molded and compound and is managed etc.. Choice of tubular product economic comparative course of technology, technology should from pressure, temperature, environment for use, install method ,etc. go on and consider, Combine owners at the same time request and the house of grade, carry on and fix after being consider synthetically technology not economic. The above plastics supply water tubular product can supply water tubular product as house life. The economic and functional house conciliating Strand room in the face of the masses of with low- and medium-level incomes resident, can select for use hygiene grades of hard polyvinyl chloride in charge of as feed pipe mainly, In order to reduce the fabrication cost; Medium-to-high grade commodity apartment available aluminum Mould and compound and in charge of or other plastics supply water the tubular product as the feed pipe. House mix hot water temperature that water order exceed 600 C, so above-mentioned tubular product in charge of except hard polyvinyl chloride and aluminum plastics compound and in charge of( PE-AL-PE), Mostly the tubular product can be regarded as the hot water pipeline of the house.( 2), pipeline lay problem 1. give and drain off water it set up there aren’t one that in charge of 1)Will install it in the corner place of the kitchen, bathroom tomorrow. Adopting this kind of way of laying more in the design of house in the past, it is convenient for it to construct, But will reveal the pipeline and hinder the room beautifully tomorrow Watch, the households will mostly be hidden with the light quality material in the equipment two times. 2)Will install it in the overcast angle place of the outer wall of thebuilding tomorrow. Way this suitable for southern weather warm district only, the minimum temperature in winter cant be lower than zero degrees Centigrade, In case water pipe water-logging freeze ice is bloated to split pipeline, influence household use. Pipeline lay in outer wall, influence building to be beautiful, too inconvenient on manage and maintain in the future. 3) Lay it in the pipeline well. This way makes the room clean and beautiful, but the pipeline well has taken up the area of the bathroom, And pipeline construct, maintain relatively more difficult. Bathroom set up concentrate pipeline well, concentrate pipeline on assign in the well feed pipe, drain pipe, This is that the civilized importance lives in the kitchen of comfortable house, bathroom Embodiment. I think : Should consider the establishment of the pipeline well of the bathroom in the medium-to-high grade building conceptual design of commodity apartment, Improve quality of using of bathroom promptly so , can solve hard polyvinyl chloride drain pipe rivers noise heavy problem, Improve the environmental quality level of the room; Whether for bathroom in the areas for little economic and functional house and Overcome difficulties room, warm area give and drain off water and set up and in charge of and can consider and lay in the outer wall in the South, In order to increase using the space of the bathroom; Pipeline install and in the room, should influence kitchen, bathroom every sanitary equipment use of function tomorrow2. supply water and prop up there aren’t tube House supply water prop up and in charge of pipe diameter one ≤ 32mm, de of battle,, little plastics feed pipe of pipe diameter is the crooked state, S o the house supplies water and is propped up and in charge of being recommended and adopted and set up secretly. Supply water to prop up to manage darkly There are thes way had: 1)Set up in the brick wall secretly. Wall turn on and in charge of trough in brick when constructing, in charge of trough width tube +20 mm, de of external diameter,, degree of depth tube external diameter de, The pipeline is imbedded and managed directly Trough, and with in charge of card fix in trough of inning charge of son. 2)Whether pipe diameter supply water and prop up and last de ≤ 20mm,can set up at floor secretly( ) piece make level by layer. Turn on and in charge of trough in floor( ground) the board when constructing, it wides trough have to be de +10 mm deeply 1/2 of the de, Half pipeline imbed and in charge of trough, and with in charge of card fix in trough of inning charge of tube. Aluminum mould compound and in charge of and pay and unite polypropylene in charge of pipeline adopt metal pipe fittings connection, Must strengthen and in charge of trough size when adopting and set up secretly, and rivers some flood peak loss relatively heavy. Assign the relative house that concentrated to the kitchen, bathroom interior hygiene utensil, Can adopt and divide Water device go on and join , divide water device whether one more than branch in charge of and connect, every hygiene utensil supply water and prop up and in charge of and connects and publishes from the water dividing device separately. Can already prevent the tube burying the pipeline secretly from being connected like this Permeate the question. Can reduce some flood peak lost, decrease the fabrication cost of pipe networks3)Drain off water and prop up the tube to lay House room drain off water and in charge of and should set up at the time of inning this each, drain off water and in charge of permeating sideways like this canning prevent the sewage from waiting for the pollutant to enter the neighbor family sideways, Will not influence the neighbor either when the pipeline is maintained Normal life of one. Kitchen wash water drainage of basin propped up and in charge of generalizing inserts draining off water to stand to manage this layer of floor sideways; Floor drainage off water propped up and in charge of laying the room of lower floor. A lot of colleagues think now: Whether kitchen the ground it lay ceramic tile of, whose name is clean in when need develop with water,not strong in meaning to set up floor drain, So kitchen set up ground floor drain, avoid and drain off water and prop up and in charge of and enter neighbor familysideways already so, Can increase using the space of the kitchen . Bathroom drain off water and prop up and in charge of and lay concrete measure have in this layer sideways inside: 1)Improve the bathroom ground . Ground tendency high 150mm, adopt back row type take stool pot, washing basin, bath tub, water drainage of floor drain in charge of and bury in cushion layer secretly sideways. 2)Adopt the sinking type bathroom. Bathroom sink 350mm the floor, hygiene utensil drain off water and in charge of and bury on sinking space secretly sidewaysTwo method these can realize water drainage of bathroom prop up and in charge of earths surface to bury underground this one without entering the neighbor family sideways. Bury pipeline when installing, construction quality must check on strictly, can construct bathroom ground after confirming qualified secretly, So as not to leave the hidden danger in giving in the future using. Bathroom ground construct and can pack coal ash light quality material , also can adopt and lay bricks impracticable to lay plate making construct ground, Ground must make waterproof to deal with, method can waterproof to deal with according to roofing, make two oil one rubber and plastic ointment waterproof cloth.3), water gauge the open air set up problem The water gauge is had indoors, not only the work load of checking meter is very heavy , but also make the security and privacy of the house reduce greatly . So house divide into households of water gauge or divide households of figure of water gauge Show that should be set up in the open air. Skyscraper water gauge the open air set up following several kinds of forms: Whether 1.adopt far it pass by water gauge Change the ordinary water gauge into and pass the water gauge far, is joined the water gauge and data gathering machine by a signal line, And then reach intelligence to manage( the computer). Its merit lies in saving a large amount of people Strength comes to check meter, the data are accurate, the shortcoming is that the fabrication cost is high. Whether2.adopt magnetic stripe card of by water gauge Users buy the electronic card of the running water Company in advance , then insert it in the storing device of the water gauge, Card amount of money deduct automatically on the water, this way user need to prepay the water rate, The price of the water gauge is relatively high.3. adopt it set up at the open air water gauge not ordinary 1)The water gauge is set up in the stair have a rest in the alcove of the platform. Household watersupply to prop up and manage and enter the kitchen, bathroom after the water gauge is measured. Way this realize water gauge produce room set up, equivalence low project have , supply water and set up and in charge of and set up with water gauge office results in aesthetic problems in stair. It suitable for the South warm district kitchen, bathroom assign close to the houses of positions of staircase. 2)The water gauge concentrates on being set up among the water gauges( meter box). Person who give when supplying water, set up water gauge in ground floor( meter box) on falling, every household watersupply to prop up and is in charge of applying having in the pipeline well, Southern area can overcast horn place lay along the outer wall in building too; Person who give when supplying water, can set up water gauge in roof( meter box) under upgoing. This way increases and supplies water to prop up In charge of and lay length, pipeline lay and influence building to be beautiful along outer wall. Water gauge produce way choice that family assign, must combine house kitchen, bathroom plane assign characteristic and concrete request of developer, Carry on to several feasibility scheme the above economic technology fix after comparing. Propertywell-managed medium-to-high grade commodity apartment of housing district, can adopt and pass the water gauge far , It is that the water gauge will use the developing direction in the future; Estate management perfect medium- to-high grade commodity apartment of housing district, can adopt magnetic stripe card water gauge( Company have this kind district of business can design in runningwater) Or concentrate on setting up it among the water gauges( case); Southern area unit type house can set up rest platform office in stair with ordinary water gauge, In order to reduce the fabrication cost.4) establishment question of the pot-type boiler Should reserve and install hot water supply terms of facility, set up hot water supply facilities with when the design of house. Have and concentrate house that hot water supply on , should consider house assign with installation position and cold hot water pipeline of hot water device. The pot-type boiler generally has three kinds, such as gas, electricity, solar energy,etc.. Whether last kitchen gas heater and electric heater or Bathroom inside, give when draining off water design shoulding reserve installation position and cold hot water interface of pipeline of water heater in advance in building, Install by oneself when convenient users fit up. Solar energy and hot water It is simple and convenient and safe for device to use, need fuel and electric power is low to run the expenses, Have long performance life, pollution-free, received by the masses of users favourably very much, Many houses have been small in recent years The district all install the solar water heater at the time of designing and construct. Solar water heater install and at the roof, need to set up the cold hot water pipeline among bathroom and water heater of the roofing like this generally, Consider installation of solar water heater when the design of house, household can only lay cold and hot pipeline along the building outer wall when installing in the future, Increase household degree of difficulty when installing like this , increase pipeline make the investment, influence building beautiful. Give when draining off water the design needing to solicit the developers suggestion first in building, Interconnected system one design, construct the solar water heater in unison; Reserve solar water heater and cold hot water installation position of pipeline in advance only. The cold hot water pipeline of the solar water heater can be laid In the pipeline well; Set up pipeline house of well , can set up one UPVC drain pipe of de110 as solar water heater hot water sleeve pipe of pipeline close to corner of person who take a shower in bathroom, Set up a de110 *75 three direct links in each hygiene interval ground, as connecting the entry of cold and hot water pipe( 5), air conditioner condensation ink discharge the issue In recent years, air conditioner enter huge numbers of families gradually, condensation water amorphous to discharge the building outer wall of pollution air conditioner have, Have influenced a beautiful important problem of biotope already. Building give when draining off water design shoulding consider air conditioner condensation ink discharge in a organized way. Concrete method can machine set up the water drain pipe of the condensation by the position outside reserving air conditioner, Drain off water and set up and in charge of and select PVC-U drain pipe de40 for use , reserve three direct links of draining off water highly in each air conditioner, It is convenient for air conditioner to drain off water hose insert directly.。
建筑给排水英文文章
建筑给排水英文文章一、IntroductionIn the field of architecture, plumbing systems play a crucial role in providing clean water and removing waste from a building. Effective and efficient building plumbing systems are essential for the health and safety of occupants. This article will explore the various aspects of building plumbing systems, including design principles, materials used, installation methods, and maintenance requirements.二、Design PrinciplesA well-designed plumbing system in a building relies on several key principles:1. Water Supply DesignThe design of a water supply system involves determining the source of water, calculating the required flow rate, and sizing the pipes accordingly. Factors such as building size, occupancy, and water demand must be considered. Additionally, backflow prevention devices are installed to prevent contamination of the water supply.2. Drainage System DesignThe drainage system design focuses on removing wastewater from the building and ensuring proper disposal. Gravity is commonly used to move wastewater through a series of pipes and drains. Proper slope, pipe diameter, and venting are important considerations to prevent blockages, odors, and sewer gas leaks.3. Fixture LayoutThe layout of plumbing fixtures, such as sinks, toilets, and showers, should be carefully planned to optimize water usage, convenience, andaccessibility. Adequate space and accessibility for maintenance should be considered during the design phase.三、Materials UsedVarious materials are used in the construction of plumbing systems. The choice of materials depends on factors such as the type of water supply, budget, and local regulations. Common materials used include:1. PipesPipes are typically made of materials such as copper, galvanized steel, PVC (polyvinyl chloride), and PEX (cross-linked polyethylene). Each material has its advantages and disadvantages, such as durability, cost, ease of installation, and resistance to corrosion.2. Fittings and ValvesFittings and valves connect and control the flow of water within the plumbing system. They are available in materials like brass, copper, and plastic. The choice of fittings and valves depends on the specific requirements of the system and its intended use.四、Installation MethodsProper installation of plumbing systems is crucial to ensure their functionality and longevity. Different installation methods are used depending on the building structure and plumbing system design. Some common installation methods include:1. Traditional Open-Cut MethodThis method involves excavating trenches for the placement of pipes. It allows for easy access and repair but can be time-consuming and disruptive, especially in existing buildings.2. Trenchless TechnologyTrenchless technology, such as pipe bursting and pipe lining, is gaining popularity due to its minimal disruption and cost-effectiveness. It involves using specialized equipment to repair or replace pipes without the need for extensive excavation.五、Maintenance RequirementsRegular maintenance is essential to keep building plumbing systems in optimal condition. Neglecting maintenance can lead to leaks, blockages, and water damage. Some important maintenance requirements include:1. Regular InspectionsPeriodic inspections of the plumbing system can help identify any potential issues before they escalate into costly repairs. Inspections should include checking for leaks, proper drainage flow, and functioning of valves and fixtures.2. Clearing BlockagesBlockages in drains and pipes should be promptly cleared to prevent backups and plumbing system failures. This may involve using mechanical tools or chemicals, depending on the nature of the blockage.3. Water Heater MaintenanceWater heaters should be inspected and serviced regularly to ensure efficient and safe operation. This includes checking for leaks, sediment buildup, and testing the pressure relief valve.六、ConclusionBuilding plumbing systems are vital for the functionality and comfort of a building. Proper design, choice of materials, installation methods, and regular maintenance are key factors in ensuring the performance and longevity of these systems. By following the principles discussed inthis article, architects, engineers, and building owners can createreliable and efficient plumbing systems that meet the needs of occupants while adhering to relevant regulations.。
排水专业英语作文
排水专业英语作文Drainage Systems: The Unsung Heroes of Our Cities。
You know, drainage systems are like the silent guardians of our cities. They're always there, working hard to keep our streets and homes dry, but we hardly ever notice them. And that's okay, because they don't mind the lack of recognition.When it rains, you can bet your bottom dollar that the drainage system is on the job. It's like a giant network of underground highways, carrying water away from ourbuildings and streets. And if it weren't for these guys, we'd be dealing with floods every time there's a little bit of rain.Did you know that drainage systems are actually pretty complex? There's a lot of engineering involved in making sure they work properly. It's not just a matter of digging a few holes and connecting some pipes. There's a science toit, and it's fascinating.One thing I love about drainage systems is how they're always evolving. With new technology and materials, we're able to design more efficient and sustainable systems. It's like they're getting smarter and stronger every day, andthat's a good thing for all of us.So, the next time you're out and about and it starts to。
给排水工程屋顶排水中英文对照外文翻译文献
中英文对照外文翻译(文档含英文原文和中文翻译)Short and Long Term Advantage roof drainage design performance Decade has witnessed great changes in the design of the roof drainage system recently, particularly, siphon rainwater drainage system has been gradually improved, and there is likely to be the key application. At the same time these changes, urban drainage system design has undergone tremendous changes, because the scope of a wider urban drainage system design for sustainable development, as well as people for climate change flooding more attention. The main contents of this article is how to design roof drainage systems and make a good performance. Special attention is how to get rid of bad habits already formed the design, but also need to consider innovative roof drainage system, such as green roofs and rainwater harvesting systems.Practical application: In the past few years, the design of the roof rainwater drainage system has undergone tremendous changes. On large buildings, siphon rainwater drainage technology has been very common, as well as green roofs because it is conducive to green development, being more and more applications. Taking into account the ongoing research, this article focuses on how to effectively design a variety of roof rainwater drainage system, and make it achieve the desired design effect.1. IntroductionIn the past decade, the city and the water drainage system design has been widely accepted thinking about sustainable urban drainage system, or the optimal management direction. The main principles of the design of these systems is both a local level in line with the quality of development, but also to create some economic benefits for the investors. This principle has led to the development of new changes in the sump. Although the application of such a device isgradually reduced, but the urban environment relatively high demand areas still require 100% waterproof and rapid drainage, such as the roof. Typically roof drainage system in the design, construction and maintenance has not been given due attention. Although the drainage system investment costs account for only a small portion of the total construction investment, but not able to judge the loss caused by poor design.There are two different forms of roof drainage system design methods, namely the traditional and siphon method. Traditional systems rely on atmospheric pressure work, the drive ram affected sink flow depth. Therefore, the conventional roof drainage systems require a relatively large diameter vertical drop tube, prior to discharge, all devices must be connected to the groundwater collection pipe network. In contrast, siphonic roof drainage pipe systems are generally designed to full flow (turbulent flow means that require less exhaust pipe), which will form a negative pressure, the larger the higher flow rate and pressure head. Typically siphon system requires less down pipe work under negative pressure to the water distribution network can mean higher altitude work, thereby reducing the amount of underground pipe network.Both systems consists of three parts: the roof, rainwater collection pipes, pipe network.All of these elements are able to change the water pressure distribution system. This section focuses on the role and performance of each part. Due to the principle of siphon system has not been well understood, resulting argument is relatively small, this article will highlight siphon system.2. RoofThe roof is usually designed by the architect, designer and not by the drainage design. There are three main roof.2.1 Flat roofFlat roofs are used in industrial buildings less rainfall regions and countries. This roof is not completely flat, but lower than the minimum roof slope may require. For example, the United Kingdom require maximum slope of 10 °. Setting minimum slope in order to avoid any unnecessary water.Despite the flat roof if it is not properly maintained will have more problems, but it will reduce the dead zone within the building, and the ratio of sloping roofs in favor of indoor air.2.2 sloping roofsMost residential and commercial buildings are pitched roof, inclined roof is the biggest advantage can quickly drain, thereby reducing leakage. In temperate regions, we need to consider carrying roof snow load. Once it rains, rainfall through the sloping roofs can be determined by calculation. When rainfall data can be used, you can use the kinematic theory to solve such problems.2.3 green roof (flat or inclined)It can prove roof is the oldest green roofs, including rainfall can reduce or disperse roof planted with plants. It can be planted with trees and shrubs roof garden, it can also be a vegetated roof light carpet. Wherein the latter technique has been widely used. Some of these applications tend to focus on aesthetic requirements and are often used in green development. Since the aesthetic requirements and pressure requirements, as well as green roofs thermal insulation function, reduce the heat island effect, silencer effect, extend the life of the roof.Green roofs in Germany, the most widely used, followed in North America, but to consider the impact on the aesthetics. Germany is by far the most experienced countries in the 19th centuryhave practical application, then as an alternative to reduce the risk of fire tar roof an option in urban areas. Germany is currently the main research question on the cultivation of other issues to consider smaller cities. A study from 1987 to 1989, was found packed with 70 mm thick green roof can be reduced by 60% -80% of heat loss. In a Canadian work computer model based on the roof indicates that as long as the sump, the area can reach 70% of the roof area can be reduced by 60 percent in one year, the same model was also used for artificial rainfall, which the results indicate that rainfall in the catchment season helps to drain away rainwater.However, none of these studies show that green roofs can play a useful role in the rainfall season, or how high collection efficiency of water supply. The United States did some tests, as long as the green roofs regular watering, can reduce 65 percent of the runoff in a rainfall. America's most authoritative green roof guidelines by the New Jersey state environmental agencies promulgated. The main principle is to solve the structural problems of light, and how can the normal drainage after two years.Rainfall period is based on the probability of failure is determined. The system is typically based on rainfall during rainstorms two minutes, two minutes, have a choice. Although this model will get more traffic, but there is no other better alternative. Studies have shown that the traditional model is applied to study green roofs are premature.Loss factor than traditional roof records should be small, about 98.7%.Peak flow will be reduced, although not penetrate, the surface roughness but also have a significant impact.Concentrated rainfall than two minutes for a long time, especially for large roof areas, such as public buildings, commercial buildings, industrial buildings.Urban drainage design should also consider other factors, for a complex system, a green roof in a rain is not enough. Water flow duration curve shows a longer than traditional systems. And two independent and will affect between is possible, which requires a more precise time period. 3. Rainwater CollectorBasic requirements rainwater collector is designed to be able to accommodate rainfall rainstorms. Although it is possible to make a slightly inclined roof drainage purposes, but the nature of the construction industry and building settlement will become flat roof Typically, the tank is placed in a horizontal, sectional view of the water is outwardly inclined, which the role of hydrostatic.3.1 drain outletAnalyzing rainwater collector has sufficient volume is the key to the sump outlet external setting conditions. Also affect the flow rate into the storm water drainage system piping, but also affect the depth of the water catchment. Although the depth of the sump will not bring any particular problems, but too deep can cause excessive sump.Numerous studies in the 1980s showed that the flow of conventional roof drainage system outlet can be divided into two cases. It depends on the size of the depth and size of the outlet. When the water depth is less than half the diameter of the outlet, the flow of the first type, and the outlet of the flow can be calculated by an appropriate equation; water depth increases, exports are slowly clogging the flow will become another form forms, at the same time, the flow of exports can be obtained through other equations. While conventional roof drainage systems are designed to be free-draining, but may cause limitations encountered in the design of the flow is not free. In this case, it will require additional depth.Siphon roof drainage systems, the outlet is designed to be submerged stream. In this case, the depth of the outlet of the decision is more complicated, because the design of the sump depends on the flow. Recent studies have shown that conventional roof drainage systems use a variety of non-standard catchment, their depth and height, bigger than the diameter of the outlet. This will eventually result in a siphon effect. For a given catchment, the flow depends on the starting end of the drop tube diameter. A similar phenomenon has also been used to study the standard catchment, in these circumstances, only limited siphon action occurs within relatively close distance from the exit.3.2 tank flow classificationIn the complex flow sump outlet flow classification, can be seen from Table 2a, the flow will be uniform layering, regardless of whether the same inlet flow. Table 2b and 2c show, export distribution will greatly influence the flow.When the outlet is not a free jet, sump outlet complex flow classification is difficult to describe. Because each catchment tank pressures are likely to be merged. For example, the siphon tube system design point is at near full jet outlet flow classification depends on the energy loss of each branch.3.3 hydrostatic sectionalSump shape of the water surface in the canal can be classified according to the flow equation. In most cases, a low flow rate means that there is less friction loss, if exports are free jet, the friction loss is negligible cross-section through the hydrostatic equation 1 to determine the horizontal distance.Where Q-- flow (m3 / s)T- surface width (m)g- acceleration of gravity (m / s2)F- flow area (m2)Equation 1 can not be ignored when the friction required to correct (or very long pipe velocity is large), or not a free jet.3.4 The current design methodsThe previous discussion has highlighted the main factors that should be considered with sink design. However, without the help of a certain number of models, computing hydrostatic sectional roof drainage system, the volume of the sump is possible. This large commercial and manufacturing industry, is a development opportunity, you can merge several kilometers of water routes. Thus, the conventional drainage system sump design methods are mainly based on experience, and assume that exports are free jet.Sump location in the building, it may cause the example to fail.Different interface sumpExcept in the case cited above, but also allows designers to use empirical data.3.5 Digital ModelLarge number of digital models can be used to accurately describe the flow of any form of catchment tank, regardless of whether the roof flows stable. An example of this model is a combination of roof space model. This model enables users to classify different aspects of the data indicated, includes: details of the rains, the roof surface drainage and other details. Kinematics have also been used to study rainwater tank to flow from the research collection. A typical method is based on open system to solve a basic problem of spatial mobility. This model automaticallyresolve the sump outlet flow situation, but also to deal with the case of free jet can also be simulated space limited mobility and submerged discharge. Output values include depth and flow rate.Currently, the model is essentially just a variety of research tools, but also through practical engineering test. However, we should face up to the various role models.4 pipe systems groupComposition in the form and scope of the tube group determines the roof drainage system relies mainly on the traditional system or siphon action.4.1 Traditional stormwater systemsConventional roof drainage systems, the ground plane is generally vertical pipe-line network, connected to the sump outlet and underground drainage systems, critical systems as well as compensating tube. It should be emphasized that the angle between the ground and the compensating tube is less than 10 °. Capacity of the entire system relies mainly on the outlet tube instead of down.Flow vertical tube is usually free-flowing, full of only 33%, the efficiency depends on the excess length of the tube. If the drop tube long enough (typically greater than 5m), there may be an annular flow. Similarly, under normal circumstances flow compensation pipe is free-flowing, full of up to 70%. Such designed process both for the design, various equations can also be used.4.2 Siphon roof drainage systemIn contrast with the traditional drainage systems, Siphon roof drainage system relies on air flow outside the system, and the tube is full pipe flow stream.The designs are usually made on the assumption that the design of heavy rain, the system can quickly siphon discharge rainwater. This assumption allows the application of hydrostatic siphon system theory. Often used steady flow energy equation. While this approach ignores the small amount of energy loss at the entrance, but after the experiment showed that there are still conducive to practical use.However, steady-state design methods in the siphon system is exposed to rain when the system does not meet the standard requirements or changes in rainfall intensity is large is not applied. In the first case, there will be some mixing of air quality, annular flow occurs. These problems are not integrated in the system when more serious. Because usually designed rains are common, it is clear now design methodology over time may not apply to siphon system. This is a major disadvantage, because the design of the main problem is the noise and vibration problems.Despite the disadvantages of the prior design approach, but a lot of the world's very few engineering failure reports. When a failure occurs, most likely for the following reasons: An incorrect understanding of the operation pointsSubstandard materials listInstallation defectsMaintenance mismanagementTo overcome these disadvantages, we have recently launched a series of research projects, to discuss the siphon system, and the development of digital models. From this work we learn a lot. In contrast with conventional design methods of some assumptions, siphon system mainly has the following aspects:1) non-flow system of full flow2) levels of certain pipe-flowing full pipe flow3) full pipe flow downstream propagation through a vertical pipe, riser, etc.4) the inner tube flow occurs over the vertical section, the system to reduce the pressure5) downward tube is full pipe flow, there will be air lock6) appears completely siphon action until well into the air system is lower than a certain levelTable 4a column data indicate that below the design point, the system will siphon unstable flow, depth of the water collecting tank is insufficient to maintain the siphon action. Table 4b show that the unsteady flow in siphon system when it will appear.Table 5 lists the data output of a digital model. It can be seen that the model can accurately describe the siphon action, siphon and steady state, the data also show that the model can accurately describe the complex siphon action.5 ConclusionThis article has illustrated the critical roof drainage systems, but these are often overlooked in the urban drainage system design. This article also shows that the design process is a complex process, rely mainly on the performance of exports. The following conclusions are based on the design summed up:1) Run depend on three interacting parts: the roof, sump, water pipes2) Green roofs can reduce traffic and beautify the city3) the export performance of the system is essential4) siphon drainage system have a greater advantage in large-scale projects, but must be considered high maintenance costs5) Design siphon drainage system should consider additional capacity and operational issuesAlthough the green roof is a more attractive option, but the traditional roof of a building in the country will continue to dominate. Green roofs will be gradually developed, and gradually been widely accepted. Similarly, the roof drainage system shown effective that it will continue to play a huge role in the commercial building drainage systems.Roof drainage system of the greatest threats from climate change, existing systems tend to be not simply aging; rainfall patterns of change will result in inefficient operation, self-cleaning rate will be reduced. Changes in wind speed and the roof will also accelerate the aging of the roof, it is necessary to carry out maintenance. Taking into account the climate change, the increase in materials, roof collected rainwater will be more extensive. Currently, the amount of rain around the globe per person per day 7-300 liters in the UK, with an average consumption of 145L / h / d, of which only about one liter is used by people, about 30 per cent of the toilet, study shows If water shortage, rainwater collected on the roof of developed and developing countries are recommended approach.屋顶排水设计性能的近期与远期优势最近十年见证了屋顶排水系统设计方面的巨大变化，特别的是，虹吸雨水排水系统已经得到逐步改善，并且有可能得到重点应用。
给排水工程专业饮用水水质问题及对策大学毕业论文外文文献翻译及原文
毕业设计（论文）外文文献翻译文献、资料中文题目：饮用水水质问题及对策文献、资料英文题目：文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：给水排水工程班级：姓名：学号：指导教师：翻译日期： 2017.02.14毕业设计外文文献翻译学生姓名：学号：所在学院：专业：给水排水工程论文题目：Drinking Water Problems andSolutions Abstract指导教师：2007 年6月15日Drinking Water Problems and Solutions Abstract1 Introduction：Chlorination oxidation Introduction nearly half a ce ntury, the world economy has been developing rapidly, modernizationof industries, in particular synthetic chemical is used. Thesechemicals through most of human activities into a body of water, such as sewage and industrial wastewater discharges Agricultural use of fertilizers, pesticides wastage so that the water body accepted the physical and chemical traits a significant change [1]. Early 1980s found that more than 2,000 water organisms, water is more than 700, Among them, 20 kinds of carcinogens, suspected carcinogens 23 species, 18 species of croton oil, and 56 kinds of mutagens [2]. Now the world has attached great importance to trace organics pollution and human health.Currently many of the world's developing countries for drinking water purification methods, basically conventional coagulation sedimentation → → → sand filter chlorine disinfection process. This process for clarifying water to eliminate pathogens in water is very effective. After generally considered the conventional process, filter water after E. coli bacteria and infectious diseases such as HIV have access to basic removal. But with the water pollution, the intensification of a wide variety of organic matter into a body of water formed real solution, the conventional process is almost powerless. China's GB5749-85 "standard of drinking water" [3] Water detected a total of 35 projects. EC Directive provides drinking water were 66, the World Health drinking water regulations is 47. Compared with China, mainly to the increase in the trace organics project. Organic pollution of the drinking water situation, we must find new approaches.2 Commonly used method of disinfection of water treatmentIt is low cost, simple equipment, operation and management easy. But with the water chlorination of organic reaction occurred replace skull organic compounds, the so-called "three to" material, right, poses a potential human health hazards.1970s, the Netherlands and the United States found that treatment workers, chlorination, drinking water produced trihalomethanes (TCM) compounds, mainly chloroform,dichloroacetic acid, chlorine and bromine between the intermediate product. After the chlorination of drinking water has not only generated three skull methane, but also generate other skull Organics (TCO), concentration of TCM general concentration of 5 ~ 10%, which on human health have the same adverse effects [4]. TCM TCO and the main precursorof the three major categories : ①wreckage from the plant as a result of humic acid and fulvic acid degradation products, such as resorcinol, homovanillic acid and fulvic acid degradation products; ②algae from the pyrimidine amino acid, tryptophan, proline, uracil, protein; ③ industrial wastewater of certain compounds, such as phenols. Use chlorine to disinfect TCM TCO and the emergence of awareness of the existence of the hidden danger. Thus, non-chlorine disinfection technology research to develop rapidly.3 measures and the development trend [5] to solve the drinking water problem of pollutionthere are two ways : ①protection of drinking water sources;②strengthen water treatment processes. Generally speaking, the quality of our water environment is also hard to improve short period of time. To the increasing demands for drinking water, water pollution from access to quality drinking water, alternative method is to strengthen the water treatment process that uses advanced deep water treatment technology. Is briefly described below4 ConclusionClosing above the new water treatment technology now have their own shortcomings, to be further explored and examined. If UV-ozone and UV-CO2 is the most promising of the two photochemical oxidation, desire of the family or group users of drinking water depth and special treatment of organic wastewater treatment play an important role. UV-O3 combinedtechnique has been USEPA (EPA) to address the identification of multiple chlorobenzene the most effective technology. But the process in the current obstacles to the use of CO2 is separated from the water, choose a suitable carrier and fixed method, preparation or other forms of photo-catalyst, and research and development of photochemical oxidation and water needs to deal with the combination of UV light or metal skull of lights, so power, wavelength suitable and convenient. Membrane operate with convenience, good effect, but easy to silting and pollution, with its investment and operating costs are too high. KMnO4 and ozone oxidation, often generate many intermediate products, and even some organic fundamental ineffective. Therefore, in recent years more and more emphasis on the treatment of workers in physical, chemical, biological purification organically combine bold attempt, Research such as O3 - H2O2 - BAC, O3 - coagulation-activated sludge, KMnO4 - BAC O3-UV-H2O2, O3-film processing, O3-stripping and other possible joint technology, give full play to their respective means of the technical features and advantages of comprehensive management, in order to achieve the best removal.饮用水水质问题及对策1 引言近半个世纪以来，世界各国经济迅速发展，现代化工业，尤其是合成化工业更是突飞猛进，这些化学物质的大部分通过人类活动进入水体，如生活污水和工业废水的排放，农业使用化肥、杀虫剂的流失等，使接纳水体的物理化学性状发生了显著的变化〔1〕。
给水排水中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：Optimum combination of water drainage,water supply and eco-environment protection in coal-accumulated basin of North ChinaAbstract The conflict among water drainage,water supply and eco-environment protection is getting more and more serious due to the irrational drainage and exploitation of ground water resources in coal-accumulated basins of North China.Efficient solutions to the conflict are tomaintain long-term dynamic balance between input and output of theground water basins,and to try to improve resourcification of the mine water.All solutions must guarantee the eco-environment quality.This paper presents a new idea of optimum combination of water drainage，water supply and eco-environment protection so as to solve theproblem of unstable mine water supply,which is caused by the changeable water drainage for the whole combination system.Both the management of hydraulic techniques and constraints in economy,society,ecology,environment,insustuial structural adjustments and sustainable developments have been taken into account.Since the traditional and separate management of different departments of water drainage,water supply and eco-environment protection is broken up these departments work together to avoid repeated geological survey and specific evaluation calculations so that large amount of national investment can be saved and precise calculation for the whole system can be obtained.In the light of the conflict of water drainage,water supply and eco-environment protection in a typical sector in Jiaozuo coal mine,a case study puts forward an optimum combination scheme,in which a maximum economic benefit objective is constrained by multiple factors.The scheme provides a very important scientific base for finding a sustainable development strategy.Keywords combination system of water drainage,water supply and eco-environment protection,optimal combination,resourcification of mine water.1Analyses of necessity for the combinationThere are three related problems in the basin.It is well known that the major mine-hydrogeological characteristics of the coal accumulated basin in North China display a stereo water-filling structure,which is formed by multi-layer aquifers connected hydraulically together with various kinds of inner or outer boundaries.Mine water hazards have seriously restricted the healthy development of coal industry in China because of more water-filling sources and stronger water-filling capacity in coal mines of the basin.Coal reserves in the basin are threatened by the water hazards.In Fengfeng,Xingtai,Jiaozuo,Zibao,Huaibei and Huainan coal mine districts,for example,it is estimatedthat coal reserves are threatened by the water hazards up to 52％,71.％40,％,60％,48％and 90％of total prospecting reserves respectively.It is obvious that un-mining phenomenon caused by the water hazards is serious.Water-bursting accidents under coal layers have seriously influenced safe production.Some statistical data show that there were 17 water-bursting accidents with over 1 m3/s inflow from 1985.Water drainage is an increasing burden on coal mines threatened by water hazards:high cost of water drainage raises coal prices and reduces profits of the enterprise.On the other hand,it is more and more difficult to meet the demand of water supply in coal mine districts in the basin.The reasons are not only arid and semi-arid weather conditions,but also a large amount of water drainage with deep drawdown in coal mines and irrational water exploitation.The deterioration of eco-environment is another problem.Phenomena of land surface karst collapse can be found.Many famous karst springs,which are discharge points for the whole karst groundwater syatem,stop flowing or their discharge rates decrease on a large scale.Desert cremophytes in large areas in west China die because of falling groundwater level.These three problems are related and contradictory.In order to solve the problems while ensuring safe mining,meeting water resource demands and slowing down the pace of eco-environment deterioration,it is necessary to study the optimum combination of water drainage,water supply and eco-environment protection in the basin.2The state of the art of research and the problemsAlthough research into the combination of water drainage and water supply started much earlier in some countries,their conception is simple and some shortcomings remain in their study on the theory and pattern of combination.China’s research history on the combination can be divided into three stages.The first stage is the utilization of mine water.A century ago mine water started to be used as water supply for mines.But the utilization scale and efficiency were quite limited at that time.The second stage is a comprehensive one:mine water was used while water hazards were harnessed.Great progress was made both in theory and practice of the combination.For example,the combination of water drainage and water supply not only means the utilization of mine water,but also means that it is a technique of preventing water hazards.It is unfortunate,however,that the combination research in this stage offered less sense ofeco-environment protection.Optimum combination management of water drainage,water supply and eco-environment protection is the third stage.Main features in this stage are to widen traditional research,and to establish an economic-hydraulic management model,in which safe mining,eco-environment protection and sustainable development demands,etc.are simultaneously considered as constraint conditions.3Trinity systemThe trinity system combines water drainage,water supply and eco-environment quality protection.The water-collecting structures of the system consist of land surface pumping wells in the mines,shallow land surface well in groundwater recharge areas and artificial relief wells under the mines.Both integration and coordination for the trinity system are distinguished according to the combination.The integration for the system means to utilize drainage water under the mines and pump water onto the land surface as water supply for different purposes without harming the eco-environmental quality.The coal mines are not only drainage sites,but also water supply sources.The purpose of drilling pumping wells on the land surface is to eliminate special influences on different consumers,which are caused by terminating drainage processes under the mines due to unexpected accidents in mining.The coordination for the system means to bulid some water supply sources for different consumers while ensuring eco-environmental quality in groundwater recharge positions,where pumping groundwater is quite effective on lowering groundwater heads in the mine areas.Itintercepts in advance the recharging groundwater flow towards the mines,which may not only provide consumers with good quality groundwater,achieve the goal of dropping down groundwater heads in the mines,but also effectively reduce the high costs of drainage and water treatment,which are needed by traditional dewatering measures with large drainage flow rates under the mines.The coordination changes the traditional passive pattern of preventing and controlling groundwater hazards under the mines into that of active surface interception.Both very developed karst flow belts and accumulated groundwater recharge ones under the ground are relatively ideal interceptive coordination positions in the system.For the integration of the trinity system,artificial relief wells under the mines and the land surface pumping wells mainly penetrate into direct thin bedded karst aquifers interbedded with the mining coal layers,while for the coordination of the system,the shallow land surface wells mainly penetrate into very thick karst aquifer.Therefore,hydrogeological conceptual model for the system involves the multi-layer aquifers connected hydraulically by different inner boundaries.Setting up stereo hydrogeological conceptual models and corresponding mathematical models is a prerequisite for solving the managemental problems for the system.Management of the trinity system not only considers the effects of lowering groundwater heads and safe operation for water drainage subsystem,but also pays attention to the water demands for water supply subsystem and quality changes for eco-environment protection subsystem.They play the same important role in the whole combination system.It controls the groundwater heads in each aquifer to satisfy the conditions of safe mining with certain water head pressures in the mines,and to guarantee a certain amount of water supply for the mines and near areas,but the maximum drawdown of groundwater must not be ex ceded,which may result in lowering eco-environmental quality.4Economic-hydraulic management modelIn the trinity system management,groundwater resources in the mines and nearby areas,which are assessed on the premise of eco-environment qualities and safe operation in the mines,may be provided as water supply prices,drainage costs,transportation costs(including pipeline and purchasing the land costs)and groundwater quality treatment costs for the three different waterconsumers,the optimum management models may automatically allocate to each consumer a certain amount of groundwater resources and a concrete water supply scenario based on comparisons of each consumer’s economic contribution to the whole system in objective function.Therefore the management studies on the optimal combination among water drainage,water supply and eco-environment protection involve both the management of groundwater hydraulic techniques and the economic evaluations,eco-environment quality protection and industrial structure programs.In addition to realizing an economic operation,they also guarantee a safe operation which is a key point for the combination of the whole system.5The management model for the trinity system can reach water supply goals with drainage water under the mines and the land surface pumping water on the premise of ensuring eco-environmental quality.And it can make use of one model to lay down comprehensively optimum management scenarios for each subsystem by means of selecting proper constraints and maximum economic benefit objective produced by multiple water consumers.The model can raise the security and reliability of operation for the whole trinity system,and the drainage water can be forecast for the mines and the management of water supply resource and the evaluation of eco-environment quality can be performed at the same time so as to respectively stop the separate or closed management,of departments of drainage water,water supply and eco-environment protection from geological survey stage to management evaluation.This,in economic aspect,can not only avoid much geological survery and special assessment work which are often repeated by the three departments,and save a lot of funds,but also ,in technical aspect,make use of one model to simultaneously consider interference and influence on each other for different groundwater seepage fields so as to guarantee calculating precision of the forecast,the management and the evaluation work.The economic-hydraulic management model can be expressed as follows.6 A case studyA typical sector is chosen.It is located in the east of Jiaozuo coal mine,Henan Province,China.Itconsists of three mines:Hanwang Mine,Yanmazhuang Mine and Jiulishan Mine.The land surface is flat,and the whole area is about 30 km2.An intermittent river Shanmen flows through the sector from the north to the south.Average annual precipitation in the sector is about 662.3mm.Theprecipitation mainly concentrates inJune,July,August and September each year.Strata in the sector consist of very thick limestone in Middle Ordovician,coal-bearing rock series in Permo Carboniferous and loose deposits in Quaternary.There are four groups of faulted structures.The first is in northeast-southwest direction such as F3 and F1..The second is in the northwest-southeast direction such as Fangzhuang fault.The third is in the east-west direction such as Fenghuangling fault.The last is almost in north-south.These faults are all found to be normal faults with a high degree of dip angle.Four major aquifers have been found in the sector.The top one is a semi-confined porous aquifer.The next one is a very thin bedded limeston aquifer.The third is a thin bedded limestone aquifer.The last one at the bottom is a very thick limestone aquifer.Objective function of the management model is designed to be maximum economic benefit produced by domestic,industrial and agricultural water supply.Policy making variables of the model are considered as the domestic,industrial and agricultural groundwater supply rates in every management time step,and they are supplied by artificial relief flow wells under the mines,the land surface pumping wells in the mines and the shallow land surface wells in the groundwater recharge areas.All the 135 policy making variables are chosen in the model,27 for drainage wells under the mines in aquifer,27 for the land surface pumping wells in the mine districts in aquifer 27 in aquifer 27 in aquifer O2 27 for the shallow land surface wells in aquifer O2Based on the problems,the following constraint conditions should be considered:(1)Safe mining constraint with groundwater pressure in aquifer L8.There are altogether three coalmines in the typical sector,i.e.Hanwang Mine,Yanmazhuang Mine and Jiulishan Mine.Elevations of mining level for these mines are different because it is about 88-150 m in the second mining level for Hanwang Mine,and -200m in the second mining level for Yanmazhuang Mine,and-225 m in the first mining level for Jiulishan Mine.According to mining experiences,pressure-loaded heights for groundwater heads in safe mining state are considered as about 100-130m.Therefore,the groundwater level drawdowns in the three management time steps for aquifer L8 at three mines have to be equivalent to safe drawdown values at least in order to pervert groundwater hazards under the mines and to guarantee their safe operation.(2)Geological eco-environment quality constraint.In order to prevernt groundwater leakage fromupper contaminater porous aquifer into bottom one and then to seepage further down to contaminate the thin bedded limestone aquifer in the position of buried outcrop,the groundwater heads in the bottom porous aquifer must keep a certain height,i.e.the groundwater drawdowns in it are not allowed to exceed maximum values.(3)Groundwater head constraint at the shallow land surface wells in aquifer O2,The shallow landsurface wells should penetrate in aquifer O2 in order to avoid geological environment hazards,such as karst collapse and deep karst groundwater contamination.Groundwater head drawdowns in aquifer O2 for the shallow land surface wells are not allowed to exceed criticalvalues.(4)Industrial water supply constraint for the groundwater source in aquifer O2 .The rate ofindustrial water supply needed by the planned thermal power plant in the north of the sectoris designed to be 1.5 m3/s according to the comprehensive design of the system in thesector.In order to meet the demands of water,the rate industrial water supply for thegroundwater source in aquifer O2 in every management time step must be equivalent at leastto 1.5 m3/s.(5)Maximum amount constraint of groundwater resource available for abstraction.In order tomaintain the balance of the groundwater system in the sector for a long time and to avoid anyharmful results caused by continuous falling of groundwater head,the sum of groundwaterabstraction in each management time step is not allowed to exceed the maximum amount ofgroundwater resource available for abstraction.Since there is not only water drainage in the mines,but also water supply in the whole combination system,management period for the model is selected from June 1,1978 to May 31,1979,in which annual average rate of precipitation is about 50％.Management time steps for the period are divided into three.The first one is from June to September,the second from October to next January,and the last one from next February to May.According to comprehensive information about actual economic ability,economic development program and industrial structure adjustment in the sector at present and in the near future,and different association forms of water collecting structures among the land surface pumping wells,the shallow land surface wells and artificial relief flow wells under the mines,this paper designs 12 management scenarious,all of which take the safe operation in the trinity system as the most important condition.After making comparisons of optimum calculation results for the 12 scenarious,this paper comes to a conclusion that scenarios is the most ideal and applicable one for the typical sector.This scenario not only considers the effective dewatering advantage of the artificial relief flow wells under the mines and safe stable water supply advantage of the land surface pumping wells,but also pays attention to the disadvantage of low safe guaranty rate for the relief flow wells under the mines for water supply and of large drilling investment in the land surface pumping wells.Meanwhile,eh shallow land surface wells inaquifer O2in this scenario would not only provide water supply for the thermal power plant as planned,but also play an important role in dewatering the bottom aquifer,which is major recharge source of groundwater for the mines.If the drainage subsystem under the mines runs normally,this scenario could fully offer the effective dewatering functions of the artificial relief flow wells under the mines,and makes the trinity system operate normally.But if the drainage subsystem has to stop suddenly because of unexpected accidents,the scenario could still fully utilize the land surface pumping wells and the shallow land surface wells,and increae their pumping rates in order to make up for temporary shortage of water supply for the trinity system and to make its economic losses reduced to a minimum extent.Increasing groundwater abstraction rate for the land surface pumping wells and the shallow land surface wells,in fact,is very favorable for harnessing the water-accidents under the mines and for recovery production of the mines.To sum up,this scenario sets up a new pattern for the combination of water drainage,water supply and eco-environment protection.It solves quite well the conflicts between the low safe guaranty rate and the effective dewatering result for the artificial relief flow wells under the mines.It makes full use of beneficial aspect of the conflicts,and meanwhile compensates for the unbeneficial one by arranging the land surface pumping wells in the coal mine districts.Therefore,this scenario should be comprehensive and feasible.In this scenario,Hanwan Mine,Yanmazhuang Mine and Jiulishan Mine are distributed optimally for certain amount of domestic and industrial water supply,but not for much agricultural water supply.The land surface pumping wells are also distributed for different purposes of water supply.The water supply for the thermal power plant (1.5 m3/s) is provided by the shallow land surface prehensive effects,produced by the above three kinds of water collecting structures,completely satisfy all of the constraint conditions in the management model,and achieve an extremely good economic objective of 16.520551million RMB yuan per year.In order to examine the uncertainty of the management model,12management scenarios are all tested with sensitive analysis.7Conclusion(1)The optimum combination research among water drainage,water supply and eco-environmentprotection is of great theoretical significance and application value in the basin of North China for solving unbalanced relation between water supply and demands,developing new potential water supply sources and protecting weak eco-environment.(2)The combination research is concerned not only with hydraulic technique management but alsowith constraints of economic benefits,society,ecology,environment quality,safe mining and sustainable development in the coal mines.(3)The combination model,for the first time,breaks up the closed situation existing for a longtime,under which the government departments of drainage water,water supply and eco-environment protection from geological survey stage to management evaluation work respectively.Economically,it can spare the repeated geological survey and special assessment work done by the three departments and save a lot of funds;technically,one model is made use of to cover the interference and influence each other for different groundwater seepage fields soas to guarantee a high calculating precision of the forecast,the management and the evaluation work.(4)The management scenario presented in the case study is the most ideal and applicable for thetypical sector.This scenario not only makes full use of the effective dewatering advantages of the artificial relief flow wells under the mines and safe stable water supply advantages of the land surface pumping wells,but also pays attention to the disadvantages of low safe guaranty rate for the relief flow wells under the mines for water supply and of large drilling investment for the land surface pumping wells.References1.Investigation team on mine-hydrogeology and engineering geology in the Ministry ofGeology and Mineral Resources.Investigation Report on Karst-water-filling Mines(inChinese).Beijing:Geological Publishing House,19962.Liu Qiren,Lin Pengqi,Y u Pei,Investigation comments on mine-hydrogeological conditionsfor national karst-water-filling mines,Journal of Hydrogeology and Engineering Geology(in Chinese),19793.Wang Mengyu,Technology development on preventing and curing mine water in coalmines in foreign countries,Science and Technology in Coal(in Chinese),19834.Coldewey,W.G.Semrau.L.Mine water in the Ruhr Area(Federal Republic of Germany),inProceedings of 5th International Mine Water Congress,Leicestershire:Quorn SelectiveRepro Limited,19945.Sivakumar,M.Morten,S,Singh,RN,Case history analysis of mine water pollution,inProceedings of 5th International Mine Water Congress,Leicestershire;Quorn SelectiveRepro Limited,19946.Ye Guijun.Zhang Dao,Features of Karst-water-filling mines and combination betweenwater drainage and water supply in China,Journal of Hydrogeology and EngineeringGeology(in China),19887.Tan Jiwen,Shao Aijun,Prospect analyses on Combination between water drainage andwater supply in karst water basin in northern China,Jounnal of Hebei College ofGeology(in Chinese),19858.Xin Kuide,Yu Pei,Combination between water drainage and water for seriouskarst-water-filling mines in northern China,Journal of Hydrogeology and Engineering Geology(in Chinese),19869.Wu Qiang,Luo Yuanhua,Sun Weijiang et al.Resourcification of mine water andenvironment protection,Geological Comments(in Chinese),199710.Gao Honglian,Lin Zhengping,Regional characteristics of mine-hydrogeological conditionsof coal deposits in China,Journal of Hydrogeology and Engineering Geology(in Chinese),198511.Jiang Ben,A tentative plan for preventing and curing measures on mine water in coal minesin northern China,Geology and Prospecting for Coaofield(in Chinese),1993中国北方煤炭积聚区的最佳组合排水，供水和生态环境保护摘要为了开采中国北方煤炭资源丰富的区域，不合理的排水使排水、供水和保护生态环境之间的冲突日趋严重。
关于给排水的专业作文英语
As a high school student with a keen interest in the field of civil engineering, Ive always been fascinated by the intricate systems that make our cities function smoothly. One such system is the one that deals with the supply and removal of water the drainage and water supply systems. This essay aims to delve into the importance of these systems, their components, and the role they play in our daily lives.Growing up in a city, I often took for granted the water that comes out of the tap or the way waste disappears down the drain. It wasnt until I started researching the field of sanitary engineering that I realized the complexity and the marvel of the systems that make these things possible. The water supply system is the lifeline of any city, ensuring that every household and business has access to clean, potable water.The process begins with the collection of water from various sources such as rivers, lakes, or underground aquifers. This raw water undergoes a series of treatments to remove impurities and contaminants. Filtration, disinfection, and sometimes even desalination are part of the purification process that turns raw water into the clean water we use for drinking, cooking, and cleaning.Once treated, the water is stored in reservoirs and then distributed through an extensive network of pipes. This distribution system is a marvel of engineering, designed to withstand pressure and ensure that water reaches every corner of the city. The design of these systems must take into account factors such as population density, water demand, and the geography of the area.On the flip side, the drainage system is equally crucial. It is responsible for the removal of wastewater from homes and industries. This includes everything from the water we use for washing dishes to the water that flows down the drain in our bathrooms. The wastewater is collected through a network of sewers and transported to treatment plants.Here, the wastewater undergoes a process of treatment to remove harmful substances and pollutants. This is a critical step in preventing the contamination of our water bodies and ensuring the health of our ecosystems. The treated water is then either released back into the environment or reused for nonpotable purposes such as irrigation or industrial use.The design and maintenance of these systems require a deep understanding of hydrology, environmental science, and engineering principles. Its not just about ensuring the availability of water its also about managing water resources sustainably. This involves considerations of water conservation, energy efficiency, and the impact of these systems on the environment.In recent years, there has been a growing focus on the integration of smart technologies into these systems. Sensors, data analytics, and automation are being used to improve the efficiency and reliability of water supply and drainage systems. For instance, realtime monitoring of water quality can help detect and address issues before they become major problems.Moreover, the concept of green infrastructure is gaining traction. This involves the use of natural processes and systems to manage water. Rain gardens, permeable pavements, and constructed wetlands are examples of green infrastructure that can help reduce the load on conventional drainage systems and improve water quality.In conclusion, the water supply and drainage systems are the unsung heroes of our urban environments. They play a critical role in ensuring the health, comfort, and sustainability of our cities. As a future civil engineer, I am excited about the prospect of contributing to the development and improvement of these systems. Whether its through innovative design, the integration of smart technologies, or the adoption of green infrastructure, there is so much potential to make these systems more efficient, sustainable, and resilient.。
建筑工程及给排水专业中英文对照翻译
建筑工程及给排水专业中英文对照翻译Laminar and Turbulent FlowObservation shows that two entirely different types of fluid flow exist. This was demon- strated by Osborne Reynolds in 1883 through an experiment in which water was discharged from a tank through a glass tube. The rate of flow could be controlled by a valve at the outlet, and a fine filament of dye injected at the entrance to the tube. At low velocities, it was found that the dye filament remained intact throughout the length of the tube, showing that the particles of water moved in parallel lines. This type of flow is known as laminar, viscous or streamline, the particles of fluid moving in an orderly manner and retaining the same relative positions in successive cross- sections.As the velocity in the tube was increased by opening the outlet valve, a point was eventually reached at which the dye filament at first began to oscillate and then broke up so that the colour was diffused over the whole cross-section, showing that the particles of fluid no longer moved in an orderly manner but occupied different relative position in successive cross-sections. This type of flow is known as turbulent and is characterized by continuous small fluctuations in the magnitude and direction of the velocity of the fluid particles, which are accompanied by corresponding small fluctuations of pressure.When the motion of a fluid particle in a stream is disturbed, its inertiawill tend to carry it on in the new direction, but the viscous forces due to the surrounding fluid will tend to make it conform to the motion of the rest of the stream. In viscous flow, the viscous shear stresses are sufficient to eliminate the effects of anydeviation, but in turbulent flow they are inadequate. The criterion which determines whether flow will be viscous of turbulent is therefore the ratio of the inertial force to the viscous force acting on the particle. The ratioμρvl const force Viscous force Inertial ?= Thus, the criter ion which determines whether flow is viscous or turbulent is the quantity ρvl /μ, known as the Reynolds number. It is a ratio of forces and, therefore, a pure number and may also be written as ul /v where is the kinematic viscosity (v=μ/ρ).Experiments carried out with a number of different fluids in straight pipes of different diameters have established that if the Reynolds number is calculated by making 1 equal to the pipe diameter and using the mean velocity v , then, below a critical value of ρvd /μ = 2000, flow will normally be laminar (viscous), any tendency to turbulence being damped out by viscous friction. This value of the Reynolds number applies only to flow in pipes, but critical values of the Reynolds number can be established for other types of flow, choosing a suitable characteristic length such as the chord of an aerofoil in place of the pipe diameter. For a given fluid flowing in a pipe of a given diameter, there will be a critical velocity of flow corresponding to the critical value of the Reynolds number, below which flow will be viscous.In pipes, at values of the Reynolds number > 2000, flow will not necessarily be turbulent. Laminar flow has been maintained up to Re = 50,000, but conditions are unstable and any disturbance will cause reversion to normal turbulent flow. In straight pipes of constant diameter, flow can be assumed to be turbulent if the Reynolds number exceeds 4000.Pipe NetworksAn extension of compound pipes in parallel is a case frequently encountered in municipal distribution system, in which the pipes are interconnected so that the flow to a given outlet may come by several different paths. Indeed, it is frequently impossible to tell by inspection which way the flow travels. Nevertheless, the flow in any networks, however complicated, must satisfy the basic relations of continuity and energy as follows:1. The flow into any junction must equal the flow out of it.2. The flow in each pipe must satisfy the pipe-friction laws for flow in a single pipe.3. The algebraic sum of the head losses around any closed circuit must be zero.Pipe networks are generally too complicated to solve analytically, as was possible in the simpler cases of parallel pipes.A practical procedure is the method of successive approximations, introduced by Cross. It consists of the following elements, in order:1. By careful inspection assume the most reasonable distribution of flows that satisfies condition 1.2. Write condition 2 for each pipe in the formh L = KQ n(7.5) where K is a constant for each pipe. For example, the standard pipe-friction equation would yield K= 1/C2and n= 2 for constant f. Minor losses within any circuit may be included, but minor losses at the junction points are neglected.3. To investigate condition 3, compute the algebraic sum of the head losses around each elementary circuit. ∑h L= ∑KQ n. Consider losses from clockwise flows as positive, counterclockwise negative. Only by good luck will these add tozero on the first trial.4. Adjust the flow in each circuit by a correction, ΔQ , to balance the head in that circuit and give ∑KQ n = 0. The heart of this method lies in the determination of ΔQ . For any pipe we may writeQ = Q 0 ＋ΔQwhere Q is the correct discharge and Q 0 is the assumed discharge. Then, for a circuit100/Q h n h Q Kn Q K Q L L n n ∑∑∑∑?-=-=- (7.6) It must be emphasized again that the numerator of Eq. (7.6) is to be summed algebraically, with due account of sign, while the denominator is summed arithmetically. The negative sign in Eq.(7.6) indicates that when there is an excess of head loss around a loop in the clockwise direction, the ΔQ must be subtracted from clockwise Q 0’s and added to counterclockwise ones. The reverse is true if there is a deficiency of head loss around a loop in the clockwise direction.5. After each circuit is given a first correction, the losses will still not balance because of the interaction of one circuit upon another (pipes which are common to two circuits receive two independent corrections, one for each circuit). The procedure is repeated, arriving at a second correction, and so on, until the corrections become negligible.Either form of Eq. (7.6) may be used to find ΔQ . As values of K appear in both numerator and denominator of the first form, values proportional to the actual K may be used to find the distribution. Thesecond form will be found most convenient for use with pipe-friction diagrams for water pipes.An attractive feature of the approximation method is thaterrors in computation have the same effect as errors in judgment and will eventually be corrected by the process.The pipe-networks problem lends itself well to solution by use of a digital computer. Programming takes time and care, but once set up, there is great flexibility and many man-hours of labor can be saved.The Future of Plastic Pipe at Higher PressuresParticipants in an AGA meeting panel on plastic pipe discussed the possibility of using polyethylene gas pipe at higher pressures. Topics included the design equation, including work being done by ISO on an updated version, and the evaluation of rapid crack propagation in a PE pipe resin. This is of critical importance because as pipe is used at higher pressure and in larger diameters, the possibility of RCP increases.Se veral years ago, AGA’s Plastic Pipe Design Equation Task Group reviewed the design equation to determine if higher operating pressurescould be used in plastic piping systems. Members felt the performance of our pipe resins was not truly reflected by the design equation. It was generally accepted that the long-term properties of modern resins far surpassed those of older resins. Major considerations were new equations being developed and selection of an appropriate design factor.Improved pipe performanceMany utilities monitored the performance of plastic pipe resins. Here are some of the long-term tests used and the kinds of performance change they have shown for typical gas pipe resins.Elevated temperature burst testThey used tests like the Elevated Temperature Burst T est, inwhich the long-term performance of the pipe is checked by measuring the time required for formation of brittle cracks in the pipe wall under high temperatures and pressures (often 80 degrees C and around 4 to 5-MPa hoop stress). At Consumers Gas we expected early resins to last at least 170 hrs. at 80 degrees C and a hoop stress of 3 MPa. Extrapolation showed that resins passing these limits should have a life expectancy of more than 50 yrs. Quality control testing on shipments of pipe made fromthese resins sometimes resulted in product rejection for failure to meet this criterion.At the same temperature, today’s resins last thousands of hours at hoop stresses of 4.6 MPa. Tests performed on pipe made from new resins have been terminated with no failure at times exceeding 5,700 hrs. These results were performed on samples that were squeezed off before testing. Such stresses were never applied in early testing. When extrapolated to operating conditions, this difference in test performance is equivalent to an increase in lifetime of hundreds (and in some cases even thousands) of years.Environmental stress crack resistance testSome companies also used the Environmental Stress Crack Resistance test which measured brittle crack formation in pipes but which used stress cracking agents to shorten test times.This test has also shown dramatic improvement in resistance brittle failure. For example, at my company a test time of more than 20 hrs. at 50 degrees C was required on our early resins. Today’s resins last well above 1,000 hrs. with no failure.Notch testsNotch tests, which are quickly run, measure brittle crack formation in notched pipe or molded coupon samples. This isimportant for the newer resins since some other tests to failure can take very long times. Notch test results show that while early resins lasted for test times ranging between 1,000 to 10,000 min., current resins usually last for longer than 200,000 min.All of our tests demonstrated the same thing. Newer resins are much more resistant to the growth of brittle crack than their predecessors. Since brittle failure is considered to be the ultimate failure mechanism in polyethylene pipes, we know that new materials will last much longer than the old. This is especially reassuring to the gas industry since many of these older resins have performed very well in the field for the past 25 yrs. with minimal detectable change in properties.While the tests showed greatly improved performance, the equation used to establish the pressure rating of the pipe is still identical to the original except for a change in 1978 to a single design factor for all class locations.To many it seemed that the methods used to pressure rate our pipe were now unduly conservative and that a new design equation was needed. At this time we became aware of a new equation being balloted atISO. The methodology being used seemed to be a more technically correct method of analyzing the data and offered a number of advantages.Thermal Expansion of Piping and Its CompensationA very relevant consideration requiring careful attention is the fact that with temperature of a length of pipe raised or lowered, there is a corresponding increase or decrease in its length and cross-sectional area because of the inherent coefficient of thermal expansion for the particular pipe material. The coefficient of expansion for carbon steel is 0.012 mm/m?Cand for copper 0.0168mm/m?C. Respective module of elasticity a re for steel E = 207×1.06kN/m2 and for copper E = 103×106 kN/m2. As an example, assuming a base temperature for water conducting piping at 0?C, a steel pipe of any diameter if heated to 120?C would experience a linear extension of 1.4 mm and a similarly if heated to copper pipe would extend by 2.016 mm for each meter of their respective lengths. The unit axial force in the steel pipe however would be 39% greater than for copper. The change in pipe diameter is of no practical consequence to linear extension but the axial forces created by expansion or contractionare con- siderable and capable of fracturing any fitments which may tend to impose a restraint;the magnitude of such forces is related to pipe size. As an example,in straight pipes of same length but different diameters, rigidly held at both ends and with temperature raised by say 100?C, total magnitude of linear forces against fixed points would be near enough proportionate to the respective diameters.It is therefore essential that design of any piping layout makes adequate com- pensatory provision for such thermal influence by relieving the system of linear stresses which would be directly related to length of pipework between fixed points and the range of operational temperatures.Compensation for forces due to thermal expansion. The ideal pipework as far as expansion is concerned, is one where maximum free movement with the minimum of restraint is possible. Hence the simplest and most economical way to ensure com- pensation and relief of forces is to take advantage of changes in direction, or where this is not part of the layout and long straight runs are involved it may be feasible to introducedeliberate dog-leg offset changes in direction at suitable intervals.As an alternative,at calculated intervals in a straight pipe run specially designed expansion loops or “U” bends should be inserted. Depending upon design and space availability, expansion bends within a straight pipe run can feature the so called double offset “U” band or thehorseshoe typ e or “lyre” loop.The last named are seldom used for large heating networks; they can be supplied in manufacturers’ standard units but require elaborate constructional works for underground installation.Anchored thermal movement in underground piping would normally be absorbed by three basic types of expansion bends and these include the “U”bend, the “L”bend and the “Z”bend.In cases of 90 changes indirection the “L” and “Z”bends are used.Principles involved in the design of provision for expansion between anchor points are virtually the same for all three types of compensator. The offset “U” bend is usually made up from four 90° elbows and straight pipes; it permits good thermal displacement and imposes smaller anchor loads than the other type of loop. This shape of expansion bend is the standardised pattern for prefabricated pipe-in-pipe systems.All thermal compensators are installed to accommodate an equal amount of expansion or contraction; therefore to obtain full advantage of the length of thermal movement it is necessary to extend the unit during installation thus opening up the loop by an extent roughly equal the half the overall calculated thermal movement.This is done by “cold-pull” or other mechanical means. The total amount of extension between two fixed pointshas to be calculated on basis of ambient temperature prevailing and operational design temperatures so that distribution of stresses and reactions at lower and higher temperatures are controlledwithin permissible limits. Pre-stressing does not affect the fatigue life of piping therefore it does not feature in calculation of pipework stresses .There are numerous specialist publication dealing with design and stressing calculations for piping and especially for proprietary piping and expansion units; comprehensive experience back design data as well as charts and graphs may be obtained in manufacturers’publications, offering solutions for every kind of pipe stressing problem.As an alternative to above mentioned methods of compensation for thermal expansion and useable in places where space is restricted, is the more expensive bellows or telescopic type mechanical compensator. There are many proprietary types and models on the market and the following types of compensators are generally used.The bellows type expansion unit in form of an axial compensator provides for expansion movement in a pipe along its axis; motion in this bellows is due to tension or compression only.There are also articulated bellows units restrained which combine angular and lateral movement; they consist of double compensator units restrained by straps pinned over the center of each bellowsor double tied thus being restrained over its length.Such compensators are suitable for accommodating very pipeline expansion and also for combinations of angular and lateral movements.层流与紊流有两种完全不同的流体流动形式存在，这一点在1883年就由Osborne Reynolds 用试验演示证明。
给水排水专业外语论文
The activated-sludge processAbstract--This paper introduces the composition and principle of activated-sludge process,recent developments and future developments tendency.It also provides a design scheme and a example.Key words--activated-sludge,aeration tank,computer simulation,design scheme1.IntroductionThe activated-sludge process is a biological method of wastewater treatment that is performed by a variable and mixed community of microorganisms in an aerobic aquatic environment. These microorganisms derive energy from carbonaceous organic matter in aerated wastewater for the production of new cells in a process known as synthesis, while simultaneously releasing energy through the conversion of this organic matter into compounds that contain lower energy, such as carbon dioxide and water, in a process called respiration. As well, a variable number of microorganisms in the system obtain energy by converting ammonia nitrogen to nitrate nitrogen in a process termed nitrification. This consortium of microorganisms, the biological component of the process, is known collectively as activated sludge.The overall goal of the activated-sludge process is to remove substances that have a demand for oxygen from the system. This is accomplished by the metabolic reactions (synthesis-respiration and nitrificaction) of the microorganisms, the separation and settling of activated-sludge solids to create an acceptable quality of secondary wastewater effluent, and the collection and recycling of microorganisms back into the system or removal of excess microorganisms from the system.2.The principle of the activated-sludge process2.1The components of the activated-sludge processBefore beginning a discussion of the biological component of the system, an overview of the physical components that comprise the activated-sludge process would seem to be in order. This will help the reader gain a better understanding of the environment in which a mixed community of microorganisms metabolizes organic matter, settles to form a thickened sludge, and is recycled back into or removed from the system.According to Activated Sludge, Manual of Practice(Water Environment Association, 1987),the activated-sludge process contains five essential interrelated equipment components. The first is an aeration tank or tanks in which air or oxygen is introduced into the system to create an aerobic environment that meets the needs of the biological community and that keeps the activated sludge properly mixed. At least seven modifications in the shape and number of tanks exist to produce variations in the pattern of flow.Second, an aeration source is required to ensure that adequate oxygen is fed into the tank(s) and that the appropriate mixing takes place. This source may be provided by pure oxygen, compressed air or mechanical aeration. Just as there are modifications in the shape and number of aeration tanks that can be used in the activated-sludge process, different equipment systems exist to deliver air or oxygen into aeration tanks.Third, in the activated-sludge process, aeration tanks are followed by secondary clarifiers. In secondary clarifiers, activated-sludge solids separate from the surrounding waterwater by the process of flocculation (the formation of large particle aggregates, or flocs, by the adherence of floc-formingorganisms to filamentous organisms) and gravity sedimentation, in which flocs settle toward the bottom of the clarifier in a quiescent environment. This separation leads ideally to the formation of a secondary effluent (wastewater having a low level of activated-sludge solids in suspension) in the upper portion of the clarifier and a thickened sludge comprised of flocs, termed return activated sludge, or RAS, in the bottom portion of the clarifier. Next, return activated sludge must be collected from the secondary clarifiers and pumped back to the aeration tank(s) before dissolved oxygen is depleted. In this way, the biological community needed to metabolize influent organic or inorganic matter in the wastewater stream is replenished.Finally, activated sludge containing an overabundance of microorganisms must be removed, or wasted (waste activated sludge, or WAS), from the system. This is accomplished with the use of pumps and is done in part to control the food-to-microorganism ratio in the aeration tank(s).2.2The basic process of the activated-sludge processThe process involves air or oxygen being introduced into a mixture of primary treated or screened sewage or industrial wastewater (called wastewater from now on) combined with organisms to develop a biological floc which reduces the organic content of the sewage. This material, which in healthy sludge is a brown floc, is largely composed of saprotrophic bacteria but also has an important protozoan flora mainly composed of amoebae,Spirotrichs,Peritrichs including Vorticellids and a range of other filter feeding species. Other important constituents include motile and sedentary Rotifers. In poorly managed activated sludge, a range of mucilaginous filamentous bacteria can develop including Sphaerotilus natans which produces a sludge that is difficult to settle and can result in the sludge blanket decanting over the weirs in the settlement tank to severely contaminate the final effluent quality. This material is often described as sewage fungus but true fungal communities are relatively uncommon.The combination of wastewater and biological mass is commonly known as mixed liquor. In all activated sludge plants, once the wastewater has received sufficient treatment, excess mixed liquor is discharged into settling tanks and the treated supernatant is run off to undergo further treatment before discharge. Part of the settled material, the sludge, is returned to the head of the aeration system to re-seed the new wastewater entering the tank. This fraction of the floc is called return activated sludge (R.A.S.). Excess sludge is called surplus activated sludge(S.A.S.) or waste activated sludge(W.A.S). S.A.S is removed from the treatment process to keep the ratio of biomass to food supplied in the wastewater in balance. S.A.S is stored in sludge tanks and is further treated by digestion, either under anaerobic or aerobic conditions prior to disposal.Many sewage treatment plants use axial flow pumps to transfer nitrified mixed liquor from the aeration zone to the anoxic zone for denitrification. These pumps are often referred to as internal mixed liquor recycle pumps (IMLR pumps). The raw sewage, the RAS, and the nitrified mixed liquor are mixed by submersible mixers in the anoxic zones in order to achieve denitrification.Activated sludge is also the name given to the active biological material produced by activated sludge plants.4.Developments of activated-sludge process4.1Recent developments of activated-sludge processAn innovative activated sludge system without excess sludge production was introduced to thethree existing treatment plants receiving of petrochemical wastewater totally about 17.5ton CODcr/day and 9,600 m3/day in Japan. In the system, simultaneous sludge treatment and wastewater treatment is possible in the same aeration tank. A part of sludge returning from the secondary settling tank is ozonated to change it to more biodegradable compounds and the ozonated sludge is then put into the aeration tank for biological degradation. The degree of excess sludge reduction is controlled by the changing sludge mass to be ozonated. The kinetics and stoichiometrics of ozonated sludge were incorporated into Activated Sludge Model No.1 (ASM1) to predict MLSS concentration and oxygen uptake rate in the each aeration tank. The prediction by the process & hydraulic models matched very reasonably in the dynamic conditions with the changing influent loading rate and the ozonation. The system has been demonstrated successfully by minimal excess sludge withdrawing for more than four years. The water qualities in the effluent also kept at acceptable levels and below the local regulation.4.2Future developments of activated-sludge processTill now,numerous modifications of activated-sludge process have evolved in the last 10 to 20 years.Many new technologies appear,such as MBR,computer modeling.Nearly all of the various modifications are based on the same fundamental principles of biological treatment.Because the design and operation of the activated-sludge process is becoming more complex,a mathematical model of the activated-sludge process has been derived which considers the fate of bacteria which flocculate, bacteria which do not flocculate, and two forms of ciliated protozoa. Computer simulation techniques have been used to study the population dynamics of these organisms in a single completely-mixed and a series of completely-mixed activated-sludge reactor systems; in both cases steady-state solutions were obtained. At steady state, the concentration of soluble substrate in the effluent is determined by the growth rate (fixed by the sludge-wastage rate) of the sludge bacteria. The concentration of dispersed bacteria in the effluent is similarly determined by the growth rate of the ciliated protozoa. The model predicts that the habit of ciliated protozoa would have a considerable effect on effluent quality. A plant containing only free-swimming ciliates would produce a fairly turbid effluent whereas a plant containing attached ciliates would produce a highly clarified effluent. Activated-sludge plants which contain no protozoa would be expected to deliver very turbid effluents although the concentration of soluble substrates would be precisely the same in all three cases. It was possible to simulate successions of organisms which are qualitatively similar to those observed in practice when an activated-sludge plant is set into operation. The results of the model predictions are discussed in the light of full-scale and experimental-scale observations.5.Design of Activated-sludgedesign scheme5.1Activated Sludge Process VariablesThe main variables of activated sludge process are the mixing regime, loading rate, and the flow scheme.5.2Mixing RegimeGenerally two types of mixing regimes are of major interest in activated sludge process: plug flow and complete mixing. In the first one, the regime is characterized by orderly flow of mixed liquor through the aeration tank with no element of mixed liquor overtaking or mixing with any other element. There may be lateral mixing of mixed liquor but there must be no mixing along the path of flow.In complete mixing, the contents of aeration tank are well stirred and uniform throughout. Thus, at steady state, the effluent from the aeration tank has the same composition as the aeration tank contents.The type of mixing regime is very important as it affects (1) oxygen transfer requirements in the aeration tank, (2) susceptibility of biomass to shock loads, (3) local environmental conditions in the aeration tank, and (4) the kinetics governing the treatment process.5.3Loading RateA loading parameter that has been developed over the years is the hydraulic retention time (HRT), q, dq = VQV= volume of aeration tank, m3, and Q= sewage inflow, m3/d5.4Flow Scheme●The flow scheme involves:●the pattern of sewage addition●the pattern of sludge return to the aeration tank and●the pattern of aeration.Sewage addition may be at a single point at the inlet end or it may be at several points along the aeration tank. The sludge return may be directly from the settling tank to the aeration tank or through a sludge reaeration tank. Aeration may be at a uniform rate or it may be varied from the head of the aeration tank to its end.5.6Design ConsiderationThe items for consideration in the design of activated sludge plant are aeration tank capacity and dimensions, aeration facilities, secondary sludge settling and recycle and excess sludge wasting.5.7Aeration TankThe volume of aeration tank is calculated for the selected value ofq c by assuming a suitable value of MLSS concentration, X.VX = YQq c(S O - S)1+ k d q cAlternately, the tank capacity may be designed fromF/M = QS O / XVHence, the first step in designing is to choose a suitable value ofq c(or F/M) which depends on the expected winter temperature of mixed liquor, the type of reactor, expected settlingcharacteristics of the sludge and the nitrification required. The choice generally lies between 5 days in warmer climates to 10 days in temperate ones where nitrification is desired alongwith good BOD removal, and complete mixing systems are employed.The second step is to select two interrelated parameters HRT, t and MLSS concentration. It is seen that economy in reactor volume can be achieved by assuming a large value of X. However, it is seldom taken to be more than 5000 g/m3. For typical domestic sewage, the MLSS value of 2000-3000 mg/l if conventional plug flow type aeration system is provided, or 3000-5000 mg/l for completely mixed types. Considerations which govern the upper limit are: initial and running cost of sludge recirculation system to maintain a high value of MLSS, limitations of oxygen transfer equipment to supply oxygen at required rate in small reactor volume, increased solids loading on secondary clarifier which may necessitate a larger surface area, design criteria for the tank and minimum HRT for the aeration tank.The length of the tank depends upon the type of activated sludge plant. Except in the case of extended aeration plants and completely mixed plants, the aeration tanks are designed as long narrow channels. The width and depth of the aeration tank depends on the type of aeration equipment employed. The depth control the aeration efficiency and usually ranges from 3 to 4.5 m. The width controls the mixing and is usually kept between 5 to 10 m. Width-depth ratio should be adjusted to be between 1.2 to 2.2. The length should not be less than 30 or not ordinarily longer than 100 m.5.8Oxygen RequirementsOxygen is reqiured in the activated sludge process for the oxidation of a part of the influent organic matter and also for the endogenous respiration of the micro-organisms in the system. The total oxygen requirement of the process may be formulated as follows:O2 required (g/d) = Q(S O - S) - 1.42 Q w X rfwhere, f = ratio of BOD5 to ultimate BOD and 1.42 = oxygen demand of biomass (g/g)The formula does not allow for nitrification but allows only for carbonaceous BOD removal.5.9Aeration FacilitiesThe aeration facilities of the activated sludge plant are designed to provide the calculated oxygen demand of the wastewater against a specific level of dissolved oxygen in the wastewater.5.10Sludge RecycleThe MLSS concentration in the aeration tank is controlled by the sludge recirculation rate and the sludge settleability and thickening in the secondary sedimentation tank.Q r = XQ X r-Xwhere Q r = Sludge recirculation rate, m3/dThe sludge settleability is determined by sludge volume index (SVI) defined as volume occupied in mL by one gram of solids in the mixed liquor after settling for 30 min. If it is assumed that sedimentation of suspended solids in the laboratory is similar to that in sedimentation tank, then X r = 106/SVI. Values of SVI between 100 and 150 ml/g indicate good settling of suspended solids. The X r value may not be taken more than 10,000 g/m3unless separate thickeners are provided toconcentrate the settled solids or secondary sedimentation tank is designed to yield a higher value.5.11Excess Sludge WastingThe sludge in the aeration tank has to be wasted to maintain a steady level of MLSS in the system. The excess sludge quantity will increase with increasing F/M and decrease with increasing temperature. Excess sludge may be wasted either from the sludge return line or directly from the aeration tank as mixed liquor. The latter is preferred as the sludge concentration is fairly steady in that case. The excess sludge generated under steady state operation may be estimated byq c = VXQ w X ror Q w X r = YQ (S O - S) - k d XV6.Design exampleDesign of Completely Mixed Activated Sludge SystemDesign a completely mixed activated sludge system to serve 60000 people that will give a final effluent that is nitrified and has 5-day BOD not exceeding 25 mg/l. The following design data is available.Sewage flow = 150 l/person-day = 9000 m3/dayBOD5 = 54 g/person-day = 360 mg/l ; BOD u = 1.47 BOD5Total kjeldahl nitrogen (TKN) = 8 g/person-day = 53 mg/lPhosphorus = 2 g/person-day = 13.3 mg/lWinter temperature in aeration tank = 18°CYield coefficient Y = 0.6 ; Decay constant K d = 0.07 per day ; Specific substrate utilization rate = (0.038 mg/l)-1 (h)-1 at 18°CAssume 30% raw BOD5is removed in primary sedimentation, and BOD5going to aeration is, therefore, 252 mg/l (0.7 x 360 mg/l).Design:(a) Selection of q c, t and MLSS concentration:Considering the operating temperature and the desire to have nitrification and good sludge settling characteristics, adopt q c = 5d. As there is no special fear of toxic inflows, the HRT, t may be kept between 3-4 h, and MLSS = 4000 mg/l.(b) Effluent BOD5:Substrate concentration, S = 1 (1/q c + k d)= 1 (1/5 + 0.07)qY (0.038)(0.6)S = 12 mg/l.Assume suspended solids (SS) in effluent = 20 mg/l and VSS/SS =0.8.If degradable fraction of volatile suspended solids (VSS) =0.7 (check later), BOD5 of VSS in effluent = 0.7(0.8x20) = 11mg/l.Thus, total effluent BOD5 = 12 + 11 = 23 mg/l (acceptable).(c) Aeration Tank:VX = YQq c(S O - S) where X = 0.8(4000) = 3200 mg/l1+ k d q cor 3200 V = (0.6)(5)(9000)(252-12)[1 + (0.07)(5)]V = 1500 m3Detention time, t = 1500 x 24 = 4h9000F/M = (252-12)(9000) = 0.45 kg BOD5 per kg MLSS per day(3200) (1500)Let the aeration tank be in the form of four square shaped compartments operated in two parallel rows, each with two cells measuring 11m x 11m x 3.1m(d) Return Sludge Pumping:If suspended solids concentration of return flow is 1% = 10,000 mg/lR = MLSS = 0.67(10000)-MLSSQ r = 0.67 x 9000 = 6000 m3/d(e) Surplus Sludge Production:Net VSS produced Q w X r = VX = (3200)(1500)(103/106) = 960 kg/dq c (5)or SS produced =960/0.8 = 1200 kg/dIf SS are removed as underflow with solids concentration 1% and assuming specific gravity of sludge as 1.0,Liquid sludge to be removed = 1200 x 100/1 = 120,000 kg/d= 120 m3/d(f) Oxygen Requirement:1For carbonaceous demand,oxygen required = (BOD u removed) - (BOD u of solids leaving)= 1.47 (2160 kg/d) - 1.42 (960 kg/d)= 72.5 kg/h2For nitrification,oxygen required = 4.33 (TKN oxidized, kg/d)Incoming TKN at 8.0 g/ person-day = 480 kg/day. Assume 30% is removed in primary sedimentation and the balance 336 kg/day is oxidized to nitrates. Thus, oxygen required= 4.33 x 336 = 1455 kg/day = 60.6 kg/h3Total oxygen required= 72.5 + 60.6 = 133 kg/h = 1.0 kg/kg of BOD u removed.Oxygen uptake rate per unit tank volume = 133/1500= 90.6 mg/h/l tank volume(g) Power Requirement:Assume oxygenation capacity of aerators at field conditions is only 70% of the capacity at standard conditions and mechanical aerators are capable of giving 2 kg oyxgen per kWh at standard conditions.Power required = 136 = 97 kW (130 hp)0.7 x 2= (97 x 24 x 365) / 60,000 = 14.2 kWh/year/personReferences[1]Benedict, R. G. and Carlson, D. A. (1971) “Aerobic Heterotrophic Bacteria in Activated Sludge,” Water Research, v. 5, pp. 1023-1030.[2]Curds, C. R. and Fey, G. J. (1969) “The Effect of Ciliated Protozoa on the Fate of Escherichia coli in the Activated-Sludge Process,” Water Research, v. 3, pp. 853-867.[3]Water Environment Association. (1987) Activated Sludge, Manual of Practice #9.[4]Jenkins, D., Richard, M. G.and Daigger, G. T. (1993) Manual on the Causes and Control of Activated Sludge Bulking and Foaming, 2nd ed. Boca Raton: Lewis Publishers.[5]Yasui Hidenari.Recent Developments of the Activated Sludge Process.Kuritakogyo Gikaise,2002[6]SCHULZE K. L. (1965) The activated-sludge process as a continuous flow culture.PartII.Wat.Sewage Wks 112, 11-17.[7]MCI(dNNEY R. E. (1962) Mathematics of a completely mixed activated sludge. J. sanit. Engng Div.Am. Soc. cir. Engrs 88, SA3, 87-113.。
给排水工程外文翻译
给排水工程外文翻译 Final approval draft on November 22, 2020Short and Long Term Advantage roof drainage design performanceDecade has witnessed great changes in the design of the roof drainage system recently, particularly, siphon rainwater drainage system has been gradually improved, and there is likely to be the key application. At the same time these changes, urban drainage system design has undergone tremendous changes, because the scope of a wider urban drainage system design for sustainable development, as well as people for climate change flooding more attention. The main contents of this article is how to design roof drainage systems and make a good performance. Special attention is how to get rid of bad habits already formed the design, but also need to consider innovative roof drainage system, such as green roofs and rainwater harvesting systems.Practical application: In the past few years, the design of the roof rainwater drainage system has undergone tremendous changes. On large buildings, siphon rainwater drainage technology has been very common, as well as green roofs because it is conducive to green development, being more and more applications. Taking into account the ongoing research, this article focuses on how to effectively design a variety of roof rainwater drainage system, and make it achieve the desired design effect.1. IntroductionIn the past decade, the city and the water drainage system design has been widely accepted thinking about sustainable urban drainage system, or the optimal management direction. The main principles of the design of these systems is both a local level in line with the quality of development, but also to create some economic benefits for the investors. This principle has led to the development of new changes in the sump. Although the application of such a device is gradually reduced, but the urban environment relatively high demand areas still require 100% waterproof and rapid drainage, such as the roof. Typically roof drainage system in the design, construction and maintenance has not been given due attention. Although the drainage system investment costs account for only a small portion of the total construction investment, but not able to judge the loss caused by poor design.There are two different forms of roof drainage system design methods, namely the traditional and siphon method. Traditional systems rely on atmospheric pressure work, the drive ram affectedsink flow depth. Therefore, the conventional roof drainage systems require a relatively large diameter vertical drop tube, prior to discharge, all devices must be connected to the groundwatercollection pipe network. In contrast, siphonic roof drainage pipe systems are generally designed to full flow (turbulent flow meansthat require less exhaust pipe), which will form a negative pressure, the larger the higher flow rate and pressure head. Typically siphon system requires less down pipe work under negative pressure to the water distribution network can mean higher altitude work, thereby reducing the amount of underground pipe network.Both systems consists of three parts: the roof, rainwater collection pipes, pipe network.All of these elements are able to change the water pressure distribution system. This section focuses on the role and performance of each part. Due to the principle of siphon system has not been well understood, resulting argument is relatively small, this article will highlight siphon system.2. RoofThe roof is usually designed by the architect, designer and not by the drainage design. There are three main roof.2.1 Flat roofFlat roofs are used in industrial buildings less rainfall regions and countries. This roof is not completely flat, but lower than the minimum roof slope may require. For example, the United Kingdom require maximum slope of 10 °. Setting minimum slope in order to avoid any unnecessary water.Despite the flat roof if it is not properly maintained will have more problems, but it will reduce the dead zone within the building, and the ratio of sloping roofs in favor of indoor air.2.2 sloping roofsMost residential and commercial buildings are pitched roof, inclined roof is the biggest advantage can quickly drain, thereby reducing leakage. In temperate regions, we need to consider carrying roof snow load. Once it rains, rainfall through the sloping roofs can be determined by calculation. When rainfall data can be used, you can use the kinematic theory to solve such problems.2.3 green roof (flat or inclined)It can prove roof is the oldest green roofs, including rainfall can reduce or disperse roof planted with plants. It can be planted with trees and shrubs roof garden, it can also be a vegetated roof light carpet. Wherein the latter technique has been widely used. Some of these applications tend to focus on aesthetic requirements and are often used in green development. Since the aesthetic requirements and pressure requirements, as well as green roofs thermal insulation function, reduce the heat island effect, silencer effect, extend the life of the roof.Green roofs in Germany, the most widely used, followed in North America, but to consider the impact on the aesthetics. Germany is by far the most experienced countries in the 19th century have practical application, then as an alternative to reduce the risk of fire tarroof an option in urban areas. Germany is currently the main research question on the cultivation of other issues to consider smaller cities. A study from 1987 to 1989, was found packed with 70 mm thick green roof can be reduced by 60% -80% of heat loss. In a Canadianwork computer model based on the roof indicates that as long as the sump, the area can reach 70% of the roof area can be reduced by 60 percent in one year, the same model was also used for artificial rainfall, which the results indicate that rainfall in the catchment season helps to drain away rainwater.However, none of these studies show that green roofs can play a useful role in the rainfall season, or how high collection efficiency of water supply. The United States did some tests, as long as the green roofs regular watering, can reduce 65 percent of the runoff ina rainfall. America's most authoritative green roof guidelines by the New Jersey state environmental agencies promulgated. The mainprinciple is to solve the structural problems of light, and how can the normal drainage after two years.Rainfall period is based on the probability of failure is determined. The system is typically based on rainfall during rainstorms two minutes, two minutes, have a choice. Although this model will get more traffic, but there is no other better alternative. Studies have shown that the traditional model is applied to study green roofs are premature.Loss factor than traditional roof records should be small, about 98.7%.Peak flow will be reduced, although not penetrate, the surface roughness but also have a significant impact.Concentrated rainfall than two minutes for a long time,especially for large roof areas, such as public buildings, commercial buildings, industrial buildings.Urban drainage design should also consider other factors, for a complex system, a green roof in a rain is not enough. Water flow duration curve shows a longer than traditional systems. And two independent and will affect between is possible, which requires a more precise time period.3. Rainwater CollectorBasic requirements rainwater collector is designed to be able to accommodate rainfall rainstorms. Although it is possible to make a slightly inclined roof drainage purposes, but the nature of the construction industry and building settlement will become flat roofTypically, the tank is placed in a horizontal, sectional view of the water is outwardly inclined, which the role of hydrostatic.3.1 drain outletAnalyzing rainwater collector has sufficient volume is the key to the sump outlet external setting conditions. Also affect the flow rate into the storm water drainage system piping, but also affect the depth of the water catchment. Although the depth of the sump will not bring any particular problems, but too deep can cause excessive sump.Numerous studies in the 1980s showed that the flow of conventional roof drainage system outlet can be divided into two cases. It depends on the size of the depth and size of the outlet. When the water depth is less than half the diameter of the outlet, the flow of the first type, and the outlet of the flow can be calculated by an appropriate equation; water depth increases, exports are slowly clogging the flow will become another form forms, at the same time, the flow of exports can be obtained through other equations. While conventional roof drainage systems are designed to be free-draining, but may cause limitations encountered in the design of the flow is not free. In this case, it will require additional depth.Siphon roof drainage systems, the outlet is designed to be submerged stream. In this case, the depth of the outlet of the decision is more complicated, because the design of the sump depends on the flow. Recent studies have shown that conventional roof drainage systems use a variety of non-standard catchment, their depth and height, bigger than the diameter of the outlet. This will eventually result in a siphon effect. For a given catchment, the flow depends on the starting end of the drop tube diameter. A similar phenomenon has also been used to study the standard catchment, in these circumstances, only limited siphon action occurs within relatively close distance from the exit.3.2 tank flow classificationIn the complex flow sump outlet flow classification, can be seen from Table 2a, the flow will be uniform layering, regardless of whether the same inlet flow. Table 2b and 2c show, exportdistribution will greatly influence the flow.When the outlet is not a free jet, sump outlet complex flow classification is difficult to describe. Because each catchment tank pressures are likely to be merged. For example, the siphon tube system design point is at near full jet outlet flow classification depends on the energy loss of each branch.3.3 hydrostatic sectionalSump shape of the water surface in the canal can be classified according to the flow equation. In most cases, a low flow rate meansthat there is less friction loss, if exports are free jet, thefriction loss is negligible cross-section through the hydrostatic equation 1 to determine the horizontal distance.Where Q-- flow (m3 / s)T- surface width (m)g- acceleration of gravity (m / s2)F- flow area (m2)Equation 1 can not be ignored when the friction required to correct (or very long pipe velocity is large), or not a free jet.3.4 The current design methodsThe previous discussion has highlighted the main factors that should be considered with sink design. However, without the help of a certain number of models, computing hydrostatic sectional roof drainage system, the volume of the sump is possible. This large commercial and manufacturing industry, is a development opportunity, you can merge several kilometers of water routes. Thus, the conventional drainage system sump design methods are mainly based on experience, and assume that exports are free jet.Sump location in the building, it may cause the example to fail. Different interface sumpExcept in the case cited above, but also allows designers to use empirical data.3.5 Digital ModelLarge number of digital models can be used to accurately describe the flow of any form of catchment tank, regardless of whether the roof flows stable. An example of this model is a combination of roof space model. This model enables users to classify different aspects of the data indicated, includes: details of the rains, the roof surface drainage and other details. Kinematics have also been used to study rainwater tank to flow from the research collection. A typical method is based on open system to solve a basic problem of spatial mobility. This model automatically resolve the sump outlet flow situation, but also to deal with the case of free jet can also be simulated space limited mobility and submerged discharge. Output values include depth and flow rate.Currently, the model is essentially just a variety of research tools, but also through practical engineering test. However, we should face up to the various role models.4 pipe systems groupComposition in the form and scope of the tube group determinesthe roof drainage system relies mainly on the traditional system or siphon action.4.1 Traditional stormwater systemsConventional roof drainage systems, the ground plane is generally vertical pipe-line network, connected to the sump outlet and underground drainage systems, critical systems as well as compensating tube. It should be emphasized that the angle between the ground and the compensating tube is less than 10 °. Capacity of the entire system relies mainly on the outlet tube instead of down.Flow vertical tube is usually free-flowing, full of only 33%, the efficiency depends on the excess length of the tube. If the drop tube long enough (typically greater than 5m), there may be an annular flow. Similarly, under normal circumstances flow compensation pipe is free-flowing, full of up to 70%. Such designed process both for the design, various equations can also be used.4.2 Siphon roof drainage systemIn contrast with the traditional drainage systems, Siphon roof drainage system relies on air flow outside the system, and the tubeis full pipe flow stream.The designs are usually made on the assumption that the design of heavy rain, the system can quickly siphon discharge rainwater. This assumption allows the application of hydrostatic siphon system theory. Often used steady flow energy equation. While this approach ignores the small amount of energy loss at the entrance, but after the experiment showed that there are still conducive to practical use.However, steady-state design methods in the siphon system is exposed to rain when the system does not meet the standard requirements or changes in rainfall intensity is large is not applied. In the first case, there will be some mixing of air quality, annular flow occurs. These problems are not integrated in the system when more serious. Because usually designed rains are common, it is clear now design methodology over time may not apply to siphon system. This is a major disadvantage, because the design of the main problem isthe noise and vibration problems.Despite the disadvantages of the prior design approach, but a lot of the world's very few engineering failure reports. When a failure occurs, most likely for the following reasons:An incorrect understanding of the operation pointsSubstandard materials listInstallation defectsMaintenance mismanagementTo overcome these disadvantages, we have recently launched aseries of research projects, to discuss the siphon system, and the development of digital models. From this work we learn a lot.In contrast with conventional design methods of some assumptions, siphon system mainly has the following aspects:1) non-flow system of full flow2) levels of certain pipe-flowing full pipe flow3) full pipe flow downstream propagation through a vertical pipe, riser, etc.4) the inner tube flow occurs over the vertical section, the system to reduce the pressure5) downward tube is full pipe flow, there will be air lock6) appears completely siphon action until well into the air system is lower than a certain levelTable 4a column data indicate that below the design point, the system will siphon unstable flow, depth of the water collecting tank is insufficient to maintain the siphon action. Table 4b show that the unsteady flow in siphon system when it will appear.Table 5 lists the data output of a digital model. It can be seen that the model can accurately describe the siphon action, siphon and steady state, the data also show that the model can accurately describe the complex siphon action.5 ConclusionThis article has illustrated the critical roof drainage systems, but these are often overlooked in the urban drainage system design. This article also shows that the design process is a complex process, rely mainly on the performance of exports. The following conclusions are based on the design summed up:1) Run depend on three interacting parts: the roof, sump, water pipes2) Green roofs can reduce traffic and beautify the city3) the export performance of the system is essential4) siphon drainage system have a greater advantage in large-scale projects, but must be considered high maintenance costs5) Design siphon drainage system should consider additional capacity and operational issuesAlthough the green roof is a more attractive option, but the traditional roof of a building in the country will continue to dominate. Green roofs will be gradually developed, and gradually been widely accepted. Similarly, the roof drainage system shown effective that it will continue to play a huge role in the commercial building drainage systems.Roof drainage system of the greatest threats from climate change, existing systems tend to be not simply aging; rainfall patterns of change will result in inefficient operation, self-cleaning rate will be reduced. Changes in wind speed and the roof will also accelerate the aging of the roof, it is necessary to carry out maintenance. Taking into account the climate change, the increase in materials, roof collected rainwater will be more extensive. Currently, the amount of rain around the globe per person per day 7-300 liters in the UK, with an average consumption of 145L / h / d, of which onlyabout one liter is used by people, about 30 per cent of the toilet, study shows If water shortage, rainwater collected on the roof of developed and developing countries are recommended approach.屋顶排水设计性能的近期与远期优势最近十年见证了屋顶排水系统设计方面的巨大变化，特别的是，虹吸雨水排水系统已经得到逐步改善，并且有可能得到重点应用。
土木工程给水排水英文文献及翻译-英语论文
土木工程给水排水英文文献及翻译-英语论文土木工程给水排水英文文献及翻译Building drainage of water-saving techniquesWith people's quality of life，the quality and quantity of water are constantly expanding. Implement sustainable water use and protection of water resources from destruction. And access to healthy water, recycling of water, has become the government and the broad masses of the people the focus of attention. All this gave to the construction of drainage works on the design of the many new requirements, water supply advanced technology of the urgent need to accelerate the pace. This paper will explore more of the building for drainage of water-saving technology; we hope to arouse the awareness of water conservation to build water-saving city efforts.Construction of a water-saving project, in addition to the water saving should formulate laws and regulations to strengthen the management and day-to-day publicity and education use price leverage to promote water conservation work, but also take effective measures, to ensure that the construction of water-saving work carried out in-depth and comprehensive. We are aware that the water supply network's coverage, the extension of transmission mains and the construction of the building because arisingfrom the difference in height, will be used to increase the water pressure before the end of ways to protect the most disadvantaged water points will be adequate water supply, This will be a large number of regional supply of high pressure water supply is. Therefore accessories before the water hydrostatic head greater than outflow, the flow was greater than the rated flow capacity. Beyond the rated flow capacity of that part of the normal flow did not have the use efficiency is a waste of water. As a result of this water is being wasted is not easy to detect and understand, it could be called a "stealth" wasting water.It has been in a different type of floor, the building 67 water distribution points so the overpressure from the measured flow analysis, Statistical results are 55% of the iron spiral movements - taps (hereinafter referred to as "ordinary water") and 61% of the ceramic valve - leading the flow of water-saving more than their rated flow, the super-flow pressure from the state. Two endings the largest flow out of the rated flow capacity of about three times [1]. This shows that in our existing buildings, water supply system overpressure out-flow phenomenon is widespread and it is a fairly serious. In distribution point pressure As overpressure flow out of the "invisible" water is not wasted paid enough attention to, So in our existing "building water supply and drainage design" and "construction water supply and drainage design GBJ15-20 00 draft "(hereinafter referred to as" draft "), although the wateraccessories and home support the greatest pressure certain restrictive provisions in [2], but this is only to prevent water from the high pressure parts will lead to damage to the point of consideration, not prevent excess pressure from the out-flow point of view, the pressure is too lenient restrictions on the flow overpressure no fundamental role. Therefore, in accordance with the water supply system overpressure flow from the actual situation, the pressure on the water supply system to make reasonable limit.1.2 measures taken decompressionWater supply system in a reasonable allocation of decompression device is to control pressure within the limits required to reduce excess pressure from the flow of technical support.1.2.1 Jangled nervesRelief valve is a good decompression device, can be divided into proportional (lower left) of direct action and the type (Photo) The former is based on the ratio of the area to determine the proportion of decompression, which can be set under pressure prior decompression, When the water-stop water, you can also be controlling the vacuum tube pressure is not increased, Decompression can achieve dynamic can achieve static decompression.1.2.2 Decompression orifice and conserving Cypriots1106土木工程给水排水英文文献及翻译Orifice decompression compared with jangled nerves example, the system is relatively simple, less investment, easy management. The practice of some units, water-saving effects are fairly obvious, If Shanghai Jiao tong University in the school bathroom water pipe installation aperture of 5 mm orifice, water-saving about 43%. But decompression orifice only by the dynamic pressure, static pressure can be reduced and the pressure downstream with the upstream pressure and the flow is changed, is not stable enough. In addition, the vacuum orifice plug easy. In better water quality and water pressure more stable, by using [3]. Cutting expenditure and the role of Cypriot advantages and decompression orifice basically are the same. Suitable for the small diameter and accessories installed to use [3].1.3 adopt water-saving leadingA trial showed that the leading Practical water-saving taps and the general state of the full, flow out of the former than the latter out of the flow. That is the same pressure, the leading water conservation has good water saving, water-saving volume in 20% ~ 30% between. And the higher the pressure ordinary tap water from the larger, water-saving is leading the greater the volume of water-saving. Therefore, should the building (especially in the standard water pressure in water distribution points) leading installation of water-saving, reduce water wastage. In 1999 theMinistry of Construction, State Economic and Trade Commission, State Bureau of Building materials apparatuses jointly issued a document "on the elimination of residential buildings behind the products notified" require large and medium-sized cities in new residential prohibit the use of helical-style cast iron nozzle movements, actively adopt "ceramic cartridge faucets" and "common faucet technical conditions of the ceramic cartridge faucets [4]. Since the main building of our school building earlier in the toilet faucet is still an ordinary spiral movement - iron taps. We have often seen leading loosening and tightening the leading difficulty caused by the leakage phenomenon. In fact, there is such a faucet overpressure caused by the "invisible" huge waste of water. Schools should arouse the concern of the relevant departments, from the long-term interests for the use of water-saving new leader, reduce unnecessary losses.2 vigorously develop the construction of water facilities, "watercourse." As the name suggests is not delivered on the waterways clean water is not sullied by sewage contamination. Residents put a wash, bathing, washing clothes and other water washing and flushing water together, after CO., filtration and disinfection, Sterilization, which imported waterway network, for toilet flushing, washing cars, and pouring green, onto the road and other non-drinking purposes. China therefore waterway is also known as miscellaneous water Road. With a watercourse which cubic metersof water, equivalent to the use of one cubic meters of clean water, emit less nearly a cubic meter of sewage and kill two birds with one stone. Water-saving achieved nearly 50% [3]. Therefore, the channel has many of the world's water shortage in cities used extensively.2.1 full use washing wastewater and other quality miscellaneous drainage The existing water facilities built in most hotels, colleges, and the basic source for the bathroom bathing wastewater. For some small units, smaller than bathing wastewater, and discharge time is too concentrated, Water facilities are not stable and adequate source of water. And washing with water wastewater, the use of time more evenly, water treatment and the advantages of relatively good, as a water source, to be fully exploited.2.2 Develop and implement as soon as possible the return to the new water quality standardsThe current construction of water reused implementation of the existing “life miscellaneous water quality standards.” The total coli form standards and the requirements of "sanitary standard for drinking water," the same, compared to the developed countries and the Chinese water standards apply to the swim-minus III also strict standards. This has led to two problems: First, many of the existing water works is less than the standard; 2 are fulfilled with a certain degree of difficulty, improvethe water project investment and processing cost. So should develop appropriate indicators of the value of water works to promote the spread土木工程给水排水英文文献及翻译and popularize. Water Saving water is not limiting, or even prevents the water. But reasonable people to water, efficient use of water and not waste. As long as we pay attention to fit the family's bad habits, we will be able to water-saving around 70% [3]. Water and waste a lot of the habits, such as: flush toilets single wash cigarette butts and broken fine waste; to access a cup of cold water. Many people will not venting water; spend the potatoes, carrots after peeling, washing or after the optional vegetables; when the water stopped (open access customers, answer the phone, change TV channels), not turning off the tap; During the suspension, forget turning off the tap; toilets, wash, brush, let the water has been flowing; Before sleep, go out, do not check the faucet; equipment leaks, not promptly repaired. From the following table, we can see in many parts of life as long as we interested to note that the conservation of water is very impressive.3 to promote the use of water-saving devicesIn addition to the family of water-saving attention to cultivate good habits of water, using water-saving devices is very important and also the most effective. Some people prefer laissez-faire, but also refusedto replace water-saving devices, in fact, so much water is a long time down the uneconomical. Thus vigorously promote the use of water-saving devices is the construction of water-saving important ways and means.3.1Water-saving taps3.1.1 Water Saving leading CeramicsCurrently most of the water-saving taps used Ceramics taps. Such taps compared with ordinary taps, water was typically up to 20% ~ 30%; and other types of water-saving compared to the leading and cheap [3]. Therefore, in the residential buildings of architectural vigorously promote the use of such water-saving lead. We taught the fifth floor of the dormitory building and are used by such leading.3.1.2 Closed since delay tapsSince the delay in the water taps closed after a certain time, shut down automatically to avoid Changliushui phenomenon. Water timing to be in a certain range adjustment, both for the convenience of Health has complied with the water-saving requirements suitable for washing in public places with.3.1.3 Photoelectric controlled tapsClosed since the delay of water-saving taps but water while fixed time and meet the different requirements of the use of the object. Photoelectric controlled taps will be able to overcome the above drawbacks, such as the latest one of the type of infrared device control wash, Thefirst installation will be self-inspection of the device in front of or below the fixed reflectors (for example, vanity) and based on the reflectors adjust their distance from work to avoid the past because of automatic water obstacles closer to the front of regular water, Such intelligent device can wash your hands although below action without washing their hands without water. a long time will wash water and do not have long-term can also regularly flush Water Seal failure to avoid a supply shortage ahead of the police [3].3.2The total water-saving flush3.2.1 Use of small volume cisterns commodeChina is promoting the use of water tanks 6 L fecal water-saving devices, and have flushing water to 4.5 L or even less, stood on the stool available. However, we should also pay attention to the drainage system to ensure the normal work of the use of small volume cisterns commode, otherwise they will be brought to plug the pipeline, not a net wash, and other issues. Two respectively flushing cisterns in urine, flushing water for 4 L (or less); Washing stool, Chong stood at 9 L (or less) [3]. (Map is a two-valve I-Yuan annually to the water tanks, to open the stool below the drain urine when opened above the drain Pictured left is the two-block cisterns switch several forms) Israel's construction regulations require all new buildings to install two respectively wash cisterns. China should also vigorously promoted two respectively cisterns, because one day, thenumber is far higher than the urine stool frequency. To three homes as an example, per person per day for a meeting of feces, urine four times and the use of existing water tanks L 9, day to 135 L of water; 6 L of water use, 90 L of water a day;土木工程给水排水英文文献及翻译and the use of cisterns two respectively, 75 L of water a day, can be seen using two respectively cisterns 9 L 6 L than using more water-saving cisterns [3]. 6 L Yuan annually to the use of water-saving cisterns better results. The use of tanks in two trances another advantage is not right and the replacement of the total drainage system to carry out reform therefore particularly applicable to existing buildings the total replacement of water tanks.3.2.2-washing UrinalThe United States launched the Urinal-washing, which is not water, the stench from the toilets without using utensils, In fact, only in one end Urinal add special "trap" devices, but because the economic, health, water effectively, So popular station.3.2.3Photoelectric control UrinalUrinal photoelectric controls in a number of public buildings installations.3.2.4 Delayed flushing valve closedIt is the use of guide-work principle, water officials directly connected with the water pressure high enough circumstances, can protect the instantaneous flushing commode needs to replace tanks and accessories, installation is simple and easy to use, health, low prices, Water-saving effect of the obvious characteristics [3]. We carpentry center is used for such cleaning.3.3 in hot water systems installed in various forms of water-saving devicesIf installed in public bathrooms limited flow orifice, in the cold, hot water imported pressure balance between the installation of equipment; Installation of low-flow plumbing. Inflatable hot water thermostat and cooling, hot water mixed hydrants.3.4 to further develop various forms of water-saving devices3.4.1 Development of different water taps outSome countries, in different places with different water out of taps, Singapore provides water for washing vegetables pots 6 L / min, shower water 9 L / min; China's Taiwan Province launched the spray-wash special taps, the flow was 1 L / min. In China, various taps most of the rated flow capacity of 0.2 L / s, that is 12 L / min, excessive [4]. Therefore be reasonable to develop taps the rated flow, and gradually installed in different places different from water taps.3.4.2 Vacuum water-saving techniquesTo ensure that sanitary ware and sewer cleaning effect of vacuum technology can be applied to drainage works Most of the air instead of using water, relying on the vacuum of high-speed gas-water mixture, and rapid disposal of the sewage, dirt-gully clean and save water and drain away the effects of dirty air. A complete vacuum drainage system, including: vacuum valve and with a magnitude of suction devices occupants, the closed aqueduct, vacuum collection containers. Vacuum pumps, control equipment and channels and so on. Together with the vacuum generated 40 ~ 5min the negative pressure of sewage pumped to the collection containers, then will collect sewage pump effluent into the municipal sewer. Different types of construction in the use of vacuum technology, the average water-saving exceed 40%. The use of the office building water-saving will rate-70% [2].3.4.3 Development zone leading to the wash waterIn Japan, many families use with the leading water wash, wash all the wastewater into water tanks for back flushing. If the water tank, they can directly turn on the water faucet open. Irrigation water use, it can not only save water but also reduce the costs. At present, the water in China has sales.土木工程给水排水英文文献及翻译随着人民生活质量的提高，对供水量和质的要求正不断扩展.同时实施水的可持续利用和保护，使水资源不受破坏，并能进入良性的水质、水量再生循环，也已成为政府和广大人民群众关注的焦点。