THE DEVELOPMENT OF A DUCTED WIND TURBINE SIMULATION MODEL
the development of steam power托福阅读
the development of steam power托福阅读
【释义】
the development of steam power
蒸汽动力的发展
【例句】
1With analysis of implement and type selection for steam turbine power supply on LNG ship,the authors forecast the development of new-generation propulsion equipment for LNG ship in future.
作者通过蒸汽轮机动力装置在LNG船上的应用及选型分析，对未来新一代LNG船推进装置的发展趋势进行展望。
2Based on the analysis of two typical turbines(WR-21and GT25000)and other relevant information,the present situation and development trends of naval gas and steam power plants are discussed.
通过二个典型机型(WR-21,GT25000)及其他有关资料的介绍，论述了舰船燃气及蒸汽动力装置的现状与发展趋势。
3With the fast development of the construction in pithead power plant,the large air cooling steam turbine has been widely used in China.
随着我国坑口电站的建设速度加快，大功率空冷机组正成为目前市场的主流产品。
全国版2022版高考英语大一轮复习第三部分高考题型突破题型一阅读理解1备考试题含解析
第三部分高考题型突破题型一阅读理解专题一细节理解题习思用·过关检测Passage 1 ［2020全国Ш，A]语篇类型主题词数难度建议时间应用文文化之旅228 ★4分钟Journey Back in Time with ScholarsClassical Provence（13 days）Journey through the beautiful countryside of Provence， France， with Prof. Ori Z。
Soltes。
We will visit some of the best—preserved Roman monuments in the world。
Our tour also includes a chance to walk in the footsteps of Van Gogh and Gauguin。
Fields of flowers， tile—roofed(瓦屋顶） villages and tasty meals enrich this wonderful experience。
Southern Spain（15 days）Spain has lovely white towns and the scent(芳香）of oranges，but it is also a treasury of ancient remains including the cities left by the Greeks，Romans and Arabs。
As we travel south from Madrid with Prof. Ronald Messier to hist oric Toledo, Roman Mérida and into Andalucia，we explore historical monuments and architecture.China's Sacred Landscapes（21 days）Discover the China of "past ages，" its walled cities, temples and mountain scenery with Prof。
雅思样题1
Only now are technological advances beginning to offer hope that wind power will come to be accepted as a reliable and important source of electricity. There have been significant successes in California, in particular, where wind farms now have a capacity of 1500 megawatts, comparable to a large nuclear or fossil-fuelled power station, and produce 1.5 per cent of the state’s electricity.
The prevailing notion that wind power is too costly results largely from early research which focused on turbines with huge blades that stood hundreds of metres tall. These machines were not designed for ease of production or maintenance, and they were enormously expensive. Because the major factors influencing the overall cost of wind power are the cost of the turbine and its supporting systems, including land, as well as operating and maintenance costs, it is hardly surprising that it was thought at the time that wind energy could not be supplied at a commercially competitive price.
Do Wind Turbines Affect Weather Conditions-
Do WinD Turbines AffecT WeATher conDiTions?Meghan Henschen, BrittanyH errholtz, Lacey Rhudy, Kathryn Demchak (front), Brian Doogs, Joshua H olland, Erik Larson, Johnny Martin (back, pictured left to right), and Matthew Rudkin (not pictured) are seniors in Atmospheric Sciences at Purdue University. Eachmember of the group has a passion for studying weather and l earning the complexities of our atmosphere. The study started as a research project for a class entitled “Atmospheric Measurements and Observations.” They felt the project was a great opportunity and developed an interest for wind energy along the way. In January the group traveled to Seattle, Washington, to present at the 2011 American Meteorological Society Conference. They also won the Student’s Choice Award at the 2011 Under-graduate Research and Poster Symposium in the College of S cience. Meghan Henschen is the primary author and took the lead in the article submission process.Dr. Ki-Hong Min is a v isitinga ssistant professor in theD epartment of Earth and A tmospheric S ciences. Dr. Min’s research interest involves improv-ing the prediction of weather and regional climate with emphasis on s urface-air interactions usingn umerical models and observational data. His current research agenda include improving Purdue R egionalClimate Model (PRCM) and the Weather Research and Forecasting (WRF) model’s s urface representation of cold season and the effect of wind turbines on regional climate. Dr. Min is actively involved in atmospheric science education and c urriculum development, and he enjoys teaching and mentoring u ndergraduate students.AbstractWind turbines are becoming increasingly widespread in the United States as the world looks for cleaner sources of energy. Scientists, policymakers, and citizens have strong opinions regarding the positive and negative effects of wind energy projects, and there is a great deal of misinformation about wind energy circulating on the Web and other media sources. The purpose of this study is to gain a better understanding of how the rotation of hundreds of turbines can influence local weather conditions within a wind farm and in the surrounding areas. This experiment measures temperature, atmospheric pressure, wind speed, wind direction, relative humidity, and evaporation with five weather instruments at Meadow Lake Wind Farm located in White, Jasper, and Benton Counties, Indiana, from November 4 through November 18, 2010. The data show that as wind passes throughout the wind farm, the air warms during the overnight and early morning hours and cools during daytime hours. Observed lower humidity rates and higher evaporation rates downwind also demonstrate that the air dries out as it travels through the wind farm. Further research over multiple seasons is necessary to examine the effects of warmer nighttime temperatures and drier conditions progressively downwind of the installation. Nevertheless, wind turbines did not negatively affect local weather patterns in our small-scale research and may actually prevent frost, which could have important positive implications for farmers by potentially prolonging the growing season.Henschen, M., Demchak, K., Herrholtz, B., Rudkin, M., Rhudy, L., Larson, E., Doogs, B., Holland, J., and J. Martin (2011). Do wind turbines affect weather conditions? A case study in Indiana. Journal of Purdue Undergraduate Research , 1, 22 – 29. doi: 10.5703/jpur.01.1.4Keywordswind turbinesmicro-scale weather Indianarenewable energy agriculturewind energyStudent AuthorsFaculty Mentor22 journal of purdue undergraduate research : volume 1, fall 2011/10.5703/jpur.01.1.4IntroductionWind is a beneficial source of energy for the United States. Unlike fossil fuels, wind energy is clean, efficient, and abundant. Wind projects are springing up acrossthe country, but some individuals and communities are unfamiliar with wind turbine devices and nervous about potential effects. More research is needed to address this uncertainty and minimize local opposition to wind farm proposals. The purpose of this study is to gain a better understanding of how the rotation of hundreds of wind turbines can influence weather conditions immediately within a wind farm and the surrounding areas. More specifically, we hypothesize that the motion of multiple turbines in a cluster will lead to mixing, which will cause isolated air currents, or eddies, to form downwind on the lee side of the site. The mixed air may create warmer nighttime conditions at the site and produce dryer areas downstream of the wind turbines, thus preventing or delaying frost at night and in the early morning. If these theories prove to be accurate, they could make for a longer growing season for farmers whose land lies near the wind farm—a positive, unintentional side effect of an already clean, productive source of energy.how do wind turbines create energy? According to the U.S. Department of Energy, “a wind turbine works the opposite of a fan. Instead of usinge lectricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity” (U.S. Department of Energy, 2010). A wind turbine has three blades that are a erodynamically designed to create a rotating movement as air blows (Roulston, Kaplan, Hardenberg, & Smith, 2003). The basic rotation occurs when the wind blows, causing the blades to create lift, much like the wings of an airplane. The shaft is set at a low speed and will rotate 30 to 60 times per minute. The shaft is then connected to a g earbox that accelerates to 1,000 to 1,800 rotations in a m inute. The high-speed shaft drives a generator to producee lectricity. Finally, the generator is connected to a power plant that stores the electricity and sends it to the grid. Existing research on wind turbines and weather In terms of weather studies, Roy and Pacala (2004)d etermined that as wind moves through the wind t urbines’ r otating propellers, it is mixed with the air above and below, which have different starting conditions (suchas higher or lower temperatures and moisture content). When the two different air types are mixed, the air mass is modified and will either warm or cool and moistenor dry out the original air properties. Furthermore, they state, “Turbulence generated in the wake of the rotors can enhance vertical mixing that significantly affects the v ertical distribution of the temperature and humidity as well as surface sensible and latent heat fluxes” (Roy & Pacala, 2004). In other words, depending on the time of day, rotations from the blades pull warmer or cooler air toward the surface and bring cooler or warmer surface air up, which mixes the air.do Wind turbines affect Weather conditions?: A Case Study in IndianaMeghan Henschen, Kathryn Demchak, Brittany Herrholtz, Matthew Rudkin, Lacey Rhudy, Erik Larson,Brian Doogs, Joshua Holland, and Johnny Martin, Atmospheric SciencesImage 1. The Meadow Lake Wind Farm in Benton County near Fowler, Indiana, contains over 300 wind turbines(image courtesy of Erica A. Morin).do wind turbines affect weather conditions? 23Data reviewed by Roy and Traiteur (2010) suggest that, “near-surface air temperatures downwind of the wind farm are higher than upwind regions during night and early morning hours, whereas the reverse holds true for the rest of the day.” Many wind farms are built overa gricultural land, so the turbines can actually have beneficial effects, such as the nocturnal warming of ambient air to protect crops from frost. This causes a pressure gradient to flow from warmer east air to the cooler west air, resulting in surface radiation cooling of the ground and in a drier climate that is strongest in the early morning hours and decreases throughout the day (Roy & Traiteur, 2003).Experiment procedures and site description We chose to conduct this experiment at the Meadow Lake Wind Farm in White, Jasper, and Benton Counties, I ndiana. This large wind energy project is a pproximately 30 miles northwest of the campus of Purdue University. The entire Meadow Lake site consists of 121 Vestas V82 1.65 MW wind turbines, 66 Acciona AWs 1.5 MW —turbines, 69 model sle GE 1.5 MW turbines, and 47 Suzlon S88 2.1 MW turbines, for a combined total of over 300 turbines. In coming years, Horizon Wind Energy C ompany will i nstall Phase V and VI for an estimatedt otal of around 600 turbines and nameplate capacity of nearly 1,000 MW once the entire project is online (Horizon Wind Energy, 2011). These turbines are a rranged in a cluster pattern and range from approximately 135 feet tall to 380 feet tall, thereby creating a significant distance between the blade rotation and ground area.For this experiment, the weather equipment used to c ollect the data consisted of four WXT-510 weather i nstruments that measure different surface parameters, one MAWS101 weather station to measure surface conditions, and three evaporation containers. The weather equipment was set up in diverse spots in Benton County, Indiana, and arranged in a square formation with all of the weather instruments approximately equal distances apart. There was a WXT-510 at each of the four corners of the square, with the MAWS101 located in the center of the square. P arameters measured for this experiment were temperature, airp ressure, wind speed, wind direction, relative humidity, and rainfall amount.The MAWS101 weather station was positioned in the center of the designated research area, approximately 4,500 meters away from each corner site, in a cornfield and away from roads and houses. The MAWS101 was set up near a few wind turbines in order to collect potential data supporting the hypothesis that wind turbines affect the temperatures and moisture within the wind farm (see Figure 1).Each site had technical problems collecting data due to laptop computer errors, but data were successfullyc ollected by the weather instruments for 13 days starting from November 4 to November 18, 2010. Each instrument was set to retrieve data every two minutes for each day. Data were collected from November 4 to November 11 for the MAWS and northeast sites and, after obtaining new laptop computers, the MAWS, southwest, northwest, and northeast sites were able to retrieve data from November 11 to November 17.The evaporation containers were put out at the MAWS, northwest, and northeast sites on November 5. Thee vaporation containers were filled with water andm easured upon initial placement at the sites, again on November 11, and at the terminus of data collection. M easurements a ccounted for the amount of precipitation that fell during the experiment time. Rainfall at the sites was recorded daily and added into the containers’ total amount while winds were averaged each day to create an “average wind direction” for the day.Temperature and relative humidity results From approximately November 4 to November 6, winds were out of the northwest. Pressure steadily increased throughout these days, and by the end of November 5, the relative humidity was nearing 90 percent. From nightfall until approximately mid-morning on November 6, a short-wave warm front came through that switched the winddirection from northwest to south. When the warm frontFigure 1. This map shows the experiment site in BentonC ounty. The red dots represent the location of weatheri nstruments, and the blue dots represent each wind turbine.24 journal of purdue undergraduate research : volume 1, fall 2011Figure 2 and Figure 3. These graphs show the temperature and relative humidity for the MAWS and northeast site from November 4 through November 12, 2010. The arrows indicate that the southwest and northwest winds had greater nightly temperature and relative humidity differences.Figure 4. Conditions at the MAWS and northeast sites at 8:50 a.m. on November 5, 2010. Wind from the northwest is i ndicated by the red arrows. The text boxes contain the t emperature and relative humidity at the two sites.Figure 5. Conditions at the MAWS and northeast sites at7:30 a.m. on November 8, 2010. Wind from the southwest is i ndicated by the red arrows. The text boxes contain thetemperature and relative humidity at the two sites.do wind turbines affect weather conditions ? 25passed, air pressure was steady for roughly two days, and relative humidity dropped to 60 percent during d aytime hours. Another front passed through on N ovember 10, shifting winds to the south for the remainder of thep eriod. Figures 2 and 3 show the temperature and relative humidity in this period.From November 4 through November 11, significant nighttime differences were observed in temperature and relative humidity under the southwest flow. At most other times, the temperature and relative h umidity remained fairly consistent between the two sites due to wind d irection. In particular, the nighttime mixing was most prevalent for two days during the experiment period. The first of these days was November 5, with o bservation o ccurring at 8:50 a.m. (see Figure 4). On thism orning, Benton County experienced a northwest wind. The MAWS recorded a temperature of 32.3°F, and then ortheast site recorded 32.7°F. At this point, the wind direction was nearly perpendicular to the plane of the two sites, and it is safe to assume that the mixing was nearly identical. The MAWS did, however, record a r elative humidity of 86 percent while the northeast site onlyrecorded 79 percent. Throughout the experiment, though, the MAWS consistently recorded higher relative humidity than the other WXT instruments had recorded throughout the duration of the experiment, which suggests a bias in the instrument data. With this said, the two sites weree ssentially experiencing the same atmospheric environ-ment on that particular morning.Figure 6 and Figure 7. These graphs show the temperature and relative humidity for the MAWS, southwest site, northwest site, and northeast site from November 11 through November 18, 2010. The arrows indicate that the southeast and southwest winds resulted in the greatest temperature and relative humidity differences.The next date analyzed was November 8, 2010, with observation at 7:30 a.m. (see Figure 5). On this m orning, the site location had southwest winds. This flow was favorable to our research because we could compare the surface variables at a site in the center of the wind farm—under the mixing influence of the southwest portion of the wind farm—and a site at the northeast corner of the wind farm. The MAWS recorded a temperature of 36.3°F, and the northeast site recorded a temperature of 41.2°F. Since these two sites are only about 4,500 meters apart, this is a significant temperature difference. There was obvious mixing at the surface due to the wind turbines. Again, we noted that the MAWS recorded higher relative humidity, but at this time the MAWS recorded 68 percent relative humidity, and the northeast site recorded 54 percent. Accounting for the higher relative humidity bias in the MAWS, the relative humidity difference became much greater during the southwest flow, suggesting that these results were due to the bias plus the mixing. These results were significant because they indicated that mixing also reduced relative humidity throughout the wind farm.From November 11 to November 17, all sites except the southeast site were able to be analyzed. The placement of functioning weather instruments in this period was more ideal, because they covered more ground within the wind farm and provided better spatial results. Starting onN ovember 13, winds changed from southeast to south -west, with wind speeds increasing at each site as winds shifted westward. The pressure dropped dramatically26 journal of purdue undergraduate research : volume 1, fall 2011Figure 8. Conditions at the southwest, northwest, northeast, and MAWS sites at 4:40 a.m. on November 13, 2010. Wind from the southeast is indicated by the red arrows. The text boxes list the temperature and relative humidity at the four sites.Figure 9. Conditions at the southwest, northwest, northeast, and MAWS sites at 12:30 a.m. on November 15, 2010. Wind from the south-southwest is indicated by the red arrows. The text boxes list the temperature and relative humidity at the four sites.Figure 10. Air begins to dry out as it travels from the southwest to the northeast in the wind farm.from November 12 to November 13, and then became steady until November 15 at 8:00 p.m.. Winds also shifted dramatically during this time. Southwest winds became southerly, and then shifted to easterly by November 16. On November 18, winds were blowing from the north in the morning and from the west by midday. This was indicative of a cyclonic flow due to a low pressure s ystem. During this time frame, the air pressure dropped from about 984 hPa to 973 hPa. Figures 6 and 7 show thet emperature and relative humidity in this period. According to the data collected from November 11 to N ovember 18, temperature and relative humidityd ifferences were less obvious between the four sitesd uring this period and the two sites from the previous period. The most significant nighttime differences were associated with a southwest flow, and we observed two additional dates and times in which the nighttime m ixing was most prevalent. The first date was November 13 at 4:40 a.m. (see Figure 8). This wind pattern was not ideal for gathering information, given the placement of the instruments. With the southeast WXT-510 not c ollecting data, the northeast and southwest WXT-510 and MAWS were positioned almost perpendicular to the windd irection. This scenario provided our research team with less opportunity to determine temperature and relative humidity variation before and after the wind mixing with the turbines. The three functioning weather instruments received wind simultaneously and therefore exhibited roughly the same temperature and relative humiditydo wind turbines affect weather conditions ? 27readings. The southwest site recorded a t emperature of 52.9°F and r elative humidity of 49 percent; the MAWS recorded 53.3°F and 49 percent relative humidity; and the northeast site recorded 51.3°F and 51 percent r elative humidity. These were all fairly consistent with only slight variations. The MAWS captured the warmest of the three t emperatures, which was also the farthest n orthwest.To further the results, the northwest site recorded at emperature of 53.6°F and a relative humidity of 46p ercent. Even though this site was not within the bounds of the wind farm, this is the highest temperature andl owest relative humidity of the four sites. This implies that wind turbine mixing extends outside the bounds of the wind farm and into the surrounding land.The second date was November 15 at 12:30 a.m. (see Figure 9). Winds from the south-southwest provided ideal conditions at that time. The southwest site recorded at emperature of 34.7°F and relative humidity of 66 p ercent; the northwest site recorded a temperature of 38.7°F and relative humidity of 56 percent; the MAWS recorded 36.6°F and 65 percent relative humidity; and the north-east site recorded 39°F and 55 percent relative humidity. One can see that the southwest portion of the wind farm had the lowest temperature, while the northern portionof the wind farm had the highest temperatures. From the southwest site to the northeast site, temperatures varied by 4.3°F and relative humidity varied by 11 percent. These are significant differences given the close proximity of these two sites.Evaporation resultsEvaporation containers were placed at three sites: the northwest site, the northeast site, and the central MAWS site. Rainfall at these sites was recorded daily and added into the containers’ total amount, while winds were a veraged each day to create an “average windd irection” for the day. Our results demonstrated that relative h umidity decreased and evaporation increasedp rogressively downwind of the wind farm.At the time of initial container placement and up until the first observation, winds came out of the southwest57 p ercent of the time, the north seven percent of the time, and the south 29 percent of the time. During the second half of the observation period, winds came outof the southwest most frequently, 57 percent of the time. South winds prevailed 14 percent of the time and south-west winds another 14 percent. Looking at winds for theentire period, it is clear that southwest winds were the Figure 11. Increases in temperature and relative h umidity in the areas surrounding wind farms may prevent frost and i ncrease the growing season for local farmers (image c ourtesy of Erica A. Morin).28 journal of purdue undergraduate research: volume 1, fall 2011most common, occurring 54 percent of the time. Other wind directions included north at eight percent, south at 23 p ercent, and northwest at 15 percent of the time. With winds out of the southwest more than 50 percent of the time, we expected more evaporation would occur from southwest to northeast. In other words, the air should have been getting drier as it traveled through the wind farm (see Figure 10).Evaporation amounts throughout the study show that the northeast site had the most evaporation, with a total of 3.2 mm. The MAWS site had evaporation totals of 1.4 mm, and the northwest site had 1.5 mm of evaporation. The northeast site had 52 percent more evaporation then the MAWS site, which further verifies the results of the study. These results coincide with the relative humidity findings of conditions becoming drier as winds blow through the wind farm.ConclusionWe found that the constellations of wind turbines in a wind farm impact local climate conditions in and around the wind farm. The results of this study show that as air travels through the wind farm, it is “churned” by the wind turbine propellers, which causes the air at a higher elevation to mix with air at the surface. The data show that the air warms consistently as it mixes throughout the wind farm during overnight and early morning hours.In addition to warming, the air that travels through the wind farm also dries out. The data showed lower relative h umidity and higher evaporation where the wind exited the wind farm. Since the air is warming and drying out as it passes through the wind farm, this could potentially prevent frost within the vicinity of the establishment. These effects have positive implications for farmers in the area, as the prevention of frost may help create a longer growing season for crops.These results show evidence that wind turbines do affect micro-scale weather variables, but it would bea ppropriate for this study to be reexamined with a l onger e xperimental period through multiple seasons. Ana dditional parameter, such as soil moisture, should also be analyzed to determine differences in soil moisture at wind turbine sites and its possible impact on crops. A study over multiple months would also help reinforce the theory of wind turbine impacts on local climate, as well as help to better distinguish atmospheric variables.AcknowledgmentsThis research is supported by the College of Science Instructional Equipment Grant. The authors would like to thank editorial members for improving this manuscript and the farmland owners for allowing access to their properties.ReferencesHorizon Wind Energy. (2011). Meadow Lake Wind Farm.R etrieved April 28, 2011, from http://www. Roulston, M. S., Kaplan, D. T., Hardenberg, J., & Smith, L. A. (2003). Using medium-range weather forecasts to improve the value of wind energy production. Renewable Energy, 28(4), 585-602.Roy, S. B., & Pacala, S. W. (2004). Can large wind farmsa ffect local meteorology? Journal of Geophysical Research, 109, D19101.Roy, S. B., & Traiteur, J. J. (2010). Impacts of wind farms on surface air temperatures. PNAS, 107(42), 17899-17904. U.S. Department of Energy. (2010). How Wind Turbines Work. Retrieved April 28, 2011, from Find out more about Dr. Ki-Hong Min’sresearch in the Department of Earth andAtmospheric Sciences:/pup/mindo wind turbines affect weather conditions? 29。
地理大发现英文
地理大发现英文The Great Geographical DiscoveriesThe period known as the Great Geographical Discoveries refers to the era between the 15th and 17th centuries when European explorers embarked on groundbreaking voyages that expanded the known boundaries of the world. These intrepid adventurers ventured into unknown territories, charting new maps, establishing colonies, and bringing back valuable resources from distant lands. These discoveries forever changed the course of history and shaped our modern understanding of geography.One of the most significant figures of this era was Christopher Columbus. In 1492, under the sponsorship of the Spanish Crown, Columbus set sail with the intention of finding a new sea route to Asia. Instead, he stumbled upon the Americas, completely unaware of the major impact it would have on the world. This accidental encounter opened up a new world to European explorers and led to the eventual colonization of the Americas.Another noteworthy explorer of this period was Ferdinand Magellan. In 1519, Magellan embarked on a voyage to find a western route to the Spice Islands, located in modern-day Indonesia. His expedition, which included the first circumnavigation of the globe, proved that the Earth was round and significantly expanded our understanding of its size and shape.The Portuguese explorer Vasco da Gama is also recognized for his monumental achievements during this period. In 1497, da Gama became the first European to reach India by sea, establishing a direct trade route between Europe and the Indian subcontinent. This discovery greatly impacted global trade and solidified Portugal's status as a major maritime power.These discoveries not only reshaped the maps of the world but also led to far-reaching consequences. The colonization and exploitation of the newly discovered lands led to the tragic displacement and annihilation of indigenous populations, as well as thetransatlantic slave trade. The Great Geographical Discoveries also sparked an era of exploration and colonization, with European powers vying for territorial influence and resources across the globe.Furthermore, these voyages of discovery brought about a significant exchange of goods, ideas, and cultures between different continents. The Columbian Exchange, named after Christopher Columbus, describes the widespread transfer of plants, animals, and diseases between the Eastern and Western Hemispheres. This exchange had profound effects on both ecosystems and societies, as new crops were introduced, population demographics shifted, and diseases wreaked havoc on previously isolated populations.In conclusion, the Great Geographical Discoveries of the 15th to 17th centuries were pivotal moments in history. They not only expanded our knowledge of the world but also reshaped economic systems, altered power dynamics, and brought about immense cultural exchanges. Although these discoveries had both positive and negative consequences, their impact on the course of human history cannot be overstated. The explorations of Christopher Columbus, Ferdinand Magellan, and Vasco da Gama forever changed our understanding of geography and set the stage for the globalization that we see today.。
a wind turbine作文
a wind turbine作文Wind turbines are a form of renewable energy technology that harnesses the power of the wind to generate electricity. These towering structures, with their large spinning blades, are a common sight in many countries around the world. Wind turbines are an important part of the transition to more sustainable and environmentally-friendly energy sources.风力涡轮机是一种利用风力发电的可再生能源技术。
这些高耸的结构和旋转的大叶片在世界许多国家都是常见的景观。
风力涡轮机是向更可持续和环保的能源来源过渡的重要组成部分。
One of the key benefits of wind turbines is that they produce electricity without emitting greenhouse gases or other pollutants. This is in stark contrast to traditional fossil fuel power plants, which contribute significantly to air pollution and climate change. By generating clean energy from the wind, wind turbines play a crucial role in reducing carbon emissions and combating global warming.风力涡轮机的一个关键好处是它们在不排放温室气体或其他污染物的情况下产生电力。
11.8号托福阅读真题答案解析
11.8号托福阅读真题答案解析本文关于2017年11月18日阅读真题回忆，有利于考生备考复习。
让我们回忆一下最近考试的内容：环境类，生物类，词汇题等，请考生们要认真的阅读哦，来店铺会给你不一样的精彩内容，店铺会在考试后第一时间更新。
11.8号托福阅读答案解析阅读部分考试回忆如下：1. Preventing Overgrowth among Tree Branchesshedding剪枝的意义。
一个是因为有些树枝消耗掉的碳物质比生产的多，另一个原因是有时候气候很干，剪枝减少水的消耗。
词汇题补充：exposed = unprotectedwith no warning = without any indication beforehandcongestion = overcrowding2. Crown of Thorns Starfish and Coral Reefs冠状棘海星，话题重复2011.01.08珊瑚的消失和一种海星的数量猛增有关系，主要说的是导致猛增的原因(环境+人)词汇题补充：outbreak = sudden increaseaccompany = occur along withconverge = come togetherseverity = seriousness原题重现：The crown of thorns starfish, Acanthaster Tlanci, is large, twenty-five to thirty-five centimeters in diameter, and has seven to twenty-one arms that are covered in spines. It feeds primarily on coral and is found from the Indian Ocean to the west coast of Central America, usually at quite low population densities. Sincethe mid-1950s, population outbreaks at densities four to six times greater than normal have occurred at the same time in places such as Hawaii, Tahiti, Panama, and the Great Barrier Reef. The result has often been the loss of a fifty percent to nearly one hundred percent of the coral cover over large areas.A single Acanthaster can consume five to six square meters of coral polyps per year, and dense populations can destroy up to six square kilometers per year and move on rapidly. Acanthasters show a preference for branching corals, especially Acroporids. After an outbreak in a particular area, it is common to find that Acroporids have been selectively removed, leaving a mosaic of living and dead corals. In places where Acroporids previously dominated the community devastation can be almost complete, and local areas of reefs have collapsed.Areas of dead coral are usually colonized rapidly by algae and often are later colonized by sponges and soft corals. Increases in abundance of plant-eating fish and decreases in abundance of coral-feeding fish accompany these changes. Coral larvae settle among the algae and eventually establish flourishing coral colonies. In ten to fifteen years the reefs often return to about the same percentage of coral cover as before. Development of a four-species diversity takes about twenty years.Two schools of thought exist concerning the cause of these outbreaks. One group holds that they are natural phenomena that have occurred many times in the past, citing old men's recollections of earlier outbreaks and evidence from traditional cultures. The other group maintains that recent human activities ranging from physical coral destruction through pollution to predator removal have triggered these events.One theory, the adult aggregation hypothesis, maintains thatmost species is more abundant than we realize when a storm destroys coral and causes a food shortage. The adult Acanthasters converge on remaining portions of healthy coral and feed hungrily. Certainly there have been outbreaks of Acanthaster following large storms, but there is little evidence that the storms have caused the enough reef damage to create a food shortage for these starfish.Two other hypotheses attempt to explain the increased abundance of Acanthaster after episodes of high terrestrial runoff following storms. The first hypothesis is that low salinity and high temperatures favor the survival of the starfish larvae. The second hypothesis emphasizes the food web aspect, suggesting that strong fresh water runoff brings additional nutrients to the coastal waters, stimulating phytoplankton production and promoting more rapid development and better survival of the starfish larvae.Those favoring anthropogenic (human influenced) causes have pointed to the large proportion of outbreaks that have been near centers of human populations. It has been suggested that coral polyps are the main predators of the starfish larvae. Destruction of coral by blasting and other bad land use practices would reduce predation on the starfish larvae and cause a feedback in which increases in Acanthaster populations cause still further coral destruction. Unfortunately, there are too few documented instances of physical destruction of coral being followed by outbreaks of Acanthaster for these hypotheses to be fully supported.Another group of hypothesis focuses on removal of Acanthaster's predators. Some have suggested that the predators might have been killed off by pollution whereas othershave suggested that the harvesting of vertebrate and invertebrate predators of Acanthaster could have reduced mortality and caused increased abundance of adults. The problem with this group of hypothesis is that it is difficult to understand how reduced predation would lead to sudden increases in Acanthaster numbers in several places at the same time in specific years. It seems probable that there is no single explanation but that there are elements of the truth in several of the hypotheses. That is there are natural processes that have led to outbreaks in the past, but human impact has increased the frequency and severity of the outbreaks.3.Dorset Culture格林兰岛Dorset Culture的起源，首先是由于气候变冷，一部分人迁走了，另一部分留下来的人创立了文明。
于对区爱美学校高考英语阅读理解抓分训练__2
于对区爱美学校2014高考英语阅读理解抓分训练（57）及答案阅读理解There’s an energy crisis in America, and it has nothing to do with fossil fuels. Millions of us get up each morning already weary over the day holds. “I just can’t get started.” People say. But it’s not physical energy that most of us lack. Sure, we could all use extra sleep and a better diet. But in truth, people are healthier today than at any time in history. I can almost guarantee that if you long for more energy, the problem is not with your body.What you’re seeking is not physical energy. It’s emotional energy. Yet, sad to say life sometimes seems designed to exhaust our supply. We work too hard. We have family obligations (义务). We encounter (遭遇) emergencies and personal crises. No wonder so many of us suffer from emotional fatigue (疲劳), a kind of utter exhaustion of the spirit.And yet we all know people who are filled with joy, despite the unpleasant circumstances of their lives. Even as a child I observed people who were poor or disabled or ill, but who nevertheless faced life with optimism and vigor (活力). Consider Laura Hillenbrand, who despitean extremely weak body wrote the best-seller Seabiscuit. Hillenbrand barely had enough physical energy to drag herself out of bed to write. But she was fueled by having a story she wanted to share. It was emotional energy that helped her succeed. Unlike physical energy, which is finite (有限的) and diminishes (减少) with age, emotional energy is unlimited and has nothing to do with genes or upbringing. So how do you get it? You can’t simply tell yourself to be positive. You must take action. Here are six practical strategies that work.1. Do something new.Very little that’s new occurs in our lives. The impact of this sameness on our emotional energy is gradual, but huge: It’s l ike a tire(轮胎) with a slow leak（漏）. You don’t notice it at first, but eventually you’ll get a flat. It’s up to you to plug the leak—even though there are always a dozen reasons to stay stuck in your dull routines of life. That’s where Maura, 36, a waitress, found herself a year ago. Fortunately, Maura had a lifeline—a group of women friends who meetregularly to discuss their lives. Their lively discussions spurred Maura to make small but nevertheless life altering changes. She joined a gym in the next town. She changed her look with ashort haircut and new black T-shirts. Eventually, Maura gathered the courage to quit her job and start her own business. Here’s a challenge: If it’s something you wouldn’t ordinarily do, do it. Trya dish you’ve never eaten.Listen to music you’d ordinarily tune out. You’ll discover these small things add to your emotional energy.2. Reclaim life’s meaning.So many of my patients tell me that their lives used to have meaning, but that somewhere along the line things went stale (厌倦的). The first step in solving this meaning shortage is to figure out what you really care about, and then do something about it. A case in point is Ivy, 57, a pioneer in investment banking. “I mistakenly believed that all the money I made would me an something.” she says. “But I feel lost, like a 22-year-old wondering what to do with her life.” Ivy’s solution? She started a program that shows Wall Streeters how to donate time and money to poor children. In the process, Ivy filled her life with meaning.3. Put yourself in the fun zone.Most of us grown-ups are seriously fun-deprived（缺乏的）. High-energy people have the same day-to-day work as the rest of us, but they manage to find something enjoyable in every situation.A real estate broker I know keeps herself amused on the job by mentally redecorating the houses she shows to clients（客户）. “I love imagining what even the most run-down house could look like with a little tender loving care,” she says. “It’s a challenge—and the least desirable properties a re usually the most fun.” We all define fun differently, of course, but I can guarantee this: If you put just a bit of it into your day, you energy will increase quickly4. Bid farewell （告别）to guilt and regret.Everyone’s past is filled with regrets that s till cause pain. But from an emotional energy point of view, they are dead weights that keep us from moving forward. While they can’t merely be willed away, I do recommend you remind yourself that whatever happened in the past, nothing can change that. Holding on to the memory only allows the damage to continue into the present.5. Make up your mind]Say you’ve been thinking about cutting your hair short. Will it look stylish—or too extreme? You endlessly think it over. Having the decision hanging over your head is a huge energy drain. Every time you can’t decide, you burden yourself with alternatives. Quit thinking that you have to make the right decision; instead, make a choice and don’t look back.6. Give to get.Emotional energy has a kind of magical quality: the more you give, the more you get back. This is the difference between emotional and physical energy with the latter. You have to get it to be able to give it. With the former, however, you get it by giving it. Start by asking everyoneyou meet, “How are you?” as if you really want to know, and then listen to the reply. Be the one who hears. Most of us also need to smile more often. If you don’t smile at the person you love first thing in the morning, you’re sucking energy out of your relationship. Finally, help another person—and make the help real, concrete. Give a massage to someone you love, or cook her dinner, then, expand the circle to work. Try asking yourself what you’d do if your goal were to be helpful rather than efficient. After all, if i t’s true that what goes around comes around, why not make sure that what’s circulating around you is the good stuff?16. Laura Hillenbrand is an example quoted to show how ________ in life.A. physical energy can contribute to one’s unsuccessB. emotional energy can contribute to one’s successC. physical energy can contribute to one’s successD. emotional energy can contribute to one’s unsuccess17. The author believes emotional energy is ________.A. inherited and genetically determinedB. related to inherited and genesC. not inherited and genetically determinedD. related to inherited and upbringing18. Even small changes people make in their lives ________ their emotional energy.A. cannot help controlB. cannot help increaseC. can help controlD. can help increase19. Ivy filled her life with meaning by launching a program to ________.A. help herselfB. teach herselfC. teach poor childrenD. help poor children20. The real-estate broker the author knows enjoyed ________.A. redecorating the housesB. mentally redecorating the housesC. the same day-to-day workD. defining fun differently参考答案 BCDDB(2011·江苏卷，C) According to the US government, wind farms off the Pacific coast could produce 900 gigawatts of electricity every year.Unfortunately，the water there is far too deep for even the tallest windmills(see picture)to touch bottom. An experiment under way off the coast of Norway，however，could help put them anywhere.The project, called Hywind，is the world's first largescale deepwater wind turbine(涡轮发电机)．Although it uses a fairly standard 152ton,2.3megawatt turbine，Hywind represents totally new technology. The turbine will be fixed 213 feet above the water on a floating spar(see picture)，a technology Hywind's creator，the Norwegian company StatoilHydro，has developed recently. The steel spar, which is filled with stones and goes 328 feet below the sea surface, will be tied to the ocean floor by three cables(缆索)；these will keep the spar stable and prevent the turbine from moving up and down in the waves.Hywind's stability(稳定性)in the cold and rough sea would prove that even the deepest corners of the ocean are suitable for wind power. If all goes according to plan, the turbine will start producing electricity six miles off the coast of southwestern Norway as early as September.To produce electricity on a large scale, a commercial wind farm will have to use bigger turbines than Hywind does, but it's difficult enough to balance such a large turbine so high on a floating spar in the middle of the ocean. To make that turbine heavier, the whole spar's centre of gravity must be moved much closer to the ocean's surface. To do that, the company plans to design a new kind of wind turbine, one whose gearbox(变速箱) sits at sea level rather than behind the blades(see picture)．Hywind is a test run, but the benefits for perfecting floating windfarm technology could be extremely large. Out at sea, the wind is often stronger and steadier than close to shore, where all existing off shore windmills are planted. Deepsea farms are invisible from land, which helps overcome the windmillaseyesore objection. If the technology catches on, it will open up vast areas of the planet's surface to one of the best lowcarbon power sources available.本文为科普短文，讲述世界上第一个深海风力发电机——涡轮发电机以及它的发电原理及好处。
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1.6
2 3 3
Cv δ 3 / 2
(5)
Variation of Cp with
δ
(1)
1.4 1.2 1
Differentiating Equation 1 with respect to U2 gives the maximum power condition:
THE DWT MODEL
The model described here has been derived from a design (figure 1) that attaches to the roof edge of rectangular-section buildings, making use of the pressure differentials that are naturally created by the action of the wind. To illustrate the potential for power production from such a device, a simple, validated mathematical model has been constructed for one-dimensional flow (Grant et al. 2002). This is shown in Figure 2.
ABSTRACT
Embedded generation has been described as a “paradigm shift” in the way in which electricity is produced, with the focus of power production shifting away from large centralised generation plants to production of heat and power close to the point of use. An emerging technology that may play a part in the evolution of this new paradigm is the ducted wind turbine (DWT). Up to this point, wind energy has not played a major role in embedded generation for the built environment. However, the development of these small micro turbines that can be integrated into the building fabric, opens up the possibility of utilising the differential pressures that occur due to airflow around buildings for the purpose of local power production. This paper describes recent work to develop and test a simple mathematical model of a Ducted Wind Turbine and its integration within the various technical domains of a building simulation tool. Specifically, the paper will describe: a) the concept of the ducted wind turbine; b) the development of the mathematical model; c) the integration of the model into a building simulation tool. The paper will conclude with a case study in which the simulation model will be used to analyse of the likely power output from a building design incorporating ducted wind turbines within the facade. Keywords: ducted wind turbine, mathematical model, embedded generation, building simulation.
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The power output of the component is therefore a function of the duct velocity coefficient (Cv), the opening area A and the free stream velocity of the wind, U ∞ . Experimental analysis (Grant et al. 2002) has shown Cv to be close to 1.0 Equation 3 can be re-arranged to give the power output in terms of a power coefficient CP and the available power in the wind Pw, which is defined as:
Pw =
1 3 ρ AU ∞ 2
(4)
By inspection of Equation 3 the power coefficient is:
Cp =
Figure 1 a picture of a DWT. Analysis of this model shows that the power extracted from the air stream is:
INTRODUCTION
As we move into the 21st century technological innovation is changing the means by which heat and power can be delivered to the built environment. New “micro-grid” type technologies offer the potential of supplying heat and power locally from “clean” and energy- efficient-type technologies. Examples of these technologies include micro-CHP
Eighth International IBPSA Conference
Eindhoven, Netherlands August 11-14, 2003
THE DEVELOPMENT OF A DUCTED WIND TURBINE SIMULATION MODEL Andy Grant, Nick Kelly Energy Systems Research Unit, University of Strathclyde, Scotland e-mail: andy@, nick@ Tel: +44 (0)141 548 3986 Fax: +44 (0)141 552 5105
using Stirling engines, photovoltaics (PV) and fuel cells. To assess the effectiveness of these devices and also to assess the impact of their diffusion into the built environment it is necessary to develop models to simulate their performance in a realistic operational context. Building simulation offers a means to do this and can reveal important performance characteristics such as the total energy yield, the temporal characteristics of heat and power output and their compatibility with the loads that they are designed to serve. The ducted wind turbine (DWT) (Webster, 1979) is an emerging micro-grid technology; this is a small, wind energy conversion device that can be integrated into the façade of a building and may be a useful means of producing power in areas with windier climates. The ducted wind turbine overcomes many of the problems associated with the use of conventional wind turbines in an urban environment, which are hampered by high levels of turbulence in the air stream, and are also constrained by concerns over visual impact, noise and public safety. In contrast DWT units are purposely designed for attachment to buildings and are both robust and unobtrusive. This paper describes the integration of a simple DWT model (Grant et al. 2002) into a building simulation tool.