车辆工程机动车离合器的外文文献翻译
湖北文理学院
毕业设计(论文)英文翻译
题目有限元热分析的陶瓷离合器
专业车辆工程
班级Xxx
姓名Xxxx
学号2010138xx
指导教师
职称Xxx 副教授
2014年2月25日
Fethermal analysis of a ceramic clutch
1. Introduction
Abrasive dry running vehicle clutches are force closure couplings. Torque and speed transmission are ensured by the frictional force generated between two pressed surfaces. Reasons for the application of ceramic as a friction medium include good heat and wear resistance properties, which provide the opportunity to drive higher pressures, and a low density. Thus, an increasing power density is enabled with a parallel minimization of construction space.
Measurements with a first prototype of a clutch disk using ceramic facings were performed at Karlsruhe University in a laboratory specialized in passenger car drive system testing. In the course of analysis the finite element (FE) model was to be constructed with the knowledge of measurement data and measurement conditions. Calculations were intended to determine the temperature distribution of the clutch disk and its environment at each moment in time corresponding to measurements. It is essential to be familiar with the temperature range in order to examine the wear characteristics of the system. Thus, important information is derived from measurement data. In critical load cases, the highest expected temperatures must be forecast in space and time in order to protect measuring instruments close to the location of heat generation.
The goal of this study is to analyze and modify the clutch system to
provide better operating conditions by improving the heat conduction and convection of the system or to increase the amount of the energy converted into frictional heat. Furthermore, it is desired to find better design solutions for more efficient clutch systems.
Calculations were performed by the Cosmos Design Star software. During model development, great care had to be taken for proper simplification of geometry, the selection of element sizes, and the correct adjustment of time steps due to the substantial hardware requirements for transient calculations. Changes in thermal parameters such as the surface heat convection coefficient and thermal load had to be taken into consideration on an on-going basis in terms of time and location. The two sides of the analyzed test clutch system can only be managed by two independent models linked by heat partition, according to the hypothesis that the contact temperature must be identical on both sides while there is proper contact between them and its value must be adjusted by iteration. Calculations revealed that the heat partition changed by cycle and it differed along the inner and outer contact rings. As a result of the different cooling characteristics between the ceramic and steel side, a heat ?ow is launched from the ceramic side to the steel side. This heat flow was also determined by iteration, its value also changes by cycle and differs along the inner and outer contact rings.
2. First prototype of a clutch using engineering ceramics as
friction material
The examined clutch disk was developed according to the “specific ceramic”product development process established at the Institute for Product Development (IPEK) at the University of Karlsruhe. This development process already has the possibility for connection to a real transmission shaft; further, it has a cushion spring device for the facings allowing good start behaviour. Abrasive clutches must comply with the following basic requirements:
●high torque transmission according to high friction coefficients,
●high comfort (no vibrations through self-induced chattering),
●homogeneous temperature distribution,
●low wear characteristic.
A critical element of the switch is the abrasive disk.With regard to the design utmost care must be taken to select the right material. A high and constant friction coefficient,，wear resistance and thermal resistance are desired characteristics. The clutch disk has instead of the generally applied ring-shaped abrasive inlet two rows of SSIC (as sintered) ceramic pellets. These pellets are placed on 6 separate segments. The segments are ?xed to the central hub by rivets. Each segment consists of 4 plates, 2 working as facing springs and 2 as carriers.
3. Measurements
Measurements were performed at the department of power train
development of the Institute for Product Development (IPEK) at the Karlsruhe University (TH) Research University, where a category IV component test rig is used for tests of new frictional materials and examinations of new materials in real clutch disks. Real conditions are applied by the simulation of driving resistance (e.g. starting in the plane, starting at the hill). It is a component test rig leveled on the fourth position of the tribological testing environment.
In order to give an idea of dimensions: the equipment length is about 4-5m. The two electric motors and the axial force are controlled independently by computer; thereby many operational states can be realized. This enables the equipment to complete a myriad of tribological measurements all while properly modeling the operation of a clutch disk in a passenger car. It is also equipped with an automatic IT measurement system. Measurable quantities include the following:
●two heavy-duty electric motors (150 KW, Baumuller DS 160L-305),
●device suitable for exerting axial force,
●torque meter (Manner Sensortelemetrie MF100),
●axial force meter,
●steel disk in friction,
●replaceable head to affix the device to be tested,
●temperature along two different radii at 0.4mm below the abrasive
surface of the steel disk (Omega
HJMTSS-IM100U-150-2000,J-typeiro-constantan thermocouples),
revolutions per minute for both sides (Polytene LSV 065).
The greatest challenge out of these is temperature measurement as we would like to know the temperature of the revolving steel disk. The two thermoelements placed in the steel disk forward data to the computer through a wireless blue tooth system and are placed 0.4mm below the abrasive surface of the steel disk on the two opposite arcs of the clutch disk.
3.2. Measurement process
Due to component analyses and cost reduction only one side of the clutch disk is mounted with ceramic facings. Thus, the clutch disk and its fitting will be referred to as the ceramic side, and the abrasive steel disk with its environment revolving together will be referred to as the steel side. In the course of measurements, data were collected at a sampling frequency of 100 and 1000HZ. Measurements were conducted according to the time curves.
The measurement starts by increasing the revolutions per minute of the steel side (the driving side) to a specific value (1500 rpm here). Then the ceramic side (the driven side), held at zero rpm, is pushed towards the steel disk and the axial force is applied until a designated value is reached (nominally 4200N here). Upon reaching the designated axial force the ceramic side is released and the two sides start to synchronize. A few seconds after synchronization, the axial load is discontinued and after some time both the steel and the ceramic sides—revolving at the same speed—are slowed down. This is deemed to be one measurement cycle. T en cycles are
completed in the course of a single measurement. During application of the axial force the ceramic side is held at zero rpm until the desired force is reached to ensure synchronization occurs at nearly the same time of each cycle. This is unfavorable from the viewpoint of both measurements and calculations. Measurements are usually conducted by changing only 3 parameters: the speed, the axial load and the inertia. The following figures are applied in various combinations:
●speed n: 700, 1100 and 1500 (rpm),
●axial force F: 4200, 6400 and 8400 (N) and
●inertia I: 1, 1.25 and 1.5 (kgm2).
Experimental measurements are launched with approx.10-15 min intervals, during which the system cools down to about 30-40 1C. This makes calculations difficult, as the exact temperature distribution of the system is not known at the commencement of the measurement. However, it can be assumed that a period of 10-15min is sufficient for a nearly homogeneous temperature distribution to be produced. The parameters for the following simulation have been chosen for an intermediate case with a speed n =1500 rpm, an axial force F = 4200 N and an inertia I = 1 kg m2.
4. Calculations of heat generation
The mechanical energy consumed during the friction of two bodies is transformed into heat. The generated heat can be calculated by the following simple formula: Q =μ·ν·F [W] .
where m is the the frictional coefficient; v is the sliding velocity; F is the force perpendicularly compressing the surfaces. And the heat flux density per surface unit is q=μ·ν·p [Wm2].
where p is the the pressure calculated as a ratio of the force and the contacting surface. As the ceramic tablets are placed at two different radii along the clutch disk, the heat generated must be calculated separately for each radii. Sliding can be divided into two sections. In the first section, the ceramic side is kept in a stationary position by braking, meanwhile the axial load is increased; therefore compression changes in the course of time while the speed difference between the two sides is constant. In the second section (at synchronization) the speed difference is equalized while the force value is constant, so velocity changes in time. On the basis thereof, the heat generated is
.
The nominal contact area is the aggregate of the contacting surfaces of the 24 and 18 ceramic tablets on the given ring. The diameter of ceramic tablets is:
.
Calculations were performed for the load case to be characterized by the
following parameters:
.
Based on experimental measurements a constant friction coefficient of 0.4 was established.
.
The velocity can be calculated with the knowledge of the radius and the speed.
.
Surface pressure can be calculated as a ratio of the axial force and the contacting surface. This produces the same figure for each ceramic pellet, assuming an even load distribution.
.
Thus, the maximum values of the generated heat are
.
In the first section of sliding, the generated heat is rising due to the increase of the load force; in the second section, it is decreasing due to the equalization of the speed difference. It is necessary to know the time of each
sliding section in order to be able to specify the generated heat time curve. These can be determined from measurement data series. Synchronization time can be easily determined from the speed of the ceramic side. Speed increase is linear. Force increase is non-linear. For the sake of simplicity, force increase was substituted by a straight line in calculations so that the area below the straight line is nearly identical with the area measured below the curve. Thus, the time difference between the two terminal points of the straight line is the time of the first sliding section.
The above-mentioned method was applied for each cycle and their average was specified. Based on these results, the following values were determined for sliding times:
.
Now the time curve of heat generation can be produced. The same curve was used in each cycle as there were no significant differences between parameters in each cycle. The generated heat-calculated this way-will appear as thermal load in the thermal model. It must be distributed appropriately between the contacting surfaces by taking into consideration heat partition. Heat partition requires the contact temperatures to be identical at both surfaces. Correct adjustment requires repeated iterations.
有限元热分析的陶瓷离合器
1 引言
磨料空转车辆离合器是力封闭联轴器。扭矩和高速传输被压紧表面之间产生的摩擦力所保证。应用陶瓷是因为它作为摩擦介质具有好耐热和耐磨损性能，提供了机会以驱动更高的压力，以及一个低的密度。因此，一个提功率密度启用了一个平行的最小化建筑空间。
测量使用陶瓷饰面离合器盘的第一个原型在卡尔斯鲁厄大学的一个实验室专门从事客车驱动系统进行了测试执行。在分析过程中的有限元（FE）模型是将与测量数据和测量条件的知识所构成。计算的目的是要确定在离合器盘上温度的分布以及环境中的在每一时刻的及时测量目。至关重要的是熟悉的温度范围，为了检验该系统的耐磨特性。因此，重要信息从测量数据中得出。在临界负载的情况下，预计最高温度必须在时间和空间上进行预测，为保护接近发热体的位置测量工具的。
本研究的目的是分析和修改该离合器系统通过改进，以提供更好的工作条件热传导和系统或增加转化成摩擦热的能量的对流。此外，人们希望找到更有效的更好的离合器系统设计方案。
计算是由宇宙星空的设计的软件进行的。在模型开发阶段，非常谨慎，必须采取几何元素，选择适当的简化尺寸，并且由于正确调整的时间步长大量的硬件要求瞬态计算。热物性参数的改变，如表面热对流化系数和热负荷，必须考虑到到在一个持续的基础上在时间和地点方面。离合器系统的分析测试这两方面，只能通过加热隔板连接的两个独立的模型来管理，根据该假说认为，接触温度必须是在两个相同的双方，同时他们要有适当接触，其价值需通过迭代来进行调整。计算显示，该热分区按周期变化，它沿不同的内，外接触环。在不同的冷却特性下，在陶瓷和钢之间的结果是不
同的，热流从陶瓷侧面向钢侧流动。此热流也通过迭代确定;它的价值也改变了周期和不同沿着所述内和外接触环。
2 采用工程陶瓷作为摩擦材料的第一个原型机
这款检查过的离合器盘是根据“特定的陶瓷”产品而开发的，此材料的研发过程在流程在卡尔斯鲁厄大学的Institute for Product Development (IPEK)杂志上发表过。此开发过程已经具有的可能性，用于连接到一个真实的传动轴；甚至，它为面板有一个好的初始行为起到一个很好的缓冲作用。磨料配件必须符合以下基本要求：
1.根据高摩擦系数高扭矩传递
2.高舒适度（通过自感应抖动无共振）
3.均匀的温度分布
4.低磨损特性
开关的一个关键因素是摩擦面.在设计极限方面，必须谨慎采取选择合适的材料。高而恒定的摩擦系数，耐磨损和耐热性是理想的特性。离合器圆盘能代替通常应用环形磨料入口两排SSIC的（烧结）陶瓷颗粒。这些小球被放置在6个单独的段位。该段由铆钉固定到中心轮毂。每个段由4片组成，2个工作面对着弹簧和2个作为载体。
3 测量
3.1 测量设备
测量是在卡尔斯鲁厄大学（TH）研究型大学的动力传动系完成的，同时也是用于测试新的摩擦材料和新材料在实际离合器片中检测的地方。真实情况是通过驱动电阻的仿真应用（例如，开始在平面上，开始于山）的试验装置。这是一个组件试验台夷为平地在摩擦测试环境的第四位。为了给维度的概念：设备长度大约4-5m 。两台电动机和轴向力是由计算机独立控制;因此许多运营可实现的状态。这使得设备来完成
一个摩擦学测量无数，而所有正确建模在乘用车上的离合器盘的操作。它还配备用自动的IT测量系统。可测量的量包括以下内容：
1.2个重型电机（150千瓦，Baume米勒DS160L-305）
2.设备适用于施加轴向力
3.扭力计（Sensortelemetrie MF100）
4.轴力计
5.钢盘的摩擦
6.可更换的头部贴上设备进行测试
7.温度沿两个不同的半径处为0.4mm以下的钢盘（欧米茄HJMTSS-IM100U-磨料
表面150-2000，J铁康铜热电偶）
8.每分钟转数为双方（Polytec LSV065）。
这里最大的挑战是这些我们想知道的旋转钢盘面上温度的测量。两个热元件放置在钢盘通过无线蓝牙数据转发给计算机系统和被放置为0.4mm以下的研磨面钢盘上的两个相对的圆弧的离合器盘。
3.2 测量过程
为了测量由组分分析和降低成本的一侧离合器盘安装用陶瓷衬片，由此，离合器磁盘及其配件将被称为陶瓷侧，而磨具钢盘与它的环境一起旋转会简称为钢侧。在测量时，数据的过程中收集在100和1000Hz的采样频率。
在测量开始通过增加每转钢侧（驱动侧）的分钟为一个特定值（这里是1500转）。然后在陶瓷侧（驱动侧），在保持零转速下被推向钢盘和轴向力应用，直到一个指定的值为止（名义上4200N在这里）。当到达所指定的轴向力的陶瓷侧是释放和双方开始同步。几秒钟在同步之后，在轴向载荷终止和后一段时间都在钢和陶瓷两侧绕转在
相同的速度会慢下来。这被视为一个测量周期。十个周期中的一个过程中完成单次测量。在应用程序中的轴向力陶瓷侧被保持在零转速，直至所需的力达到以确保发生同步于几乎每种相同的时间周期。这是不利的从两者的观点出发，测量目和计算。测量通常通过进行仅改变3个参数：速度，轴向载荷和惯性。下面的数字是应用于各种组合：
1.转速n ：700 ，1100和1500（RPM ）
2.轴向力F ： 4200 ，6400和8400（N ）
3.惯量I ：1 ，1.25和1.5（ kgm 2为单位）
实验测量与约推出,10-15分钟的时间间隔，在此期间，系统冷却到约30-40摄氏度。这使得计算变得很困难，因为确切的该系统的温度分布是不知道的开始测量。然而，可以假定经过一段时间的10-15分钟就足够了一个几乎均一要产生的温度分布。下面的模拟已经选择了一个中间的情况下用转速n=1500转，一轴向力F=4200N 和一个惯量I=1kgm 2。
4 计算两个摩擦过程中所消耗的机械能体被转化成热量
所产生的热量可计算由下列简单的公式：Q =μ·ν·F [W]，其中μ为摩擦系数， v 是滑动速度， F 是垂直压缩表面上的力。和每单位表面的热通量密度q=μ·ν·p [Wm 2]，其中p 是计算的力的比率的压力和的接触表面。作为陶瓷片被放置在两个不同的半径沿离合器盘，所产生的热量必须分别计算每个半径。滑动可分为两部分。在第一部，所述陶瓷侧被保持在一个固定的位置由制动，同时在轴向负荷增大，因此在时间的过程中压缩的变化，而速度双方的差异是恒定的。在第二部分（在同步）的转速差进行均衡,而力值是恒定的，所以在时间的速度变化。基础物所产生的热量是：
nom A t p t v Q 111)()(???=μ nom A t p t v Q 222)()(???=μ
名义接触面积是24的接触表面的聚合和18陶瓷平板电脑在给定的半径。陶瓷小块的直径是:
mm d pellet 16=
计算进行了负荷情况的特点是以下参数:
2
max max 142001500kgm I N F rpm
n ===
基于实验测量的恒定摩擦0.4系数成立。
)(4.0const =μ
速率可以通过速度和半径的知识来计算：
s
m r n v s
m r n v m
r m
r 116028.1460207.0094.02max max 21max max 121=??==??===ππ 表面压力可以计算为轴向力的比率和接触表面。这产生相同的数字的每个陶瓷颗粒，假设即使负载分布。
则有： MPa A A F p nom
nom 496.021max max =+= 这样的话，最大的集中热值就是：
W Q W
Q 7919003619.049000114.014177004825.04960008.144.0max 2max 1=???==???=
在滑动的第一部分，所产生的热上升，由于负载力的增加;在第二部分中，它是减小由于速度差的均衡。这是要知道各滑动部分的时间，以可以指定所产生的热量时间曲线。这些可以是从测量数据序列来确定。同步时间可以很容易地从陶瓷侧的速度来决定。速度的提升是线性的。力的增加是非线性的。为了简单起见，力增加在被取
代的由直线计算使下面的直线的面积近相同的曲线下测量的面积。因此，时间直线的两个端点之间的差异是第一滑动部的时间。
将上述方法应用于每个周期和他们的平均被指定。基于这些结果，下面的值被确定为滑动时间：
应力时间8.2:11=t t s
同步时间92.0:22=t t s
现在发热的时间曲线可以产生。该相同的曲线被用在每一个周期，因为有在每一个循环参数之间没有显著差异。所产生的热量，计算出这种方式，会出现在热模型的热负荷。它必须分布的接触表面通过考虑适当地之间考虑热分区。热分区需要接触的温度是相同的两个表面上。正确的调整需要反复迭代。
传感器技术论文中英文对照资料外文翻译文献
中英文对照资料外文翻译文献 附件1：外文资料翻译译文 传感器新技术的发展 传感器是一种能将物理量、化学量、生物量等转换成电信号的器件。输出信号有不同形式，如电压、电流、频率、脉冲等，能满足信息传输、处理、记录、显示、控制要求，是自动检测系统和自动控制系统中不可缺少的元件。如果把计算机比作大脑，那么传感器则相当于五官，传感器能正确感受被测量并转换成相应输出量，对系统的质量起决定性作用。自动化程度越高，系统对传感器要求越高。在今天的信息时代里，信息产业包括信息采集、传输、处理三部分，即传感技术、通信技术、计算机技术。现代的计算机技术和通信技术由于超大规模集成电路的飞速发展，而已经充分发达后，不仅对传感器的精度、可靠性、响应速度、获取的信息量要求越来越高，还要求其成本低廉且使用方便。显然传统传感器因功能、特性、体积、成本等已难以满足而逐渐被淘汰。世界许多发达国家都在加快对传感器新技术的研究与开发，并且都已取得极大的突破。如今传感器新技术的发展，主要有以下几个方面： 利用物理现象、化学反应、生物效应作为传感器原理，所以研究发现新现象与新效应是传感器技术发展的重要工作，是研究开发新型传感器的基础。日本夏普公司利用超导技术研制成功高温超导磁性传感器，是传感器技术的重大突破，其灵敏度高，仅次于超导量子干涉器件。它的制造工艺远比超导量子干涉器件简单。可用于磁成像技术，有广泛推广价值。 利用抗体和抗原在电极表面上相遇复合时，会引起电极电位的变化，利用这一现象可制出免疫传感器。用这种抗体制成的免疫传感器可对某生物体内是否有这种抗原作检查。如用肝炎病毒抗体可检查某人是否患有肝炎，起到快速、准确作用。美国加州大学巳研制出这类传感器。 传感器材料是传感器技术的重要基础，由于材料科学进步，人们可制造出各种新型传感器。例如用高分子聚合物薄膜制成温度传感器；光导纤维能制成压力、流量、温度、位移等多种传感器；用陶瓷制成压力传感器。
外文文献翻译：汽车的发展
The development of automobile As the world energy crisis and the war and the energy consumption of oil -- and are full of energy in one day someday it will disappear without a trace. Oil is not inresources. So in oil consumption must be clean before finding a replacement. With the development of science and technology the progress of the society people invented the electric car. Electric cars will become the most ideal of transportation. In the development of world each aspect is fruitful especially with the automobile electronic technology and computer and rapid development of the information age. The electronic control technology in the car on a wide range of applications the application of the electronic device cars and electronic technology not only to improve and enhance the quality and the traditional automobile electrical performance but also improve the automobile fuel economy performance reliability and emission spurification. Widely used in automobile electronic products not only reduces the cost and reduce the complexity of the maintenance. From the fuel injection engine ignition devices air control and emission control and fault diagnosis to the body auxiliary devices are generally used in electronic control technology auto development mainly electromechanical integration. Widely used in automotive electronic control ignition system mainly electronic control fuel injection system electronic control ignition system electronic control automatic transmission electronic control ABS/ASR control system electronic control suspension system electronic control power steering system vehicle dynamic control system the airbag systems active belt system electronic control system and the automatic air-conditioning and GPS navigation system etc. With the system response the use function of quick car high reliability guarantees of engine power and reduce fuel consumption and emission regulations meet standards. The car is essential to modern traffic tools. And electric cars bring us infinite joy will give us the physical and mental relaxation. Take for example automatic transmission in road can not on the clutch can achieve automatic shift and engine flameout not so effective improve the driving convenience lighten the fatigue strength. Automatic transmission consists mainly of hydraulic torque converter gear transmission pump hydraulic control system electronic control system and oil cooling system etc. The electronic control of suspension is mainly used to cushion the impact of the body and the road to reduce vibration that car getting smooth-going and stability. When the vehicle in the car when the road uneven road can according to automatically adjust the height. When the car ratio of height low set to gas or oil cylinder filling or oil. If is opposite gas or diarrhea. To ensure and improve the level of driving cars driving stability. Variable force power steering system can significantly change the driver for the work efficiency and the state so widely used in electric cars. VDC to vehicle performance has important function it can according to the need of active braking to change the wheels of the car car motions of state and optimum control performance and increased automobile adhesion controlling and stability. Besides these appear beyond 4WS 4WD electric cars can greatly improve the performance of the value and ascending simultaneously. ABS braking distance is reduced and can keep turning skills effectively improve the stability of the directions simultaneously reduce tyre wear. The airbag appear in large programs protected the driver and passengers safety and greatly reduce automobile in collision of drivers and passengers in the buffer to protect the safety of life. Intelligent electronic technology in the bus to promote safe driving and that the other functions. The realization of automatic driving through various sensors. Except some smart cars equipped with multiple outside sensors can fully perception of information and traffic facilities
机械设计设计外文文献翻译、中英文翻译、外文翻译
机械设计 摘要：机器是由机械装置和其它组件组成的。它是一种用来转换或传递能量的装置，例如：发动机、涡轮机、车辆、起重机、印刷机、洗衣机、照相机和摄影机等。许多原则和设计方法不但适用于机器的设计，也适用于非机器的设计。术语中的“机械装置设计”的含义要比“机械设计”的含义更为广泛一些，机械装置设计包括机械设计。在分析运动及设计结构时，要把产品外型以及以后的保养也要考虑在机械设计中。在机械工程领域中，以及其它工程领域中，所有这些都需要机械设备，比如：开关、凸轮、阀门、船舶以及搅拌机等。 关键词：设计流程设计规则机械设计 设计流程 设计开始之前就要想到机器的实际性，现存的机器需要在耐用性、效率、重量、速度，或者成本上得到改善。新的机器必需具有以前机器所能执行的功能。 在设计的初始阶段，应该允许设计人员充分发挥创造性，不要受到任何约束。即使产生了许多不切实际的想法，也会在设计的早期，即在绘制图纸之前被改正掉。只有这样，才不致于阻断创新的思路。通常,还要提出几套设计方案，然后加以比较。很有可能在这个计划最后决定中,使用了某些不在计划之内的一些设想。 一般的当外型特点和组件部分的尺寸特点分析得透彻时，就可以全面的设计和分析。接着还要客观的分析机器性能的优越性，以及它的安全、重量、耐用性，并且竞争力的成本也要考虑在分析结果之内。每一个至关重要的部分要优化它的比例和尺寸，同时也要保持与其它组成部分相协调。 也要选择原材料和处理原材料的方法。通过力学原理来分析和实现这些重要的特性，如那些静态反应的能量和摩擦力的最佳利用，像动力惯性、加速动力和能量；包括弹性材料的强度、应力和刚度等材料的物理特性，以及流体润滑和驱动器的流体力学。设计的过程是重复和合作的过程，无论是正式或非正式的进行，对设计者来说每个阶段都很重要。 最后，以图样为设计的标准，并建立将来的模型。如果它的测试是符合事先要
车辆工程汽车离合器的外文文献翻译
经典文档下载后可编辑复制 湖北文理学院 毕业设计(论文)英文翻译 题目有限元热分析的陶瓷离合器 专业车辆工程 班级Xxx 姓名Xxxx 学号2010138xx 指导教师 职称Xxx 副教授 2014年2月25日
Fethermal analysis of a ceramic clutch 1. Introduction Abrasive dry running vehicle clutches are force closure couplings. Torque and speed transmission are ensured by the frictional force generated between two pressed surfaces. Reasons for the application of ceramic as a friction medium include good heat and wear resistance properties, which provide the opportunity to drive higher pressures, and a low density. Thus, an increasing power density is enabled with a parallel minimization of construction space. Measurements with a first prototype of a clutch disk using ceramic facings were performed at Karlsruhe University in a laboratory specialized in passenger car drive system testing. In the course of analysis the finite element (FE) model was to be constructed with the knowledge of measurement data and measurement conditions. Calculations were intended to determine the temperature distribution of the clutch disk and its environment at each moment in time corresponding to measurements. It is essential to be familiar with the temperature range in order to examine the wear characteristics of the system. Thus, important information is derived from measurement data. In critical load cases, the highest expected temperatures must be forecast in space and time in order to protect measuring instruments close to the location of heat generation. The goal of this study is to analyze and modify the clutch system to provide better operating conditions by improving the heat conduction and convection of the system or to increase the amount of the energy converted into frictional heat. Furthermore, it is desired to find better design solutions for more efficient clutch systems. Calculations were performed by the Cosmos Design Star software. During model development, great care had to be taken for proper simplification of geometry, the selection of element sizes, and the correct adjustment of time steps due to the substantial hardware requirements for transient calculations. Changes in thermal parameters such as the surface heat convection coefficient and thermal load had to be taken into consideration on an on-going basis in terms of time and location. The two sides of the analyzed test clutch system can only be managed by two independent models linked by heat partition,
无线传感器网络论文中英文资料对照外文翻译
中英文资料对照外文翻译 基于网络共享的无线传感网络设计 摘要：无线传感器网络是近年来的一种新兴发展技术，它在环境监测、农业和公众健康等方面有着广泛的应用。在发展中国家，无线传感器网络技术是一种常用的技术模型。由于无线传感网络的在线监测和高效率的网络传送，使其具有很大的发展前景，然而无线传感网络的发展仍然面临着很大的挑战。其主要挑战包括传感器的可携性、快速性。我们首先讨论了传感器网络的可行性然后描述在解决各种技术性挑战时传感器应产生的便携性。我们还讨论了关于孟加拉国和加利 尼亚州基于无线传感网络的水质的开发和监测。 关键词：无线传感网络、在线监测 1.简介 无线传感器网络，是计算机设备和传感器之间的桥梁，在公共卫生、环境和农业等领域发挥着巨大的作用。一个单一的设备应该有一个处理器，一个无线电和多个传感器。当这些设备在一个领域部署时，传感装置测量这一领域的特殊环境。然后将监测到的数据通过无线电进行传输，再由计算机进行数据分析。这样，无线传感器网络可以对环境中各种变化进行详细的观察。无线传感器网络是能够测量各种现象如在水中的污染物含量，水灌溉流量。比如，最近发生的污染涌流进中国松花江，而松花江又是饮用水的主要来源。通过测定水流量和速度，通过传感器对江水进行实时监测，就能够确定污染桶的数量和流动方向。 不幸的是，人们只是在资源相对丰富这个条件下做文章，无线传感器网络的潜力在很大程度上仍未开发，费用对无线传感器网络是几个主要障碍之一，阻止了其更广阔的发展前景。许多无线传感器网络组件正在趋于便宜化（例如有关计算能力的组件），而传感器本身仍是最昂贵的。正如在在文献[5]中所指出的，成功的技术依赖于
传动系统离合器论文中英文对照资料外文翻译文献
中英文对照资料外文翻译文献 Transmission System A Basic Parts of the transmission system The transmission system applies to the components needed to transfer the drive from the engine to the road wheels. The main components and their purposes are (1) Clutch --- to disengage the drive --- to provide a smooth take-up of the drive (2) Gearbox --- to increase the torque applied to the driving road wheels --- to enable the engine to operate within a given range of speed irrespective of the vehicle speed --- to give reverse motion of the vehicle --- to provide a neutral position so that the engine can run without moving the vehicle (3) Final drive --- to turn the drive through 90° --- to reduce the speed of the drive by a set amount to match the engine to the vehicle (4) Differential --- to allow the inner driving road wheel to rotate slower than the outer wheel when the vehicle is cornering, whilst it ensures that a drive is applied equally to both wheels. B Clutch and Clutch Service In order to transmit the power of the engine to the road wheels of a car, a friction clutch and a change-speed gearbox are normally employed. The former is necessary in order to enable the drive to be taken up gradually and smoothly, while the latter provides different ratios of speed reduction from the engine to the wheels, to suit the particular conditions of running, A clutch performs two tasks: (1) it disengages the engine from the gearbox to allow for gear changing.
外文翻译中文
运作整合 供应链协作的首要问题是提高运作整合的程度。供应链协作课达到的好处，直接关系到捕捉效率之间的职能的企业，以及全国的企业，构成了国内或国际供应链。本章重点阐述的挑战，一体化管理，由研究为什么一体化创造价值，并通过详列的挑战，双方的企业集成和供应链整合。必不可少的供应链流程是确定的。注意的是，然后向信息技术提供，以方便集成化供应链规划。本章最后审查了定价。在最后的分析，定价的做法和政府是至关重要的供应链的连续性。 为什么整合创造价值 基本的优点与挑战的综合管理介绍了在第1章。进一步解释整合管理的重要性，有用的指出客户都至少有三个角度的价值。 传统的角度来看，价值是经济价值。第二个价值的角度来看，是市场价值。 实现双方经济和市场价值是很重要的客户。然而，越来越多的企业认识到商业上的成功也取决于第三个角度来看，价值，被称为关联性。 物流一体化目标 为实现物流一体化的供应链背景下，6个业务目标必须同时取得：（ 1 ）响应，（ 2 ）差额减少，（ 3 ）库存减少，（ 4 ）托运巩固，（ 5 ）质量，（ 6 ）生命周期支持。的相对重要性，每个直接关系到公司的物流战略。 响应 一公司的工作能力，以满足客户的要求，及时被称为反应。作为一再指出，信息技术是促进反应为基础的战略，允许业务的承诺被推迟到最后可能时间，其次是加速投放。实施对应策略服务，以减少库存承诺或部署在预期客户的需求。响应服务转向业务重点从预测未来的需求，以容纳顾客对快速订单到出货的基础上。理想的情况是，在一个负责任的系统中，库存是没有部署，直到客户承诺。支持这样的承诺，公司必须有物流的属性，库存的可用性和及时交付，一旦客户订单收到。 差异减少 所有经营领域的物流系统很容易受到差额。方差结果从未能履行任何预期的层面后勤业务不如预期。举例来说，毫不拖延地在客户订单处理，意想不到的干扰，以便选择，抵港货物损坏，在客户的位置，和/或未能提供在适当的位置上的时间，所有创造无计划的差异，在订单到交货周期。一个共同的解决办法，以保障对不利的差异是使用库存安全库存，以缓冲行动。这亦是共同使用的首选运输，以克服意想不到的差异延误交货计划。这种做法，鉴于其相关的成本高，可以尽量减少使用资讯科技，以维持积极的物流控制。向程度的差异是最小化，物流的生产力将提高。因此，差异减少，消除系统中断，是一个基本的目标，综合物流管理。 库存减少 要达到的目标，库存减少，一个综合物流系统必须控制资产的承诺，并把速度。资产的承诺，是财政的价值部署清单。把速度，反映了利率，这是充实库存随着时间的推移。高转率，再加上预期的库存供货，平均资产用于库存正在迅速而有效利用，这就是整体资产承诺支持一个综合运作减至最低。 库存能够而且确实方便可取的好处这是很重要的要请记住。库存是至关重要的实现规模经济，在制造业和采购。目的是要减少和管理存货，以尽可能最低的水平，同时实现整体供应链绩效的目标。
汽车制动系统(机械、车辆工程毕业论文英文文献及翻译)
Automobile Brake System汽车制动系统 The braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes. Two complete independent braking systems are used on the car. They are the service brake and the parking brake. The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedal or hand lever is set. The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the c ar. The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure). Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.
压力传感器外文翻译
压力传感器 合理进行压力传感器的误差补偿是其应用的关键。压力传感器主要有偏移量误差、灵敏度误差、线性误差和滞后误差，本文将介绍这四种误差产生的机理和对测试结果的影响，同时将介绍为提高测量精度的压力标定方法以及应用实例。 目前市场上传感器种类丰富多样，这使得设计工程师可以选择系统所需的压力传感器。这些传感器既包括最基本的变换器，也包括更为复杂的带有片上电路的高集成度传感器。由于存在这些差异，设计工程师必须尽可能够补偿压力传感器的测量误差，这是保证传感器满足设计和应用要求的重要步骤。在某些情况下，补偿还能提高传感器在应用中的整体性能。 本文以摩托罗拉公司的压力传感器为例，所涉及的概念适用于各种压力传感器的设计应用。 摩托罗拉公司生产的主流压力传感器是一种单片压阻器件，该器件具有 3 类： 1.基本的或未加补偿标定； 2.有标定并进行温度补偿； 3.有标定、补偿和放大。 偏移量、范围标定以及温度补偿均可以通过薄膜电阻网络实现，这种薄膜电阻网络在封装过程中采用激光修正。 该传感器通常与微控制器结合使用，而微控制器的嵌入软件本身建立了传感器数学模型。微控制器读取了输出电压后，通过模数转换器的变换，该模型可以将电压量转换为压力测量值。传感器最简单的数学模型即为传递函数。该模型可在整个标定过程中进行优化，并且模型的成熟度将随标定点的增加而增加。 从计量学的角度看，测量误差具有相当严格的定义：它表征了测量压力与实际压力之间的差异。而通常无法直接得到实际压力，但可以通过采用适当的压力标准加以估计，计量人员通常采用那些精度比被测设备高出至少 10 倍的仪器作为测量标准。 由于未经标定的系统只能使用典型的灵敏度和偏移值将输出电压转换为压 力，测得的压力将产生如图 1 所示的误差。 这种未经标定的初始误差由以下几个部分组成： a.偏移量误差。由于在整个压力范围内垂直偏移保持恒定，因此变换器扩散和激光调节修正的变化将产生偏移量误差。 b.灵敏度误差，产生误差大小与压力成正比。如果设备的灵敏度高于典型值，灵敏度误差将是压力的递增函数（见图 1）。如果灵敏度低于典型值，那么灵敏度误差将是压力的递减函数。该误差的产生原因在于扩散过程的变化。
汽车离合器毕业设计 开题报告
科学技术学院毕业设计开题报告 题目：桑塔纳2000MT轿车膜片弹簧离合器设计 学科部：理工 专业：车辆工程 班级： 081 学号： 7012908022 学生姓名：徐子芬 起讫日期： 2012.2.13—2012.5.4 指导教师：高伟职称：讲师 学科部主任： 审核日期：
一、课题的依据及意义 中国汽车产业经历了57年，特别是改革开放30年的发展，从1999年汽车市场进入以大众消费为基础的成长发展期。由1999年的183.2万辆的市场规模成长为2009年的1364.5万辆，10年来汽车的平均增长率超过20%。在全球金融危机和经济衰退冲击下，全球汽车市场严重萎缩，在此背景下，中国汽车市场2008年仍保持6.8%的增长率，2009年更保持了46.15%的高增长率。与此同时，中国汽车在全球地位已跃入产量和销量均为第一位。中国汽车市场地位已由1999年世界产量排名第9位跃升为2006、2007、2008年连续三年的第3位，市场销量连续三年连续第2位，2009年成为全球汽车产量和销量的都是第一的局面[1]。2010年中国汽车产量和销量分别为1826.47万辆和1806.19万辆，同比分别增长32.44%和32.37%，连续第二年全球第一。我国汽车产量基数已经达到千万辆规模，由于汽车离合器的需求规模和整车产量关系密切，因此我国汽车离合器产品市场增长迅速，2010年我国离合器总销量额将达84亿元，是2005年的2.4倍；其中，盖总成2800万件，从动盘总成5700万件，液力变矩器100万套以上[2]。。 目前全国有汽车离合器生产企业约100多家，其中具有一定生产能力和规模的汽车离合器生产企业只有30多家，主要有：长春一东、湖北三环、杭州西湖、杭州奇碟、桂林福达、东传苏汽配、上海萨克斯、南京法雷奥、重庆爱思帝、珠海华奥、宁波宏协等。近几年，受国内汽车市场的迅猛发展的影响，汽车离合器产量获得快速增长，12家企业离合器总成年产量突破862万套，这些企业基本上都是以配套市场为主[3]。分析原因，主要在于汽车离合器仍是目前国内汽车最为经济、实用的选择，选购经济性车辆的消费者仍占主流。而如今追求享受生活的时代，消费者对车的操控性要求不断提高。自动挡车操作简单，开上它的朋友，刚开始感觉很好，但时间一长，就感觉驾驶自动挡车没什么意思，没有驾驶的乐趣。油价上涨后，用车成本再一次增加。于是人们不得不把目光投向耗油量较小的手动挡车，手动挡车作为市场上的主要车型在爆发力、经济性、驾驶乐趣方面都占有较强的优势。因此离合器在相当长的时期内还是拥有广阔的市场前景。
2019年车辆工程专业毕业论文_外文翻译1.doc
Drive force control of a parallel-series hybrid system Abstract Since each component of a hybrid system has its own limit of performance, the vehicle power depends on the weakest component. So it is necessary to design the balance of the components. The vehicle must be controlled to operate within the performance range of all the components. We designed the specifications of each component backward from the required drive force. In this paper we describe a control method for the motor torque to avoid damage to the battery, when the battery is at a low state of charge. Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved. 1. Introduction In recent years, vehicles with internal combustion engines have increasingly played an important role as a means of transportation, and are contributing much to the development of society. However, vehicle emissions contribute to air pollution and possibly even global warming, which require effective countermeasures. Various developments are being made to reduce these emissions, but no further large improvements can be expected from merely improving the current engines and transmissions. Thus, great expectations are being placed on the development of electric, hybrid and natural gas-driven vehicles. Judging from currently applicable technologies, and the currently installed infrastructure of gasoline stations, inspection and service facilities, the hybrid vehicle, driven by the combination of gasoline engine and electric motor, is considered to be one of the most realistic solutions. Generally speaking, hybrid systems are classified as series or parallel systems. At Toyota, we have developed the Toyota Hybrid System (hereinafter referred to as the THS) by combining the advantages of both systems. In this sense the THS could be classified as a parallel-series type of system. Since the THS constantly optimizes engine operation, emissions are cleaner and better fuel economy can be achieved. During braking, Kinetic energy is recovered by the motor, thereby reducing fuel consumption and subsequent CO 2 emissions. Emissions and fuel economy are greatly improved by using the THS for the power train system. However, the THS incorporates engine, motor, battery and other components, each of which has its own particular capability. In other words, the driving force must be generated within the limits of each respective component. In particular, since the battery output varies greatly depending on its level of charge, the driving force has to be controlled with this in mind. This report clarifies the performance required of the respective THS components based on the driving force necessary for a vehicle. The method of controlling the driving force, both when the battery has high and low charge, is also described. 2. Toyota hybrid system (THS) [1,2] As Fig. 1 shows, the THS is made up of a hybrid transmission, engine and battery. 2.1. Hybrid transmission The transmission consists of motor, generator, power split device and reduction gear. The power split device is a planetary gear. Sun gear, ring gear and planetary carrier are directly connected to generator, motor and engine, respectively. The ring gear is also connected to the reduction gear. Thus, engine power is split into the generator and the driving wheels. With this type of mechanism, the