毕业设计水利水电工程英文文献翻译
水利水电工程毕业设计英文翻译,混凝土重力坝
Concrete Gravity DamThe type of dam selected for a site depends principally on topographic, geologic,hydrologic, and climatic conditions. Where more than one type can be built, alternative economic estimates are prepared and selection is based on economica considerations.Safety and performance are primary requirements, but construction time and materials often affect economic comparisons.Dam ClassificationDams are classified according to construction materials such as concrete or earth. Concrete dams are further classified as gravity, arch, buttress, or a combination of these. Earthfill dams are gravity dams built of either earth or rock materials, with particular provisions for spillways and seepage control.A concrete gravity dam depends on its own weight for structural stability. The dam may be straight or slightly curved, with the water load transmitted through the dam to the foundation material. Ordinarily, gravity dams have a base width of 0.7 to 0.9 the height of the dam. Solid rock provides the best foundation condition. However, many small concrete dams are built on previous or soft foundations and perform satisfactorily. A concrete gravity dam is well suited for use with an overflow spillway crest. Because of this advantage, it is often combined with an earthfill dam in wide flood plain sites.Arch dams are well suited to narrow V- or U-shaped canyons. Canyon walls must be of rock suitable for carrying the transmitted water load to the sides of the canyon by arch action. Arch sections carry the greatest part of the load; vertical elements carry sufficient load through cantilever action to produce cantilever deflections equal to arch deflections. Ordinarily, the crest length-to-height ratio should be less than 5, although greater ratios have been used. Generally, the base width of modern arch dams is 0.1 to 0.3 the height of the impounded water. A spillway may be designed into the crest of an arch dam.Multiple arches similarly transmit loads to the abutment or ends of the arch. This type of dam is suited to wider valleys. The main thrust and radial shears are transmitted to massive buttresses and then into the foundation material.Buttress dams include flat-slab, multiple-arch, roundhead-buttress, and multiple-dome types. The buttress dam adapts to all site locations. Downstream face slabs and aprons are used for overflow spillways similar to gravity dam spillways. Inclined sliding gates or light-weight low-head gates control the flow.The water loads are transmitted to the foundation by two systems of load-carrying members. The flat slabs, arches, or domes support the direct water load. The face slabs are supported by vertical buttresses. In most flat-slab buttress dams, steel reinforcement is used to carry thetension forces developed in the face slabs and buttress supports. Massive-head buttresses eliminate most tension forces and steel is not necessary.Combiantion designs may utilize one or more of the previously mentioned types of dams. For example, studies may indicate that an earthfill dam with a center concrete gravity overflow spillway section is the most economial in a wide, flat valley. Other design conditions may dictate a multiple-arch and buttress dam section or a buttress and gravity dam combination.Site ExplorationThe dam location is determined by the project’s functions. The exact site within the general location must be determined by careful project consideration and systematic studies.In preliminary studies, two primary factors must be determined-the topography at the site and characteristics of the foundation materials. The first choice of the type of dam is based primarily on these two factors. However, the final choice will usually be controlled by construction cost if other site factors are also considered.Asite exploration requires the preparation of an accurate topographic map for each possible site in the general location. The scale of the maps should be large enough for layout. Exploration primarily determines the conditions that make sites usable or unusable.From the site explorations, tentative sketches can be made of the dam location and project features such as power plants. Physical features at the site must be ascertained in order to make a sketch of the dam and determine the position of materials and work plant during construction. Other factors that may affect dam selection are roadways,fishways, locks, and log passages.TopographyTopography often determines the type of dam. For example, a narrow V-shaped channel may dictate an arch dam. The topography indicates surface characteristics of the valley and the relation of the contours to the various requirements of the structure. Soundness of the rock surface must be included in the topographic study.In a location study, one should select the best position for the dam. An accurate sketch of the dam and how it fits into the topographic features of the valley are often sufficient to permit initial cost estimates. The tentative location of the other dam features should be included in this sketch since items such as spillways can influence the type and location of the dam.Topographic maps can be made from aerial surveys and subsequent contour plotting or they can be obtained from governmental agencies. The topographic survey should be correlated with the site exploration to ensure accuracy. Topographic maps give only the surface profile at thesite. Further geological and foundation analyses are necessary for a final determination of dam feasibility.Foundation and Geological InvestigationFoundation and geological conditions determine the factors that support the weight of the dam. The foundation materials limit the type of dam to a great extent, although such limitations can be compensated for in design.Initial exploration may consist of a few core holes drilled along the tentatively selected site location. Their analysis in relation to the general geology of the area often rules out certain sites as unfeasible, particularly as dam height increases. Once the number of possible site locations has been narrowed down, more detailed geological investiagtions should be considered.The location of all faults, contacts, zones of permeability, fissures, and other underground conditions must be accurately defined. The probable required excavation depth at all points should be derived from the core drill analysis. Extensive drilling into rock formations isn’t necessary for small dams. However, as dam height and safety requirements increase, investigations should be increased in depth and number. If foundation materials are soft, extensive investigations should determine their depth,permeability, and bearing capacity. It is not always necessary orpossible to put a concrete dam on solid rock.The different foundations commonly encountered for dam construction are: (1)solid rock foundations, (2) gravel foundations, (3) silt or fine sand foundations, (4) clay foundations, and (5) nonuniform foundation materials. Small dams on soft foundation ( item 2 through item 5 ) present some additonal design problems such as settlement, prevention of piping, excessive percolation, and protection of foundation from downstream toe erosion. These conditions are above the normal design forces of a concrete dam on a rock foundation. The same problems also exist for earth dams.Geological formations can often be pictured in cross-section by a qualified geologist if he has certain core drill holes upon which to base his overall concept of the geology. However, the plans and specifications should not contain this overall geological concept. Only the logs of the core drill holes should be included for the contractor’s estimates. However, the geological picture of the underlying formations is a great aid in evaluating the dam safety. The appendix consists of excerpts from a geologic report for the site used in the design examples.HydrologyHydrology studies are necessary to estimate diversion requirements during construction, to establish frequency of use of emergency spillways in conjunction with outlets or spillways, to determine peak dischargeestimates for diversion dams, and to provide the basis for power generation. Hydrologic studies are complex; however, simplified procedures may be used for small dams if certain conservative estimates are made to ensure structural safety.Formulas are only a guide to preliminary plans and design computations. The empirical equations provide only peak discharge estimates. However, the designer is more interested in the runoff volume associated with discharge and the time distribution of the flow. With these data, the designer knows both the peak discharge and the total inflow into the reservoir area. This provides a basis for making reliable diversion estimates for irrigation projects, water supply, or power generation.A reliable study of hydrology enables the designer to select the proper spillway capacity to ensure safety. The importance of a safe spillway cannot be overemphasized. Insufficient spillways have caused failures of dams. Adequate spillway capacity is of paramount importance for earthfill and rockfill dams. Concrete dams may be able to withstand moderate overtopping.Spillways release excess water that cannot be retained in the storage space of the reservoir. In the preliminary site exploration, the designer must consider spillway size and location. Site conditions greatly influence the selection of location, type, and components of a spillway. The design flows that the spillway must carry without endangering the dam areequally important. Therefore, study of streamflow is just as critical as the foundation and geological studies of the site.附录2外文翻译混凝土重力坝一个坝址的坝型选择，主要取决于地形、地质、水文和气候条件。
毕业设计-水利外文翻译
英文原文：Water Resources and Hydropower Engineering ConstructionDesign Layout[Key words] construction layout Fuzzy multiple attribute decisionmaking Water Resources and Hydropower Construction[Abstract] Analysis of affecting factors of the construction layout program characteristics that people value in identifying these indicators fuzzy constraints are difficult to give exact values, while decision-making process has been one of psychological, subjective will and the work experience and other aspects influence decision-making process and therefore there is certainly ambiguity.1, Water Resources and Hydropower Engineering Construction Layout FactorsConstruction advantages and disadvantages of the general layout scheme, involving many factors, from different angles to evaluate the evaluation factors generally have two categories, qualitative factors, and quantitative factors of a class. Qualitative factors are mainly: 1. Favorable production, easy to administer, facilitate the degree of life; 2. During the construction process, the degree of co-ordination; 3. The principal impact of construction and operation; 4. Meet the security, fire, flood prevention, environmental protection requirements; 5. Temporary Works and the combination of permanent works and so on. Indicators are mainly quantitative factors;1. Site preparation earthwork quantity and cost;2. The extent of use of earth excavation;3. Temporary works of construction work quantity and cost;4. Workload and a variety of materials, transport costs;5. Size and cost of land acquisition;6. Made to the area to field, the recovery or recycling construction fees.As the construction is construction planning layout content, is that people under work experience, combined with engineering data on the occurrence of a future prediction about. Therefore, both qualitative factors, and the quantitative factors, there is uncertainty. We know that the uncertainty of two different forms; one is uncertain whether the incident occurred in 11 random, the event itself the state of uncertainty 11 ambiguity. Randomness is an external cause in general uncertain, but ambiguity is an inherent uncertainty of the structure. From the information point of view, therandomness involves only the amount of information, while the ambiguity is related to the meaning of information. We can say that ambiguity is more profound than the randomness, the uncertainty more generally, especially in the subjective understanding of areas of role ambiguity is much more important than the role of randomness. Random people for a lot of research has been carried out, achieved fruitful results; while ambiguity was ongoing and in-depth knowledge and research in the. All people involved in the system, carried out by people planning, feasibility studies, evaluation of decision-making, design and management, and therefore, can not ignore the objective world of things in the human brain, one by one to reflect the uncertainty of ambiguity, it is an objective difference intermediate division caused by the transition of a kind of uncertainty. Construction Layout Design is no exception, in the arrangement of construction there are a large number of objective fuzzy factors. For example, the construction of facilities, coordination between the levels of "good" and "general" is an accurate value can not be described. Therefore, the arrangement can not ignore or avoid the construction of the fuzziness existing in the process, but should be objective and deal with ambiguity of this objective, understand the rules for people planning, demonstration, evaluation and decision, design and management to provide a scientific basis and methods.As the construction layout of the content involved in more programs fuzzy factors exist, the traditional construction arrangement he considered the existence of ambiguity, but in decision-making process has fuzzy information precision, not a real fuzzy optimization. Therefore, the program should focus on optimization of fuzzy factors into account, the ambiguity should be reflected in the decision-making on the index, index weights. For quantitative indicators, mainly the amount and cost of the project issues, its value can be found in engineering materials and design documents to determine by calculation, the results are the values of the parameters and experience. As every engineer's understanding of things is not the same experience in a certain range of parameter changes, the results also in a certain range. For qualitative indicators, according to experts, engineering experience, through expert scoring method, set the value of statistics to determine. Such subjective factors, the knowledge structure and decision-making preferences play a major role. But in practice, due to the complexity of objective things and the people's thinking on the use of fuzzy concept, to describe with precision the number becomes very difficult, but with "some", "left"and the like get fuzzy concept to describe the more reasonable. Determine the weights of evaluation indexes, there are many mathematical ways to determine the accurate calculation. We know, for different projects, in the same factors, their importance is not the same, then the mathematical model is difficult to fully reflect the actual situation, the help of experts in engineering experience must be judged.Since the existence of the above ambiguity, avoid or ignore the ambiguity is unscientific, incomplete. Previous index value that decision-making, decision weights for programs for determining the value of the preferred method, there is bound to sidedness and limitations. As technology develops, people are increasingly demanding of precision, the object of study become more complicated, as complicated to some degree after the meaning of the precise cognitive declines and the appropriate fuzzy but accurate. Here, the introduction of fuzzy mathematical tools, the use of modern fuzzy multiple attribute decision making theory, Fuzzy multiple attribute decision making model, can exist for people to consider the ambiguity of the objective, to provide strong support for rational decision-making.2, Water Resources and Hydropower Engineering Construction Design LayoutConstruction Layout as a focus of the system around the concrete layout of the temporary structures. There are 1. All kinds of storage, stockpile and Spoil; 2. Mechanical repair system; 3. Metal structure, mechanical and electrical equipment and construction equipment installed base; 4. Wind, water and electricity supply systems; 5. Other construction plant, such as steel processing, wood processing, prefabricated factory; 6. Office and living space, such as offices, laboratories, dormitories, hospitals, schools, etc.; 7. Fire safety facilities and other, such as fire stations, guard, and security cordon so. At this time, various types of temporary structures should be put forward, the construction of facilities furnished a list of partial pressure, their area, building area and volume of construction and installation; on fertilization with an estimate of land acquisition, land area and the proposed land use plan, the study to reclaiming land in the use of the measures, site preparation earthwork volume calculations, the integrated cut and fill balance of the proposed excavation of the use of effective planning.Construction of facilities in order to avoid conflict between the layouts, construction of facilities in the analysis of adjacency relations, is to analyze the relationship between the construction of facilities, strength of correlation andrelationship. Usually based on the adjacency relationship, consider the construction schedule, construction strength, facilities operation and logistics. Analysis of the size and layout of the construction of facilities present at the location of the ground between the site controlled the indicators are: 1. The scale of construction facilities layout, the main considerations to meet the construction requirements of the case, the construction of facilities, capacity and layout area. 2. Foundation bearing capacity of the construction of facilities to consider geology, slope stability and so on. 3. Hydrological requirements and construction guide closure of the case, consider the different construction periods, flood, water table, water level changes in the construction site layout planning of construction restrictions and impact. 4. The height difference logistics constraints, considering logistics and vertical elevation gradient lines, logistics of import and export. 5. Construction of the distance between these facilities and restrictions, mainly refers to the construction of facilities necessary for running the minimum operating radius, the minimum limit transportation question, minimum import and export logistics, construction and facilities, the safety distance between. 6. Construction site area of internal and external traffic conditions, construction equipment, consider the minimum safe height and width of the transport, building materials inside the transport requirements.To be concrete system facilities arranged in a prominent position, so that interference by the other facilities as small as possible, the need for construction of facilities at this time analysis of the relationship between the adjacent, as many facilities for Hydropower Construction, different facilities have a clear focus on functionality, such as depots, gas stations, etc., if not for the neighbor relations analysis, because the construction of facilities for the inter-functional conflict, construction and project management to bring incalculable damage and safety hazards buried.References:[1] Lu Yu Mei editor of the Three Gorges Dam Construction [M]. Beijing: China Electric Power Press, 2003[2] Wei-Jun Zhu, Zhang Xiaojun and so the overall layout design of the Three Gorges Project Construction [J]. The people of the Yangtze River, 2001.32 (10) :4-5.译文：水利水电工程施工的布置方案设计[关键词]施工布置模糊多属性决策水利水电施工[论文摘要]分析施工布置方案的影响因素特点，指出人们在确定这些指标值时受到模糊性因素的限制很难给出精确值，同时决策过程还受到人们心理、主观意愿和工作经验等多方面的影响，因而决策过程也必然存在模糊性。
毕业设计毕业论文水电站文献翻译中国水利发电的现状和前景中英文对照
外文资料China's hydroelectric power the current situation and prospectsAbstract: The electricity is a modern industrial production and the life of an essential driving force for energy, hydroelectric power industry is a category. The founding of the past 50 years, China's hydropower industry has developed by leaps and bounds, has made remarkable achievements. The rise of hydropower in China there is a profound background.Key words: Hydro-electric power Status ProspectsFirst, China has a large-scale utilization of water resources and the need for the conditions. China's abundant hydropower resources, whether they are reserves of hydropower resources, or the possible development of hydropower resources in the countries in the world in the first rank. But China's energy utilization rate is only 13 percent, hydropower prospects are bright. As China's rapid economic growth, total energy consumption is also up sharply, coal, oil and gas these conventional energy consumption growing, or even need to rely on imports. It is estimated that by 2010 China's need to import about 100 million t of oil, and its dependence on imports will reach 40 percent or even higher. In such a situation, the development of new energy was particularly important and urgent. The water is a renewable and new energy, an inexhaustible supply of it.Second, the development of hydropower is also the need for environmental protection. Conventional power generation, coal combustion emissions in the course of a large number of hazardous substances so that the atmospheric environment is seriously contaminated, and acid rain caused "greenhouse effect", and many other environmental problems. And nuclear power generation have great potential risk, once the pollution caused by leakage, damage to the environment is immeasurable role. Hydro-electric power is not emissions of harmful gases,dust and ash, and no nuclear radiation pollution, is a clean power production, has obvious advantages.Third, hydro-electric power after more than a century of development, construction technology, manufacturing technology and hydro-generator groups in the transmission technology improved, stand-alone capacity has been increased. And low-cost hydro-electric power, running the high reliability, the extremely rapid development.1 Overview of China's hydropower resourcesChina's many rivers, rich runoff, huge gap, contains abundant hydropower resources. According to statistics, China's river water resources reserves 676 million kw, the generating capacity of 592.2 billion kwh; possible development of hydropower resources of the installed capacity of 378 million kw, the generating capacity of 920 billion kwh.Due to climate and topographical factors such as topography of the impact of China's hydropower resources in different regions and different distribution is very uneven Basin; China's hydropower resources of the river is a prominent characteristic of the steep river, the huge gap, originated the "roof of the world" Qinghai-Tibet Plateau of the Yangtze River, Yellow River and Yarlung Zangbo River, Lancang River, Nujiang River, the natural differences are about as high as 5000 m, forming a series of the world's largest rivers divide, which is not found in other countries. Full understanding of the characteristics of China's hydropower resources can be in the development process in light of local conditions, reasonably full use of hydropower resources.2 status quo of China's hydropower developmentA century, particularly since 1949, after several generations of hydropower builders of hard work, China's hydropower construction from small to large and from weak to strong continue to grow and develop. Since reform and opening up, utilities are building more rapid development of projects have been expanding. 1950s to the early 1960s, mainly repairing the dam and power station fullness, Dragon River. Gutian, and other minor works, initiated the development of small and medium hydropower (such as 114-8508, the Huaihe River, Huangtankou, Liuxihe, such as power stations). In the late 1950s in terms gradually mature, a number of rivers cascade development, such as Shizitan, salt Yanguoxia, Tuo River,Xinfengjiang, Xin'anjiang, the West-and cat jumping into a river to river at the works. The mid-1960s to the late 1970s during the period has started Gongzui, Yingxiuwan, Wujiangdu, Bikou, Fung Beach, Longyangxia, Baishan, Dahua and other projects. The early 1970s first 1000 MW installed capacity of the Liujiaxia Hydropower Station production. 2715 MW capacity of the 1980s the completion of the Gezhouba Hydropower Station, after a series of big hydropower stations have been building, 18200 MW capacity of the Three Gorges Project has started in 1994 and by the end of 2000, the 1000 MW larger than the largest hydropower station (not including Storage Power Station) has 18.In addition to conventional hydropower station, China's pumped-storage power station building has made great achievements. Pumped Storage Power Station was built in the main hydraulic fewer resources, to meet the needs of the power system peak load regulation. The construction of the main Pumped Storage Power Station are as follows:Guangzhou Pumped Storage Power Station to the total capacity of 2.4 million kw, is the first Block is currently the world's largest pumped-storage power station. Power station construction in two phases with a total capacity of eight, each lasting four and a capacity of 300,000 kw reversible high parameters of pumped storage units, the design of head 535 m, rated speed 500 r / min, comprehensive efficiency of 76 percent.Jiang Tianhuangping Pumped Storage Power Station, a total installed capacity of 1.8 million kw, a regulation on pure pumped storage power station, power consumption, pumping 4.28 billion kwh. North China Power Grid's largest pumped-storage power plant Ming Tombs Pumped Storage Power Station, "the Ming Tombs Reservoir" for the next pool, using plastic concrete cutoff wall hanging seepage control technology, power plants to install four 200,000 kw Francis River inverse-turbine pumps, an electric generating units, the installed capacity of 800,000 kw.Hebei Panjiakou hybrid pumped-storage power station, equipped with a conventional Taiwan 150,000 kw hydro-generator group, there are three pumped-storage units, each of 90,000 kw, total installed capacity of 420,000 kw.In addition, China's construction in Tibet also has the world's highest Pumped Storage Power Station Yangzhuoyong Lake pumped-storage power station. Pumped Storage PowerStation is also available in other Baoquan pumped storage power plant in Henan, Anhui Langyashan Pumped Storage Power Station, Shandong Taian Pumped Storage Power Station, Tongbai Pumped Storage Power Station in Zhejiang, Yixing in Jiangsu Pumped Storage Power Station, Hebei Zhang Nihewan Pumped Storage Power Station.3 China's hydropower development problems facing theChina's hydropower industry in nation-building after a considerable development, but there are still many problems. For example, the Ertan Hydropower Station in Sichuan Province since 1949 is the most intensive investment, the largest engineering, technical difficulty of the highest building projects, but an operation on the face of the enormous waste of resources and enterprises to huge losses this embarrassing position. The situation prevailing in China's hydropower station. The reasons were mainly the following points.First, the management system, a high degree of monopoly power industry system hindered the development of hydropower. China's Ministry of Water Resources and Ministry of Water and Power and management, and water conservancy and hydroelectric power is the power of the integrated projects, but the Ministry and its subordinate electric power throughout the production and scheduling system none of the staff from thermal power systems, power industry from nature Or that a high degree of monopoly industries, enterprises full control of a single power scheduling, power distribution, electricity sales, electricity billing and other powers. At the same time the electricity market in the period of relative surplus of hydroelectric power, thermal power contradiction between the very sharp and in China under the present circumstances, the priority use of hydropower resources can not be guaranteed, a large number of hydropower resources have been wasted. Hydropower and the Internet generally low tariffs, we can imagine the state of hydropower stations. Opening up the electricity market, breaking the monopoly of the power industry system, water and electricity problem is to solve the fundamental way. At the same time, the Internet tariff for water and electricity reform, "debt service tariff" that electricity tariff structure to a single bi-use electricity price of the electricity tariff structure.Secondly, in the current economic interests, the number of thermal power production, with the size of the economic benefits are directly related to mine. China's long-term mainly to thermal power, thermal power plants with their long-established fixed in a coal mine, if weuse water and electricity to replace thermal power, thermal power plants will face not only the pressure, coal will face great pressure, resulting in thermal power plants and coal mines Two aspects of the economic difficulties. Therefore, departments or units by the economic interests of the drive to form a "protective thermal power and hydropower light" situation, and this caused a lot of hydropower resources have been wasted, and even disposable loss of electricity consumption significantly higher than the actual Internet.Third, technically, since the peak shaving or water and electricity load rejection is relatively easy, even a few minutes to complete the start-up of large hydropower generating units and electricity networks, or stopping, and at the same level of capacity thermal power unit may need a few 10 hours to complete the start or stop. Therefore, in the scheduling grid, the hydropower generating units are often used to peak shaving or backup units, in sufficient water to flood when the power generation, but its importance in the era of conventional power generation applications, resulting in the huge waste of water and electricity.In short, the cause of China's water and electricity problems faced by people in the final analysis is ideologically not aware of the need for the development of hydropower and urgency of water and electricity often because there are one-time investment objective, long construction period, less completed early return The characteristics, and only on the immediate economic interests, water and electricity to the development of multiple objective of the resistance. Therefore, we should vigorously promote the development of hydropower in China is by the great significance of changing the concept of water and electricity, essentially wiping out all kinds of obstacles.4 China's hydropower development prospectsWith the deepening of reform and national economic development, China's electricity market situation has undergone fundamental changes from the previous power and capacity of the "double vacancy" into a relative surplus of electricity and peak shaving a serious shortage of capacity, to the development of hydropower A good opportunity.4.l general principleNow and in the future some time, China's hydropower development should be the main priority and good regulation of hydropower stations and power industry from all socio-economic development point of view and consider comprehensive study on hydropower development and strength and to prevent waste; reasonable evaluation Pumped Storage Utility economic benefits, fully aware of the pumped-storage power station filled valley, peak shaving, FM, PM, incidents such as back-up role in the importance of coordinated development in the eastern part of the pumped-storage power station; further strengthen water and electricity "basins, Cascade, and rolling, comprehensive "way of development; pay more attention to ecological problems.4.2 ladder to development and construction of hydropower baseChina's hydropower resources are mainly located in the western region, accounting for more than three quarters, but the current development rate of eight percent. Especially Yunnan Province, the province's total installed hydropower capacity can be developed about 90 million kw, the country's total installed capacity of hydropower development can be 23.8 percent, ranking the second in the provincial water resources are mainly located in the Jinsha River, Lancang River, Nujiang River, Pearl River, Red River and the Irrawaddy, such as Jiang's six major river systems, in western China is the most potential for hydropower development of the main provinces. However, Yunnan Province's industrial base is relatively backward, electricity and water resources are mainly located in the inconvenience of cross mountains, the development more difficult. With the great western development strategy for the implementation of the West, East project will lose the activation of the rich hydropower resources, and promote the cause of China's hydropower development. Yunnan Province to play the regional advantages, to build China's hydropower energy base, and the West, East lose, both local economic development to meet the demand for electricity, but also optimize the country's energy structure.At present, Chuan Xinan than the total installed capacity of the Three Gorges Power Station is also a 600,000 kw of the Xiluodu and Xiangjiaba hydropower station two giant project formally approved by the State Council, which will be China's largest hydropower base. Luobo River Power Station in Leibo County in Sichuan Province and Yongshan County in Yunnan Province at the junction of the design capacity of 12.6 million kw, the average annual generating capacity of 57.12 billion kwh; Xiangjiaba Hydropower Station located in Yibin County, Sichuan Province and Yunnan Province Fuxian water at the junction, thecapacity of 6 million kw, the average annual generating capacity of 30.7 billion kwh. That the construction of two power stations with a strong ability to adjust, less farmland inundated, immigration and other less one of the advantages of large-scale hydropower stations. The two giant hydropower station project marks the official start of China's large-scale development of hydropower resources of the upper reaches of the Yangtze River, the upper reaches of the Yangtze River hydropower resources development will greatly improve China's power structure, lay the West, the East lost the general pattern of nationwide The energy balance and optimize the allocation.4.3 continue to attach importance to the development of small hydropowerChina's small hydropower resources are very rich reserves of around 150 million kw, to develop capacity is about more than 70 million kw, in the corresponding generation of about 200 billion - 250 billion kwh. Small Hydropower in addition to large-sized hydropower is not the atmospheric pollution, the use of renewable energy without the worry of energy depletion, low-cost advantages of its resources, He scattered on the negative impact on the ecological environment, the technology is mature, less investment, easy to build, Therefore suitable for the rural and mountainous areas, especially rural and mountainous areas in developing countries.China, as developing countries, small hydropower construction has made great achievements, to the end of 1997, China's total installed capacity of small hydropower has reached 20.52 million kw, the generating capacity of 68.3 billion kwh. Small hydropower construction in most cases can be the local building materials to absorb the local labor force building, thereby reducing construction costs, and easier to standardize their equipment, can reduce the cost and shorten the construction period, no complicated expensive technology is conducive to China's economic underdevelopment in the mountains and Achieving rural electrification, which should continue to attach importance to its development and construction.中国水利发电的现状和前景摘要：电力是现代化工业生产和生活不可或缺的动力能量，水力发电是电力工业的一个门类。
水利水电英语课文翻译
水利水电英语课文翻译水利水电英语课文翻译课文翻译需要掌握一定的词汇和技巧，当然英语课文翻译可以帮助提高学生的英语水平。
以下是店铺整理的水利水电英语课文翻译，欢迎阅读。
水利水电英语课文翻译1：Lesson 1 importance of water 水的重要性Water is best known and most abundant of all chemical compounds occurring in relatively pure form on the earth‘s surface. Oxygen, the most abundant chemical element, is present in combination with hydrogen to the extent of 89 percent in water. Water covers about three fourths of the earth's surface and permeates cracks of much solid land. The Polar Regions are overlaid with vast quantities of ice, and the atmosphere of the earth carries water vapor in quantities from 0.1 percent to 2 percent by weight. It has been estimated that the amount of water in the atmosphere above a square mile of land on a mild summer day is of the order of 50,000 tons.在地球表面以相对纯的形式存在的一切化合物中，水是人们最熟悉的、最丰富的一种化合物。
水利水电毕业设计外文文献翻译
水工建筑物，29卷，9号，1995旋涡隧道溢洪道。
液压操作条件M . A .戈蓝，B. zhivotovskii，我·诺维科娃，V . B .罗季奥诺夫，和NN罗萨娜娃隧道式溢洪道，广泛应用于中、高压液压工程。
因此研究这类溢洪道这是一个重要的和紧迫的任务，帮助在水工建筑中使用这些类型的溢洪道可以帮助制定最佳的和可靠的溢洪道结构。
有鉴于此，我们希望引起读者的注意，基本上是新的概念（即，在配置和操作条件），利用旋涡流溢洪道[1，2，3，4 ]。
一方面，这些类型的溢洪道可能大规模的耗散的动能的流动的尾段。
因此，流量稍涡旋式和轴向流经溢洪道的尾端，不会产生汽蚀损害。
另一方面，在危险的影响下，高流量的流线型面下降超过长度时，最初的尾水管增加的压力在墙上所造成的离心力的影响。
一些结构性的研究隧道溢洪道液压等工程rogunskii，泰瑞，tel'mamskii，和tupolangskii液压工程的基础上存在的不同的经营原则现在已经完成了。
这些结构可能是分为以下基本组：-涡旋式（或所谓的single-vortex型）与光滑溢洪道水流的消能在隧道的长度时的研究的直径和高度的隧道；参看。
图1），而横截面的隧道是圆或近圆其整个长度。
涡旋式溢洪道-与越来越大的能量耗散的旋涡流在较短的长度- <（60——80）高温非圆断面导流洞（马蹄形，方形，三角形），连接到涡室或通过一个耗能（扩大）室（图2）[ 5，6 ]或手段顺利过渡断[ 7]；-溢洪道两根或更多互动旋涡流动耗能放电室[ 8 ]或特殊耗能器，被称为“counter-vortex耗能”[ 2，4 ]。
终端部分尾水洞涡流溢洪道可以构造的形式，一个挑斗，消力池，或特殊结构取决于流量的出口从隧道和条件的下游航道。
液压系统用于的流量的尾管可能涉及可以使用overflowtype或自由落体式结构。
涡旋式溢洪道光滑或加速[ 7 ]能量耗散的整个长度的水管道是最简单和最有前途的各类液压结构。
水利水电专业毕业设计外文翻译
毕业设计（论文）外文翻译题目水库及电力系统简介专业水利水电工程班级2007级四班学生陈剑锋指导教师杨忠超重庆交通大学2011 年RESERVOIRSWhen a barrier is constructed across some river in the form of a dam, water gets stored up on the upstream side of the barrier, forming a pool of water, generally called a reservoir.Broadly speaking, any water collected in a pool or a lake may be termed as a reservoir. The water stored in reservoir may be used for various purposes. Depending upon the purposes served, the reservoirs may be classified as follows: Storage or Conservation Reservoirs.Flood Control Reservoirs.Distribution Reservoirs.Multipurpose reservoirs.(1) Storage or Conservation Reservoirs. A city water supply, irrigation water supply or a hydroelectric project drawing water directly from a river or a stream may fail to satisfy the consumers’ demands during extremely low flows, while during high flows; it may become difficult to carry out their operation due to devastating floods. A storage or a conservation reservoir can retain such excess supplies during periods of peak flows and can release them gradually during low flows as and when the need arise.Incidentally, in addition to conserving water for later use, the storage of flood water may also reduce flood damage below the reservoir. Hence, a reservoir can be used for controlling floods either solely or in addition to other purposes. In the former case, it is known as ‘Flood Control Reservoir’or ‘Single Purpose Flood Control Reservoir’, and in the later case, it is called a ‘Multipurpose Reservoir’.(2) Flood Control Reservoirs A flood control reservoir or generally called flood-mitigation reservoir, stores a portion of the flood flows in such a way as to minimize the flood peaks at the areas to be protected downstream. To accomplish this, the entire inflow entering the reservoir is discharge till the outflow reaches the safe capacity of the channel downstream. The inflow in excess of this rate is stored in stored in the reservoir, which is then gradually released so as to recover the storage capacity for next flood.The flood peaks at the points just downstream of the reservoir are thus reduced by an amount AB. A flood control reservoir differs from a conservation reservoir only in its need for a large sluice-way capacity to permit rapid drawdown before or after a flood.Types of flood control reservoirs. There are tow basic types of flood-mitigation reservoir.Storage Reservoir or Detention basins.Retarding basins or retarding reservoirs.A reservoir with gates and valves installation at the spillway and at the sluice outlets is known as a storage-reservoir, while on the other hand, a reservoir with ungated outlet is known as a retarding basin.Functioning and advantages of a retarding basin:A retarding basin is usually provided with an uncontrolled spillway and anuncontrolled orifice type sluiceway. The automatic regulation of outflow depending upon the availability of water takes place from such a reservoir. The maximum discharging capacity of such a reservoir should be equal to the maximum safe carrying capacity of the channel downstream. As flood occurs, the reservoir gets filled and discharges through sluiceways. As the reservoir elevation increases, outflow discharge increases. The water level goes on rising until the flood has subsided and the inflow becomes equal to or less than the outflow. After this, water gets automatically withdrawn from the reservoir until the stored water is completely discharged. The advantages of a retarding basin over a gate controlled detention basin are:①Cost of gate installations is save.②There are no fates and hence, the possibility of human error and negligence in their operation is eliminated.Since such a reservoir is not always filled, much of land below the maximum reservoir level will be submerged only temporarily and occasionally and can be successfully used for agriculture, although no permanent habitation can be allowed on this land.Functioning and advantages of a storage reservoir:A storage reservoir with gated spillway and gated sluiceway, provides more flexibility of operation, and thus gives us better control and increased usefulness of the reservoir. Storage reservoirs are, therefore, preferred on large rivers which require batter controlled and regulated properly so as not to cause their coincidence. This is the biggest advantage of such a reservoir and outweighs its disadvantages of being costly and involving risk of human error in installation and operation of gates.(3) Distribution Reservoirs A distribution reservoir is a small storage reservoir constructed within a city water supply system. Such a reservoir can be filled by pumping water at a certain rate and can be used to supply water even at rates higher than the inflow rate during periods of maximum demands (called critical periods of demand). Such reservoirs are, therefore, helpful in permitting the pumps or water treatment plants to work at a uniform rate, and they store water during the hours of no demand or less demand and supply water from their ‘storage’ during the critical periods of maximum demand.(4) Multipurpose Reservoirs A reservoir planned and constructed to serve not only one purpose but various purposes together is called a multipurpose reservoir. Reservoir, designed for one purpose, incidentally serving other purpose, shall not be called a multipurpose reservoir, but will be called so, only if designed to serve those purposes also in addition to its main purpose. Hence, a reservoir designed to protect the downstream areas from floods and also to conserve water for water supply, irrigation, industrial needs, hydroelectric purposes, etc. shall be called a multipurpose reservoir.水库拦河筑一条像坝的障碍时，水就被拦蓄在障碍物的上游并形成水塘．通常称之为水库。
建筑设计：水利水电工程专业(水文与水资源篇)中英文对照翻译
水利水电工程专业〔水文与水资源篇〕中英文对照翻译水利水电工程专业〔水文与水资源篇〕中英文对照翻译1. Hydrological Cycle and BudgetHydrology is an earth science. It encompasses the occurrence, distribution, movement, and properties of the waters of the earth and theirenvironmental relations. Closely allied fields include geology, climatology, meteorology and oceanography.水文学是一门地球科学。
它包含地球水资源的发生、分布、运动和特质，以及其环境关系。
与之密切相关领域包括地质学，气候学，气象学和海洋学。
The hydrologic cycle is a continuous process by which water is transported from the oceans to the atmosphere to the land and back to the sea. Manysub-cycles exist. The evaporation of inland water and its subsequent precipitation over land before returning to the ocean is one example. The driving force for the global water transport system is provided by the sun, which furnishes the energy required for evaporation. Note that the water quality also changes during passage through the cycle; for example, sea water is converted to fresh water through evaporation.水文循环是一个连续的过程，在这个过程中水从海洋被运输到大气中，降落到陆地，然后回到海洋。
华北水利水电大学水利水电工程毕业设计外文翻译
DESIGN CONSIDERATIONS OF A HIGH ROCKFILL DAMNAM NGUM 2 CFRD, LAO PDRRuedi Straubaar1, Eva van Gunsteren2 and Stephen Moll31Geotechnical and Dam Engineering Expert, Pöyry Energy Ltd. (formerly Electrowatt Engineering Ltd.)Hardturmstrasse 161, CH-8037 Zurich, SwitzerlandE-mail: ruedi.straubhaar@2 Project Engineer and Assistant Project Manager for Nam Ngum 2, Pöyry Energy Ltd. (formerly Electrowatt Engineering Ltd.) Hardturmstrasse 161, CH-8037 Zurich, SwitzerlandE-mail: eva.van-gunsteren@3 Dam Engineer, Pöyry Energy Ltd. (formerly Electrowatt Engineering Ltd.) Hardturmstrasse 161,CH-8037 Zurich, SwitzerlandE-mail: stephen.moll@Abstract: Nam Ngum 2 dam, a large concrete face rock fill dam (CFRD) of 182 m height, is under construction and impounding is scheduled to start at beginning of April 2010. The dam is situated in a narrow valley and founded on sedimentary rock of variable strength.Dam design principles comprising dam zoning, face slab design and instrumentation are outlined. Foundation treatment including groutingand measures below the plinth are presented. The properties of the available rockfill materials and their influence on the dam zoning are discussed.Emphasis is given to the rockfill properties and placement procedures which influence dam behaviour during construction, impounding and operation.Key words: CFRD, Rockfill, Face Slab, Instrumentation1Nam Ngum 2 Hydropower SchemeThe Nam Ngum 2 (NN2) hydropower scheme is located on the Nam Ngum river in Lao PDR, about90 km north of the capital city of Vientiane and some 35 km upstream of the existing Nam Ngum 1dam and powerhouse. With an installed capacity of 615 MW, the project will produce energy for the Thai electricity grid. A significant component of the scheme is the 182 m high concrete face rock fill dam, with a volume of 9.5 M m3 and a crest length of 500 m. The dam will impound a reservoir with a volume of approximately 4.2 M m3.Construction of the NN2 Project commenced in late 2005 and is scheduled for completion in the second half of 2010. Rock fill placement in the dam body commenced in January 2008, and will be finished in early November 2009. Face slab construction, which is divided into an upper and lower stage, commenced in December 2008 and will becompleted by beginning of April 2010, when impounding will begin. The reservoir will fill during one rainy season, enabling commissioning to take place during the second half of 2010.2Considerations with respect to dam deformationsConcrete face rock fill dams are considered inherently safe for a wide range of weak and strong rock fill (Cooke 1991) and deformation of the rock fill is often assumed not being a governing concern provided the dam is well engineered and the dam foundation is of adequate quality. It is often assumed that dam settlements are a simple function of the dam height and that they are not likely to exceed 1 % of the compacted fill height with horizontal deformations less than 50 % of the settlements. Predictions are also often made based on laboratory tests and dam deformation analyses.2.1 Rock fill testing performed for NN2 CFRDFor the construction of the NN2 dam quarried rock of sedimentary formations are available. The source material, consisting basically of sandstone and siltstone, has been investigated by drilling, quarry trials, laboratory testing and trial embankment construction. The essential tests are index property tests, compressive strength and basic friction angle tests. Tests were also performed on saturated specimen, which normally gives more representative lower values.Of particular interest are always large scale triaxial and compressibility tests, which have been carried out for NN2 by the IWHR1 in China.2.2 Dam analyses and zoning of NN2 CFRDTest results from the IWHR as well as results from the AIT2 and site laboratories were used as basis for dam analyses. Stability as well as 2D and 3D deformation analyses were carried out by the IWHR. Based on the results of the analyses and also based on visual observation which indicated a very high desintegration potential of the siltstone, it had to be concluded that only sandstone is suitable as rock fill for the construction of the high embankment. By using only sandstone for rock fill it was concluded that the dam deformation will be within acceptable and normal limits.During construction it was observed that also fine grained sandstone, porous or weathered sandstone of moderate quality is being obtained from quarrying which can not always completely be separated and wasted. Therefore the dam zoning was adjusted to permit also placement of lower quality rock fill in the central part of the dam embankment. The adjusted dam zoning is shown in Figure 2.3 Observed deformations on constructed damsOften it is assumed that for strong rock fills the settlements are small,less than about 1% of the fill height. It is further commonly assumed that the settlements develop essentially during construction.Although these assumptions were correct for many dams, a few dams did show much more settlements (Kjaernsli et al. 1992). More recent data of observed crest settlements are presented in Figure 3.For the 165 m high Atatürk dam in Turkey high post construction settlements developed. The post construction settlement rate of 0.02 % per year, which can be considered as maximum acceptable creeping pace after impounding, is even 10 years after completion of construction still exceeded.It has to be taken as a fact that deformations often exceed common values and are not always predictable. Laboratory tests are restricted to small maximum particle sizes and do not always reflect the behaviour of large size rock fill.4 Factors influencing the deformations of rock fill damsFactors influencing the magnitude of settlements are discussed in the following. Some information are taken from an unpublished research by Victor Milligan and Lisa Coyne “Review of factors influencing the settlement of rock fill dams”.4.1 Particle size and shapeThere is evidence that the modulus of deformation increases withincreasing particle size. Tests by Marachi et al. (1969) indicated that compressibility is highest for 150 mm particle size and least for 12 mm particle size. It has to be assumed that for particle sizes exceeding 150 mm the compressibility will further increase. A similar effect has to be assumed for the shear strength of rock fill. Increasing particle size somewhat reduces the shear strength depending on the basic characteristics of the source rock.The effect of particle shape on compressibility is well known. McDowell et al. (2004) stated that the “particle shape seems to have a greater effect (on compressibility) than mineralogy”. There is a pronounced reduction in modulus as the particle shape changes from rounded to angular.4.2 Gradation and state of packingIt is well known that uniformly graded rock fill is much more compressible than broadly graded rock fill. In general a uniformity coefficient of 30 is desired to obtain a reasonable gradation.Gradation and density have an essential effect on the state of packing.4.3 Wetting and compactionThe method of rock fill placement has a considerable influence on the compressibility of the rock fill.Water added to the rock fill weakens the rock and induces breakage and crushing of the rock particles, inparticular if the rock fill particles have a relatively high porosity. This will in general cause increased settlement and result in an increase of the long term stiffness of the fill. It is also well known that with smaller lift thicknesses and increased compaction energy the dam deformations are reduced.4.4 Effects of degradationDegradation depends on the stress level and the strength of the rock particles. Under a given stress level, the breakage of rounded particles is much less than that of angular particles. Well graded rounded particles have more contact points and thus experience less stress at contact points. In contrast uniform and sharply shaped particles experience much higher stresses at contact points with an increasing potential for particle breakage and creep.4.5 Predicted versus observed settlementsAlthough the various factors affecting the compressibility of rockfill are well known, it is not always possible to predict the dam deformation with the desired reliability. Laboratory testing and analytical modeling may not be sufficient to conclude on the dam behaviour, in particular the long term creeping of the structure. It is a fact that the observed deformation can exceed the predicted ones.Some of the factors influencing the compressibility can be controlledby the construction methodology. Other factors as the particle shape and strength can not be influenced, they are rather given by the rock type.Important is an adequate instrumentation of the dam and to compare the observed behaviour of the dam with the predictions and observations.4.6 Rock fill used at NN2For NN2, the conditions of the rock fill are as follows:- The particle size of the rock fill is relatively large and the particle shape is quite angular.- The gradation of the rock fill is often uniform and gap-graded, with a lack of rock fragments of gravel size.- The densities obtained after placement are adequate, although segregated areas observed may lead to increased post construction settlements.- Due to the gap grading and the high sand content, wetting of the fill leads to the development of a mud layer on the rock fill surface, which needs to be removed.- The amount of water effectively added to the fill is around 100-150 l/m3 which is considerably lower than the initially foreseen amount of 250 l/m3.The currently available information from settlement monitoring data indicate that there is a significant increase of settlements at higher stresslevels and also a tendency of quite pronounced creep settlements. The modulus of deformation during construction has decreased from initial values as high as 150 to 200 MPa to currently quite low to moderate values of around 30 to 70 MPa.5 Foundation TreatmentThe geological formations at the dam site consist of medium bedded to massive cliff-forming sandstone and interbedded thin to thick bedded siltstone. Three easterly trending folds whose axes are nearly perpendicular to the Nam Ngum river are present at the dam site. The cliff-forming sandstone is generally slightly jointed to massive, whereas the interbedded siltstone is moderately to closely jointed. The quality of the foundation rock varies within the following limits:- Sandstone: fresh, hard and slightly fractured to weathered and heavily fractured.- Siltstone: fresh and hard to weathered, soft and slaking.The foundation treatment at Nam Ngum 2 mainly aims on:- Positive control of seepage below the plinth.- Providing a stable and non-erodible foundation beneath and around the plinth.- Protection of foundation rock susceptible to erosion.- Levelling of abrupt irregularities in the dam foundation and very steep abutment slopes to reduce differential settlements.With respect to foundation treatment requirements the embankment foundation is divided into three areas. The foundation for the plinth is considered separately since it has more stringent requirements for rock quality and preparation.The upstream third of the embankment is founded on fresh to slightly weathered rock. The central part of the embankment is founded on slightly to moderately weathered rock. The requirements for the downstream third are less rigorous, and the foundation on moderately weathered rock is acceptable. At the riverbed the present dense alluvium of maximum 15 m thickness was left in place only in the central part of the dam body.Particular attention is paid to areas where the foundation of the dam consists of siltstone or highly weathered or intensively fractured sandstone. Such foundation rock is susceptible to erosion requires special protection. For this purpose a 100 mm wire mesh reinforced shotcrete blanket, covered by filters, is provided to cover the erodible rock within the foundation downstream of the plinth up to a distance of 0.3 H (H = reservoir head) from the plinth. In addition, and within the entire dam foundation area up to the downstream slope erodible foundation rock is。
毕业设计毕业论文水电站文献翻译中国水利发电的现状和前景中英文对照
外文资料China's hydroelectric power the current situation and prospectsAbstract: The electricity is a modern industrial production and the life of an essential driving force for energy, hydroelectric power industry is a category. The founding of the past 50 years, China's hydropower industry has developed by leaps and bounds, has made remarkable achievements. The rise of hydropower in China there is a profound background.Key words: Hydro-electric power Status ProspectsFirst, China has a large-scale utilization of water resources and the need for the conditions. China's abundant hydropower resources, whether they are reserves of hydropower resources, or the possible development of hydropower resources in the countries in the world in the first rank. But China's energy utilization rate is only 13 percent, hydropower prospects are bright. As China's rapid economic growth, total energy consumption is also up sharply, coal, oil and gas these conventional energy consumption growing, or even need to rely on imports. It is estimated that by 2010 China's need to import about 100 million t of oil, and its dependence on imports will reach 40 percent or even higher. In such a situation, the development of new energy was particularly important and urgent. The water is a renewable and new energy, an inexhaustible supply of it.Second, the development of hydropower is also the need for environmental protection. Conventional power generation, coal combustion emissions in the course of a large number of hazardous substances so that the atmospheric environment is seriously contaminated, and acid rain caused "greenhouse effect", and many other environmental problems. And nuclear power generation have great potential risk, once the pollution caused by leakage, damage to the environment is immeasurable role. Hydro-electric power is not emissions of harmful gases,dust and ash, and no nuclear radiation pollution, is a clean power production, has obvious advantages.Third, hydro-electric power after more than a century of development, construction technology, manufacturing technology and hydro-generator groups in the transmission technology improved, stand-alone capacity has been increased. And low-cost hydro-electric power, running the high reliability, the extremely rapid development.1 Overview of China's hydropower resourcesChina's many rivers, rich runoff, huge gap, contains abundant hydropower resources. According to statistics, China's river water resources reserves 676 million kw, the generating capacity of 592.2 billion kwh; possible development of hydropower resources of the installed capacity of 378 million kw, the generating capacity of 920 billion kwh.Due to climate and topographical factors such as topography of the impact of China's hydropower resources in different regions and different distribution is very uneven Basin; China's hydropower resources of the river is a prominent characteristic of the steep river, the huge gap, originated the "roof of the world" Qinghai-Tibet Plateau of the Yangtze River, Yellow River and Yarlung Zangbo River, Lancang River, Nujiang River, the natural differences are about as high as 5000 m, forming a series of the world's largest rivers divide, which is not found in other countries. Full understanding of the characteristics of China's hydropower resources can be in the development process in light of local conditions, reasonably full use of hydropower resources.2 status quo of China's hydropower developmentA century, particularly since 1949, after several generations of hydropower builders of hard work, China's hydropower construction from small to large and from weak to strong continue to grow and develop. Since reform and opening up, utilities are building more rapid development of projects have been expanding. 1950s to the early 1960s, mainly repairing the dam and power station fullness, Dragon River. Gutian, and other minor works, initiated the development of small and medium hydropower (such as 114-8508, the Huaihe River, Huangtankou, Liuxihe, such as power stations). In the late 1950s in terms gradually mature, a number of rivers cascade development, such as Shizitan, salt Yanguoxia, Tuo River,Xinfengjiang, Xin'anjiang, the West-and cat jumping into a river to river at the works. The mid-1960s to the late 1970s during the period has started Gongzui, Yingxiuwan, Wujiangdu, Bikou, Fung Beach, Longyangxia, Baishan, Dahua and other projects. The early 1970s first 1000 MW installed capacity of the Liujiaxia Hydropower Station production. 2715 MW capacity of the 1980s the completion of the Gezhouba Hydropower Station, after a series of big hydropower stations have been building, 18200 MW capacity of the Three Gorges Project has started in 1994 and by the end of 2000, the 1000 MW larger than the largest hydropower station (not including Storage Power Station) has 18.In addition to conventional hydropower station, China's pumped-storage power station building has made great achievements. Pumped Storage Power Station was built in the main hydraulic fewer resources, to meet the needs of the power system peak load regulation. The construction of the main Pumped Storage Power Station are as follows:Guangzhou Pumped Storage Power Station to the total capacity of 2.4 million kw, is the first Block is currently the world's largest pumped-storage power station. Power station construction in two phases with a total capacity of eight, each lasting four and a capacity of 300,000 kw reversible high parameters of pumped storage units, the design of head 535 m, rated speed 500 r / min, comprehensive efficiency of 76 percent.Jiang Tianhuangping Pumped Storage Power Station, a total installed capacity of 1.8 million kw, a regulation on pure pumped storage power station, power consumption, pumping 4.28 billion kwh. North China Power Grid's largest pumped-storage power plant Ming Tombs Pumped Storage Power Station, "the Ming Tombs Reservoir" for the next pool, using plastic concrete cutoff wall hanging seepage control technology, power plants to install four 200,000 kw Francis River inverse-turbine pumps, an electric generating units, the installed capacity of 800,000 kw.Hebei Panjiakou hybrid pumped-storage power station, equipped with a conventional Taiwan 150,000 kw hydro-generator group, there are three pumped-storage units, each of 90,000 kw, total installed capacity of 420,000 kw.In addition, China's construction in Tibet also has the world's highest Pumped Storage Power Station Yangzhuoyong Lake pumped-storage power station. Pumped Storage PowerStation is also available in other Baoquan pumped storage power plant in Henan, Anhui Langyashan Pumped Storage Power Station, Shandong Taian Pumped Storage Power Station, Tongbai Pumped Storage Power Station in Zhejiang, Yixing in Jiangsu Pumped Storage Power Station, Hebei Zhang Nihewan Pumped Storage Power Station.3 China's hydropower development problems facing theChina's hydropower industry in nation-building after a considerable development, but there are still many problems. For example, the Ertan Hydropower Station in Sichuan Province since 1949 is the most intensive investment, the largest engineering, technical difficulty of the highest building projects, but an operation on the face of the enormous waste of resources and enterprises to huge losses this embarrassing position. The situation prevailing in China's hydropower station. The reasons were mainly the following points.First, the management system, a high degree of monopoly power industry system hindered the development of hydropower. China's Ministry of Water Resources and Ministry of Water and Power and management, and water conservancy and hydroelectric power is the power of the integrated projects, but the Ministry and its subordinate electric power throughout the production and scheduling system none of the staff from thermal power systems, power industry from nature Or that a high degree of monopoly industries, enterprises full control of a single power scheduling, power distribution, electricity sales, electricity billing and other powers. At the same time the electricity market in the period of relative surplus of hydroelectric power, thermal power contradiction between the very sharp and in China under the present circumstances, the priority use of hydropower resources can not be guaranteed, a large number of hydropower resources have been wasted. Hydropower and the Internet generally low tariffs, we can imagine the state of hydropower stations. Opening up the electricity market, breaking the monopoly of the power industry system, water and electricity problem is to solve the fundamental way. At the same time, the Internet tariff for water and electricity reform, "debt service tariff" that electricity tariff structure to a single bi-use electricity price of the electricity tariff structure.Secondly, in the current economic interests, the number of thermal power production, with the size of the economic benefits are directly related to mine. China's long-term mainly to thermal power, thermal power plants with their long-established fixed in a coal mine, if weuse water and electricity to replace thermal power, thermal power plants will face not only the pressure, coal will face great pressure, resulting in thermal power plants and coal mines Two aspects of the economic difficulties. Therefore, departments or units by the economic interests of the drive to form a "protective thermal power and hydropower light" situation, and this caused a lot of hydropower resources have been wasted, and even disposable loss of electricity consumption significantly higher than the actual Internet.Third, technically, since the peak shaving or water and electricity load rejection is relatively easy, even a few minutes to complete the start-up of large hydropower generating units and electricity networks, or stopping, and at the same level of capacity thermal power unit may need a few 10 hours to complete the start or stop. Therefore, in the scheduling grid, the hydropower generating units are often used to peak shaving or backup units, in sufficient water to flood when the power generation, but its importance in the era of conventional power generation applications, resulting in the huge waste of water and electricity.In short, the cause of China's water and electricity problems faced by people in the final analysis is ideologically not aware of the need for the development of hydropower and urgency of water and electricity often because there are one-time investment objective, long construction period, less completed early return The characteristics, and only on the immediate economic interests, water and electricity to the development of multiple objective of the resistance. Therefore, we should vigorously promote the development of hydropower in China is by the great significance of changing the concept of water and electricity, essentially wiping out all kinds of obstacles.4 China's hydropower development prospectsWith the deepening of reform and national economic development, China's electricity market situation has undergone fundamental changes from the previous power and capacity of the "double vacancy" into a relative surplus of electricity and peak shaving a serious shortage of capacity, to the development of hydropower A good opportunity.4.l general principleNow and in the future some time, China's hydropower development should be the main priority and good regulation of hydropower stations and power industry from all socio-economic development point of view and consider comprehensive study on hydropower development and strength and to prevent waste; reasonable evaluation Pumped Storage Utility economic benefits, fully aware of the pumped-storage power station filled valley, peak shaving, FM, PM, incidents such as back-up role in the importance of coordinated development in the eastern part of the pumped-storage power station; further strengthen water and electricity "basins, Cascade, and rolling, comprehensive "way of development; pay more attention to ecological problems.4.2 ladder to development and construction of hydropower baseChina's hydropower resources are mainly located in the western region, accounting for more than three quarters, but the current development rate of eight percent. Especially Yunnan Province, the province's total installed hydropower capacity can be developed about 90 million kw, the country's total installed capacity of hydropower development can be 23.8 percent, ranking the second in the provincial water resources are mainly located in the Jinsha River, Lancang River, Nujiang River, Pearl River, Red River and the Irrawaddy, such as Jiang's six major river systems, in western China is the most potential for hydropower development of the main provinces. However, Yunnan Province's industrial base is relatively backward, electricity and water resources are mainly located in the inconvenience of cross mountains, the development more difficult. With the great western development strategy for the implementation of the West, East project will lose the activation of the rich hydropower resources, and promote the cause of China's hydropower development. Yunnan Province to play the regional advantages, to build China's hydropower energy base, and the West, East lose, both local economic development to meet the demand for electricity, but also optimize the country's energy structure.At present, Chuan Xinan than the total installed capacity of the Three Gorges Power Station is also a 600,000 kw of the Xiluodu and Xiangjiaba hydropower station two giant project formally approved by the State Council, which will be China's largest hydropower base. Luobo River Power Station in Leibo County in Sichuan Province and Yongshan County in Yunnan Province at the junction of the design capacity of 12.6 million kw, the average annual generating capacity of 57.12 billion kwh; Xiangjiaba Hydropower Station located in Yibin County, Sichuan Province and Yunnan Province Fuxian water at the junction, thecapacity of 6 million kw, the average annual generating capacity of 30.7 billion kwh. That the construction of two power stations with a strong ability to adjust, less farmland inundated, immigration and other less one of the advantages of large-scale hydropower stations. The two giant hydropower station project marks the official start of China's large-scale development of hydropower resources of the upper reaches of the Yangtze River, the upper reaches of the Yangtze River hydropower resources development will greatly improve China's power structure, lay the West, the East lost the general pattern of nationwide The energy balance and optimize the allocation.4.3 continue to attach importance to the development of small hydropowerChina's small hydropower resources are very rich reserves of around 150 million kw, to develop capacity is about more than 70 million kw, in the corresponding generation of about 200 billion - 250 billion kwh. Small Hydropower in addition to large-sized hydropower is not the atmospheric pollution, the use of renewable energy without the worry of energy depletion, low-cost advantages of its resources, He scattered on the negative impact on the ecological environment, the technology is mature, less investment, easy to build, Therefore suitable for the rural and mountainous areas, especially rural and mountainous areas in developing countries.China, as developing countries, small hydropower construction has made great achievements, to the end of 1997, China's total installed capacity of small hydropower has reached 20.52 million kw, the generating capacity of 68.3 billion kwh. Small hydropower construction in most cases can be the local building materials to absorb the local labor force building, thereby reducing construction costs, and easier to standardize their equipment, can reduce the cost and shorten the construction period, no complicated expensive technology is conducive to China's economic underdevelopment in the mountains and Achieving rural electrification, which should continue to attach importance to its development and construction.中国水利发电的现状和前景摘要：电力是现代化工业生产和生活不可或缺的动力能量，水力发电是电力工业的一个门类。
[电力水利]毕业设计英语翻译水电方向[管理资料]
![[电力水利]毕业设计英语翻译水电方向[管理资料]](https://img.taocdn.com/s3/m/faf819fc844769eae109ed19.png)
Speed and Active Power Control of Hydro Turbine UnitAbstract—In the paper, the procedure is given for designing speed and active power controller of hydro turbine units. The procedure is based on mathematical models of the controlled system。
The controller parameters are obtained from closed-loop poles and hydro turbine parameters by derived analytical formulas over a wide range of the hydro turbine operating points. The described procedure allows the fast and direct determination of the controller parameters. There is no need for heuristic controller parameters tuning. Results from two hydro turbine units with the controllers designed using the described procedure are given as an illustration。
Index Terms—Governors, hydraulic turbines, power control, velocity control.I. INTRODUCTIONTHE WORK presented in this paper was motivated by problems presented during the development of the turbine governors for different hydro power plants (HPP). The main problem was to find suitable controller parameters bas ed on the mathematical model of the controlled system. That problem is somewhat described in [8] and [9]. However, the method for finding gains via an optimal control approach in [9] is time-consuming. The stability is not ensured for different loads.In [8], another method for optimal controller design is given. In [12], an interesting case study of governor tuning in frequency domain is represented, but no equations for general governor case are given. The model-based controller design procedure for determining governor parameters described in this paper is simple and natural. For the model-based controller design, it is necessary to create the appropriate mathematical model of the main system parts. Because the achieved model is nonlinear, to use linear controller design methods, it is necessary to line arize the model. Well-known proportional-integral-derivative/proportional-integral (PID/PI) controllers are chosen for controller structures be-cause of their widespread use. Then, designer has to chooseclosed-loop poles from the required characteristics of the con-rolled system (overshoot, rise time, settling time, etc.). The equations are derived that allow the designer to calculate the Manuscript received August 20, 2002; revised May 1, 2003. Paper no. TEC-00182-2002.B. Strah is with the Continental Temic—. Automotive Distance Control Systems GmbH, Lindau D-88131, Germany (e-mail:@).O. Kuljaca is with the Department of Advanced Technology, Alcorn State University, Lorman, MS 39096 USA (e-mail: okuljaca@). Z. Vukic is with the Faculty of Electrical Engineering and Computing, University of Zagreb, Zagreb 10000, Croatia (e-mail: @).Digital Object Identifier。
水利水电工程专业外文翻译、英汉互译、中英对照
水利水电工程专业外文翻译、英汉互译、中英对照毕业设计,论文，外文翻译题目姚家河水电站溢流坝及消能工优化设计专业水利水电工程使用CFD模型分析规模和粗糙度对反弧泄洪洞的影响12 作者 Dae Geun Kimand Jae Hyun Park摘要在这项研究中，利用CFD模型、FLOW-3D模型详细调查流量特性如流量、水面、反弧溢洪道上的峰值压力，并考虑到模型规模和表面粗糙度对速度和压力的垂直分布特征的影响，因此，在领域中被广泛验证和使用。
由于表面粗糙度数值的误差是微不足道的，对于流量，水面平稳，波峰压力影响较小。
但是我们只是使用长度比例小于100或200在可接受的误差范围的建筑材料一般粗糙度高度和规模效应的模型，最大速度在垂直的坐标堰发生更严重的粗糙度和规模效应。
原型的速度比缩尺比模型的更大，但现却相反1的。
在任何一节的最大速度略有降低或者表面粗糙度和长度的比例增加。
最大速度出现在上游水头的增加几乎呈线性增加溢洪道前的距离和位置较低的垂直位置位上。
关键词:FLOW-3D，反弧溢洪道，粗糙度效应，规模效应1.简介工程师在大多数情况下都选着设计建造具有过流高效、安全地反弧溢洪道，并且它在使用过程中具有良好的测量能力。
反弧溢洪道的形状是从较高顶堰的直线段流到半径R的网弧形段，在反弧附近的大气压力超过设计水头。
在低于设计水头时波峰阻力减少。
在高水头的时候，顶堰的大气压较高产生负压使水流变得更缓。
虽然这是关于一般反弧从上游流量条件下的变化、修改的波峰形状或改变航的形状和其流动特性的理解，但是道由于局部几何性质等的标准设计参数的偏差都会改变的水流的流动性，影响的分析结果。
物理模型被广泛的用来确定溢洪道非常重要的大坝安全。
物理模型的缺点是成本高，它可能需要相当长的时间得到的结果。
此外，由于规模效应的误差的严重程度增加原型模型的大小比例。
因此在指导以正确的模型细节时，计算成本相对较低物理建模、数值模拟，即使它不能被用于为最终确定的设计也是非常宝贵的资料。
毕业设计水利水电工程英文文献翻译
外文文献：hydraulicturbines and hydro—electric powerAbstractPower may be developed from water by three fundamental processes ：by action of its weight, of its pressure，or of its velocity，or by a combination of any or all three。
In modern practice the Pelton or impulse wheel is the only type which obtains power by a single process the action of one or more high-velocity jets. This type of wheel is usually found in high—head developments. Faraday had shown that when a coil is rotated in a magnetic field electricity is generated. Thus, in order to produce electrical energy, it is necessary that we should produce mechanical energy，which can be used to rotate the ‘coil’。
The mechanical energy is produced by running a prime mover （known as turbine ）by the energy of fuels or flowing water. This mechanical power is converted into electrical power by electric generator which is directly coupled to the shaft of turbine and is thus run by turbine. The electrical power, which is consequently obtained at the terminals of the generator，is then transited to the area where it is to be used for doing work.he plant or machinery which is required to produce electricity (i.e。
水利水电工程毕业设计英语翻译
外文资料翻译学院(直属系):能源与环境学院年级、专业: 2009级水利水电工程学生姓名:李巧龙学号: 3120指导教师:杨耀完成时间: 2013年 5 月 27 日hydraulic turbines1 introductionPower may be developed from water by three fundamental processes : by action of its weight, of its pressure, or of its velocity, or by a combination of any or all three. In modern practice the Pelton or impulse wheel is the only type which obtains power by a single process the action of one or more high-velocity jets. This type of wheel is usually found in high-head developments.There has been practically no increase in the efficiency of hydraulic turbines since about 1925, when maximum efficiencies reached 93% or more. As far as maximum efficiency is concerned, the hydraulic turbine has about reached the practicable limit of development. Nevertheless, in recent years, there has been a rapid and marked increase in the physical size and horsepower capacity of individual units.In addition, there has been considerable research into the cause and prevention of cavitation, which allows the advantages of higher specific speeds to be obtained at higher heads than formerly were considered advisable. The net effect of this progress with larger units, higher specific speed, and simplification and improvements in design has been to retain for the hydraulic turbine the important place which it has long held at one of the most important prime movers.2 types of hydraulic turbinesHydraulic turbines may be grouped in two general classes: the impulse type which utilizes the kinetic energy of a high-velocity jet which acts upon only a small part of the circumference at any instant, and the reaction type which develops power from the combined action of pressure and velocity of the water that completely fills the runner and water passages. The reaction group is divided into two general types: the Francis, sometimes called the reaction type, and the propeller type. The propeller class is also further subdivided into the fixed-blade propeller type, and the adjustable-blade type of which the Kaplan is representative.2.1 impulse wheelsWith the impulse wheel the potential energy of the water in the penstock is transformed into kinetic energy in a jet issuing from the orifice of a nozzle. This jet discharge freely into the atmosphere inside the wheel housing and strikes against the bowl-shaped buckets of the runner. At each revolution the bucket enters, passes through, and passes out of the jet, during which time it receives the full impact force of the jet. This produces a rapid hammer blow upon the bucket. At the same time the bucket is subjected to the centrifugal force tending to separate the bucket from its disk. On account of the stresses so produced and also the scouring effects of the waterflowing over the working surface of the bowl, material of high quality of resistance against hydraulic wear and fatigue is required. Only for very low heads can cast iron be employed. Bronze and annealed cast steel are normally used.2.2 Francis runnersWith the Francis type the water enters from a casing or flume with a relatively low velocity, passes through guide vanes or gates located around the circumstance, and flows through the runner, from which it discharges into a draft tube sealed below the tail-water level. All the runner passages are completely filled with water, which acts upon the whole circumference of the runner. Only a portion of the power is derived from the dynamic action due to the velocity of the water, a large part of the power being obtained from the difference in pressure acting on the front and back of the runner buckets. The draft tube allows maximum utilization of the available head, both because of the suction created below the runner by the vertical column of water and because the outlet of he draft tube is larger than the throat just below the runner, thus utilizing a part of the kinetic energy of the water leaving the runner blades.2.3 propeller runnersnherently suitable for low-head developments, the propeller-type unit has effected marked economics within the range of head to which it is adapted. The higher speed of this type of turbine results in a lower-cost generator and somewhat smaller powerhouse substructure and superstructure. Propeller-type runners for low heads and small outputs are sometimes constructed of cast iron. For heads above 20 ft, they are made of cast steel, a much more reliable material. Large-diameter propellers may have individual blades fastened to the hub.2.4 adjustable-blade runnersThe adjustable-blade propeller type is a development from the fixed-blade propeller wheel. One of the best-known units of this type is the Kaplan unit, in which the blades may be rotated to the most efficient angle by a hydraulic servomotor. A cam on the governor is used to cause the blade angle to change with the gate position so that high efficiency is always obtained at almost any percentage of full load.By reason of its high efficiency at all gate openings, the adjustable-blade propeller-type unit is particularly applicable to low-head developments where conditions are such that the units must be operated at varying load and varying head. Capital cost and maintenance for such units are necessarily higher than for fixed-blade propeller-type units operated at the point of maximum efficiency.hydro-electric powerFaraday had shown that when a coil is rotated in a magnetic field electricity is generated. Thus, in order to produce electrical energy, it is necessary that we should prod uce mechanical energy, which can be used to rotate the ‘coil’. The mechanical energy is produced by running a prime mover (known as turbine ) by the energy of fuels or flowing water. This mechanical power is converted into electrical power by electric generator which is directly coupled to the shaft of turbine and is thus run by turbine. The electrical power, which is consequently obtained at the terminals of the generator, is then transited to the area where it is to be used for doing work.he plant or machinery which is required to produce electricity (i.e. prime mover +electric generator) is collectively known as power plant. The building, in which the entire machinery along with other auxiliary units is installed, is known as power house.1 thermal and hydropowerAs stated earlier, the turbine blades can be made to run by the energy of fuels or flowing water. When fuel is used to produce steam for running the steam turbine, then the power generated is known as thermal power. The fuel which is to be used for generating steam may either be an ordinary fuel such as coal, fuel oil, etc., or atomic fuel or nuclear fuel. Coal is simply burnt to produce steam from water and is the simplest and oldest type of fuel. Diesel oil, etc. may also be used as fuels for producing steam. Atomic fuels such as uranium or thorium may also be used to produce steam. When conventional type of fuels such s coal, oil, etc. (called fossils ) is used to produce steam for running the turbines, the power house is generally called an Ordinary thermal power station or Thermal power station. But when atomic fuel is used to produce steam, the power station, which is essentially a thermal power station, is called an atomic power station or nuclear power station. In an ordinary thermal power station, steam is produced in a water boiler, while in the atomic power station; the boiler is replaced y a nuclear reactor and steam generator for raising steam. The electric power generated in both these cases is known as thermal power and the scheme is called thermal power scheme.But, when the energy of the flowing water is used to run the turbines, then the electricity generated is called hydroelectric power. This scheme is known as hydro scheme, and the power house is known as hydel power station or hydroelectric power station. In a hydro scheme, a certain quantity of water at a certain potential head is essentially made to flow through the turbines. The head causing flow runs the turbine blades, and thus producing electricity from the generator coupled to turbine. In this chapter, we are concerned with hydel scheme only.2 classification of hydel plantsHydro-plants may be classified on the basis of hydraulic characteristics as follow: ①run-off river plants ; ②storage plants ; ③pumped storage plants ; ④tidal plants. they are described below:(1)Run-off river plants.These plants are those which utilize the minimum flow in a river having no appreciable pondage on its upstream side. A weir or a barrage is sometimes constructed across a river simply to raise and maintain the water level at apre-determined level within narrow limits of fluctuations, either solely for the power plants or for some other purpose where the power plant may be incidental. Such a scheme is essentially a low head scheme and may be suitable only on a perennial river having sufficient dry weather flow of such a magnitude as to make the development worthwhile.Run-off river plants generally have a very limited storage capacity, and can use water only when it comes. This small storage capacity is provided for meeting the hourly fluctuations of load. When the available discharge at site is more than the demand (during off-peak hours ) the excess water is temporarily stored in the pond on the upstream side of the barrage, which is then utilized during the peak hours.he various examples of run-off the river pant are: Ganguwal and Kolta power houses located on Nangal Hydel Channel, Mohammad Pur and Pathri power houses on Ganga Canal and Sarda power house on Sarda Canal.The various stations constructed on irrigation channels at the sites of falls, also fall under this category of plants.(2) Storage plantsA storage plant is essentially having an upstream storage reservoir of sufficient size so as to permit, sufficient carryover storage from the monsoon season to the dry summer season, and thus to develop a firm flow substantially more than minimum natural flow. In this scheme, a dam is constructed across the river and the power house may be located at the foot of the dam such as in Bhakra, Hirakud, Rihand projects etc. the power house may sometimes be located much away from the dam (on the downstream side). In such a case, the power house is located at the end of tunnels which carry water from the reservoir. The tunnels are connected to the power house machines by means of pressure pen-stocks which may either be underground (as in Mainthon and Koyna projects) or may be kept exposed (as in Kundah project).When the power house is located near the dam, as is generally done in the low head installations ; it is known as concentrated fall hydroelectric development. But when the water is carried to the power house at a considerable distance from the dam through a canal, tunnel, or pen-stock; it is known as a divided fall development.(3) Pumped storage plants.A pumped storage plant generates power during peak hours, but during theoff-peak hours, water is pumped back from the tail water pool to the headwater pool for future use. The pumps are run by some secondary power from some other plant in the system. The plant is thus primarily meant for assisting an existing thermal plant or some other hydel plant.During peak hours, the water flows from the reservoir to the turbine and electricity is generated. During off-peak hours, the excess power is available from some other plant, and is utilized for pumping water from the tail pool to the head pool, this minor plant thus supplements the power of another major plant. In such a scheme, the same water is utilized again and again and no water is wasted.For heads varying between 15m to 90m, reservoir pump turbines have been devised, which can function both as a turbine as well as a pump. Such reversible turbines can work at relatively high efficiencies and can help in reducing the cost of such a plant. Similarly, the same electrical machine can be used both as a generator as well as a motor by reversing the poles. The provision of such a scheme helps considerably in improving the load factor of the power system.(4) Tidal plantsTidal plants for generation of electric power are the recent and modern advancements, and essentially work on the principle that there is a rise in seawater during high tide period and a fall during the low ebb period. The water rises and falls twice a day; each fall cycle occupying about 12 hours and 25 minutes. The advantage of this rise and fall of water is taken in a tidal plant. In other words, the tidal range, i.e. the difference between high and low tide levels is utilized to generate power. This is accomplished by constructing a basin separated from the ocean by a partition wall and installing turbines in opening through this wall.Water passes from the ocean to the basin during high tides, and thus running the turbines and generating electric power. During low tide, the water from the basin runs back to ocean, which can also be utilized to generate electric power, provided special turbines which can generate power for either direction of flow are installed. Such plants are useful at places where tidal range is high. Rance power station in France is an example of this type of power station. The tidal range at this place is of the order of 11 meters. This power house contains 9 units of 38,000 kW.Hydro-plants or hydroelectric schemes may be classified on the basis of operating head on turbines as follows: ①low head scheme (head<15m); ②medium head scheme (head varies between 15m to 60 m) ③high head scheme (head>60m). They are described below:(1) Low head scheme.A low head scheme is one which uses water head of less than 15 meters or so. A run off river plant is essentially a low head scheme, a weir or a barrage is constructedto raise the water level, and the power house is constructed either in continuation with the barrage or at some distance downstream of the barrage, where water is taken to the power house through an intake canal.(2) Medium head schemeA medium head scheme is one which used water head varying between 15 to 60 meters or so. This scheme is thus essentially a dam reservoir scheme, although the dam height is mediocre. This scheme is having features somewhere between low had scheme and high head scheme.(3) High head scheme.A high head scheme is one which uses water head of more than 60m or so. A dam of sufficient height is, therefore, required to be constructed, so as to store water on the upstream side and to utilize this water throughout the year. High head schemes up to heights of 1,800 meters have been developed. The common examples of such a scheme are: Bhakra dam in (Punjab), Rihand dam in (U.P.), and Hoover dam in (U.S.A), etc.The naturally available high falls can also be developed for generating electric power. The common examples of such power developments are: Jog Falls in India, and Niagara Falls in U.S.A.水轮机1.概述水的能量可以通过三种基本方法来获得：利用水的重力作用、水的压力作用或水的流速作用，或者其中任意两种或全部三种作用的组合。
水利工程毕业设计外文翻译--三峡水利枢纽工程
附录一：外文翻译The Three Gorges ProjectsFirst. The dam site and basic pivot disposalThe Three Gorges Projects is select to be fixed on San Dou Ping in Yichang, located inabout 40 kilometers of the upper reaches of key water control project of Ge Zhou Ba which was built. River valley, district of dam site, is widen, slope, the two sidesof the bank is relatively gentlely. In the central plains have one island (island, fort of China,), possess the good phased construction water conservancy diversion condition. The foundation of pivot building is the hard and intact body of granite. Have built Yichang and gone to stride bridge that place of 4 kilometers in the about 28 -km-long special-purpose expressway of building site and dam low reaches --West Yangtze Bridge of imperial tomb. Have also built the quay of district of a batch of dams. The dam district possesses the good traffic condition.Two. Important water conservancy project buildings1. damThe dam is a concrete gravity dam, which is 2309 meters long, it’s height is 185 meters , the dam is 181 meters high the most. Release floodwater dam section lie riverbed, 483 of the total length, consist of 22 form hole and 23 release floodwater in the deep hole, among them deep hole is imported 90 meters , the mouth size of hole is 7*9 meters; Form hole mouth is 8 meter wide, overflow weir is 158 meters, form hole and deep hole adopt nose bank choose, flow way go on and can disappear. Dam section lies in and releases floodwater on a section of both sides of the dam in the hydropower station, there are hydropower stations that enter water mouth. Enter water mouth baseplate height 108 meters. Pressure input water pipeline for carry person who in charge of, interior diameter 12.40, adopt the armored concrete to receive the strength structure. Make and let out flow of 102500 cubic meters per second the most largely in the dam site while checking the flood.2. power stationsThe power stations adopt the type after the dam to assign the scheme, consist oftwo groups of factory buildings on left, right and underground factory building altogether. Install 32 sets of hydroelectric generating set together, 14 factory buildings of left bank among them, 12 factory buildings of right bank, 6 underground factory buildings. The hydraulic turbine, in order to mix the flowing type, the specified capacity of the unit of the unit is 700,000 kilowatts.3. open up to navigation buildingThe open up to navigation buildings include permanent lock and ship lift (of the the technological public relations, the steel cable that plans to be replaced with spiral pole technology in the original plan promotes technology), lie in the left bank. Permanent lock double-line five continuous chain of locks. Single grades of floodgate room effective size for 280*34*5, can pass the 10,000 ton-class fleet. The promoting type for single track first grade vertically of the ship lift is designed, it is 120*18*3.5 meters to bear the effective size of design of railway carriage or compartment of ship, can pass a combination vessel of 3000 tons once. Total weight is 11800 tons to bear the design of railway carriage or compartment of ship when operating, it is 6000 newtons to always promote strength.Three.The major project amount and arranges in time limit The subject building of the project and major project amount of the water conservancy diversion project are: Excavate 102,830,000 cubic meters in cubic metre of earth and stone, fill out and build 31,980,000 cubic meters in cubic metre of earth and stone, concrete builds 27,940,000 cubic meters, 463,000 tons of reinforcing bars, make and fit 32 with hydroelectric generating set. All project construction tasks were divided into three stages and finished, all time limit was 17 years. The first stage (1993-1997 year) is preparation of construction and the first stage of the project, it takes 5 years to construct, regard realizing damming in the great river as the sign. The second stage (1998-2003 year) is the second stage, it takes 6 years to construct, lock as initial conservation storage of the reservoir, the first batch of aircrews generate electricity and is open up to navigation with the permanent lock as. The third stage (2004-2009 year) is the third stage of the project, it takes 6 years to construct, regard realizing the sign all aircrews generate electricity and finish building with all of multi-purpose project as. One, two project finish as scheduled already, the third stageof the project in inside the plan to construct too, ship lift tackle key problems of not going on intensely.Four. Enormous benefit of the Three Gorges Projects The Three Gorges Projects is the greatest water control project in China ,also in the world , it is the key project in controlling and developing the Changjiang River. The normal water storage level of the Three Gorges Projects reservoir is 175 meters, installed capacity is 39,300 million cubic meters; The total length of the reservoir is more than 600 kilometers, width is 1.1 kilometers on average; The area of the reservoir is 1084 sq. km.. It has enormous comprehensive benefits such as preventing flood, generating electricity, shipping,etc..1. prevent floodPrimary goal of building the Three Gorges Projects is to prevent flood . The key water control project in Sanxia is the key project that the midstream and downstream of the Changjiang River prevent flood in the system. Regulated and stored by the reservoir of Sanxia, form the capacity of reservoir in the upper reaches as river type reservoir of 39,300 million cubic meters, can regulate storage capacity and reach 22,150 million cubic meters, can intercept the flood came above of Yichang effectively, cut down flood crest flow greatly, make Jingjiang section prevent flood standard meet, improve from at present a about over ten years to once-in-a-hundred-year. Meet millennium first special great flood that meet, can cooperate with Jingjiang flood diversion partition application of flood storage project, the crushing calamity of preventing the occurrence of both sides of section of Jingjiang and bursting in the main dike, lighten midstream and downstream losing and flood threat to Wuhan of big flood, and can create conditions for administration of Dongting Hu district.2. generates electricityThe most direct economic benefits of the Three Gorges Projects is to generate electricity . Equilibrate the contradiction that contemporary China develops economic and serious energy shortage at a high speed, the hydroelectric resources that a clean one can be regenerated are undoubtedly optimum choices. The total installed capacity of power station of Sanxia is 18,200,000 kilowatts, annual average generation is84,680 million kilowatt hours. It will offer the reliable, cheap, clean regenerated energy for areas such as East China, Central China and South China of economic development, energy deficiency,etc.It play a great role in economic development and environmental pollution of reducing.Electric power resource that the Three Gorges Projects offers, if given a workforce of electricity generation by thermal power, mean building 10 more thermal power plants of 1,800,000 kilowatts, excavate more 50 million tons of raw coals every year on average. Besides environment of influencing of the waste residue, it will also discharge a large number of carbon dioxide which form the global greenhouse effects every year, cause the sulfur dioxide of acid rain, poisonous gas carbon monoxide and nitrogen oxide. At the same time, it will also produce a large amount of floating dust, dustfall,etc… Thermal power plant and abandon dreg field extensive occupation of land seize more land from East China, Central China area that have a large population and a few land just originally this. This not only makes China bear the pressure that greater environment brings in the future, cause unfavorable influence on the global environment too.3. shippingSanxia reservoir improve Yichang go to Chongqing channel of the Changjiang River of 660 kilometers notably, the 10,000 ton-class fleet can go to the harbour of Chongqing directly. The channel can rise to 50 million tons from about 10 million tons at present through ability in one-way year, transporting the cost can be reduced by 35-37%. Unless until reservoir regulate, Yichang low water flows minimum seasons downstream,whose name is can since at present 3000 cubic meters /second improve until 5000 cubic meters per above second, the shipping condition get greater improvement too to enable the Changjiang River in low water season of midstream and downstream.Five.The questions in building the Three Gorges Projects1. silt issuethe Changjiang River Yichang Duan Nian amount of sand failed 530 million tons, silt the reservoir of Sanxia up. The reservoir blocks water level is 175 meters high, installed capacity is 39,300 millionm3 normally,its die water level is 145 meters, theminimum capacity of a reservoir is 17,200 million m3, storage capacity 22,100 million m3, the conservation storage regulates the capacity of reservoir 16,500 million m3. The operation scheme of the reservoir is: Limit height is 145 meters of water level, in flood season, meet flood adjust big under 56700m3 per second, and power station smooth to let out through deep hole over 3 years, can reduce the sand of the reservoir to deposit. Great flood comes, the reservoir is adjusted bigly, still put and let out 56700m3per second; Deposit towards the reservoir after the flood. The reservoir begins conservation storage, between about two months and normal water storage level 175 meters high in September. The water level of the storehouse is dropped to 155 meters high before the flood next year, utilize conservation storage to generate electricity. In 155 meters water level, can keep the river shipping of Sichuan. By flood season, the water level was dropped to 145 meters water level again, because the flow was large at that time, could keep the river shipping of Sichuan. This is a reservoir operation scheme of innovation.2. question that the slope comes down by the bank of reservoir areaThe question that the slope comes down is through detailed geological survey by 2 reservoir area banks, there is several to come down potentially on water bank of Kuku of Sanxia, the big one can be up to millions of m3. But closest to dam site potential landslide, too far on 26kilometers, such as happen, come down, shock wave that evoke get dam disappear, reduce 2-3meters to to be high, it is safe not to influence the dam. In addition, if the slippery wave happens in the bank of the storehouse, because the reservoir is wide and deep, will not influence shipping.3. engineering question of the pivotThe pivotof Three Gorges is 185 meters high concrete gravity dampivots and 18,200,000kW, the project amount is large, but all regular projects after all, our country has more experience. The stability problem of some foundation can meet the safe requirement through dealing with. 700,000kW hydroelectric generating set, imported from foreign countries in the first batch, was made by oneself at home later. The more complicated one is lock of five grades of Line two, deep-cut in the rock bank, slope reaches 170 meters at the supreme side, the underpart floodgate room vertical 60 meters, high rock slope stability worries about. But the meticulousresearch of engineer and constructors is designed, blown up and the anchor is firm and excavating, the rock slope is steady in a long-term. There is ship lift of 3000t passenger steamer, it is the biggest in the world, in course of designing and studying, and repair the test and use the ship lift first.4.ecological environment problemThe respect useful to ecological environment of the Three Gorges Projects is: Prevent and cure downstream land and cities and towns to flood, reduce the air pollution of electricity generation by thermal power, improve some climate, the reservoir can breed fish etc.. The respect disadvantageous to ecology is: Flood more than 300,000 mu of cultivated land, ground of fruit is more than 200,000 mu, immigrants reach the highland by the storehouse, will destroy the ecological environment, the still water weakens the sewage self-purification ability, worsen water quality, influence reproduction of the wild animal,etc. in the reservoir. So is both advantageous and disadvantageous, do not hinder building the Three Gorges Projects. Should reduce being unfavorable to minimum extent, it is mainly that reservoir immigrants want to plant trees and grass, build the terraced fields, ecological environment protection, does not require the self-sufficiency of grain. Accomplish these, want making a great effort and fund. Control blowdown such as Chongqing, Fuling, Wan County, carry on sewage disposal, protect the water quality of the reservoir, protect the wild animal, set up the protection zone. Although ecological environment protection is difficult, must solve and can solve. As for the scenery of Sanxia, because the high near kilometer of rock bank, and Sanxia dam is only in fact higher than the river surface 110 meters. The scenery basically remains unchanged, the high gorge produces Pinghu, increase even more beautifully.Six. Immigrant's question in the reservoir areaThe reservoir of Sanxia will flood 632 sq. km. of land area, will involve Chongqing, 20 county (market) of Hubei. The reservoir of Sanxia floods and involves 2 cities, 11 county towns, 116 market towns; Flood or flood 1599 of industrial and mining enterprises that influence, reservoir flood line there are 24,500 hectares of cultivated land in all; Flood 824.25 kilometers of highways, 92,200 kilowatts of power stations; The area of house of flooding area is 34,596,000 square meters, totalpopulation of living in the flooding area is 844,100 people (agricultural population 361,500 people among them). Consider population growth and other factors of moving etc. two times during construction, the total population of trends of reservoir immigration allocation of Sanxia will be up to 1,130,000 people. The task is arduous, but must find a room for good immigrants, make its life improve to some extent, help immigrants to create the working condition, live plainly and struggle hard through 20 years, grow rich. Most immigrants retreat to the highland, it is nonlocal that some immigrants get. The reservoir of Sanxia will flood 632 sq. km. of land area, will involve Chongqing, 20 county (market) of Hubei. The reservoir of Sanxia floods and involves 2 cities, 11 county towns, 116 market towns; Flood or flood 1599 of industrial and mining enterprises that influence, reservoir flood line own cultivated land (suck the ground of mandarin orange) 24,500 hectares in common; Flood 824.25 kilometers of highways, 92,200 kilowatts of power stations; The area of house of flooding area is 34,596,000 square meters, The total population of living in the flooding area is 844,100 people (agricultural population 361,500 people among them). Consider population growth and other factors of moving etc. two times during construction, the total population of trends of reservoir immigration allocation of Sanxia will be up to 1,130,000 people.1.exploration and opening of the immigrants in SanxiaThe exploration of an immigrant in Sanxia and open country are in the engineering construction of Sanxia, implement immigrant's policy of the exploration, relevant people's governments organize and lead immigrants to arrange work, use immigrant's funds in a unified manner, exploit natural resources rationally, based on agriculture, the agriculture,industry and commerce combine, through many channel, many industries, multi-form, many method find a room for immigrants properly, immigrants' living standard reach or exceed originally and competently, and create the condition for long-term economic development and improvement of immigrant's living standard of reservoir area of Three Gorges. Immigrant's policy of the exploration, is a great reform of the reservoir immigrants of our country. Policy this, and reservoir area of Three Gorges immigrant put forward at the foundation of pilot project eight year in experience and lessons that immigrant work since new China setup of summarizing. At the beginning of reservoir immigrants in Sanxia, carry out exploration immigrants' principles and policies, insist the country supports, the policy is favourable, each side supports, principle of relying on one's own efforts, appeared by the government, develop local resources in a planned way, expand the capacity of placing, help, offer service of forming a complete set, wide to open up, produce the life way, make it reach " take out offing, goal that so steady as to live, can get rich progressively ". Meanwhile, the country approves reservoir area of Three Gorges as " the open economic region of Sanxia ", enjoy some special policies opening to the outside world in the coastal area, call the immigrants in Sanxia of the developed coordinated cooperation of province and city, immigrant's enterprises and relevant The factor of production has been pushed to the broader large market. The governments at all levels of reservoir area of Three Gorges have issued some development coordinated cooperation, favourable measure inviting outside investment too. Reservoir area immigrant demonstrate with open to urge, develop, in order to develop, urge benign situation that place.2. reorganization and expansion of the immigrants in SanxiaThe reorganization of immigrants in Sanxia and the expansion immigrants in Sanxia are that one involve undertaking that the society of reservoir area reconstruct, resources are recombinated, the recombinating is one of the prominent characteristics of the immigrants in Sanxia, move the fundamental difference duplicated with traditional simple compensation immigrants, former state too. Implement immigrant's policy of the exploration, must demand to combine immigrants to move, reconfigure the factor of production, thus improve the disposition efficiency of resources, form new productivity. Expand while being what is called, expansion of scale, improvement of structure even more, function strengthen improvement of quality. Look with the view of development economics and implement the course of exploration immigrants, it is the course of economic expansion of reservoir area. Exploration immigrants begin from expanding, and ending at realizing expanding, the course that the whole immigrant move and rebuild one's home is running through economic expansion, full of to the yearning that expands in the future. Certainly, in actual operation, should set out from immigrant's reality to pay attention to all, insistreason is expanded.Seven. Investment and benefit questionInvests 90,090 million yuan (1993 price) in investment and the Three Gorges Projects static behavior of benefit question, invests more than about 200 billion yuan dynamically while finishing in project. The investment source of the Three Gorges Projects is as follows, state loan, state-run hydropower station each of price of electricity raise the price 0.4-0.7 fen, power station electric rate income of Ge Zhou Ba, the electric rate income after the power station of Sanxia generates electricity wait for, the country has this financial resources to guarantee to invest in putting in place. About benefit, it is estimated it in ten years after the Three Gorges Projects is built up, total project investment principal and interest, unless including project fee and fee for immigration, can have repaid with electric rate income,it prevent flood, shipping,etc. share make the investment. And the Three Gorges Projects prevent flood, generate electricity, shipping,etc. benefit long-term, and enormous social benefit. Therefore, benefit of the Three Gorges Projects is very great, there is increase slightly to even make the investment, it is very rational too to repay service life to slightly lengthen.三峡水利枢纽工程一、坝址及基本枢纽布置三峡工程大坝坝址选定在宜昌市三斗坪，在已建成的葛洲坝水利枢纽上游约40km处。
水利水电专业毕业论文文献翻译中英文对照[管理资料]
![水利水电专业毕业论文文献翻译中英文对照[管理资料]](https://img.taocdn.com/s3/m/63ee21d74b35eefdc9d33334.png)
DamThe first dam for which there are reliable records was build or the Nile River sometime before 4000 . It was used to divert the Nile and provide a site for the ancient city of Memphis .The oldest dam still in use is the Almanza Dam in Spain, which was constructed in the sixteenth century. With the passage of time,materials and methods of construction have improved. Making possible the erection of such large dams as the Nurek Dam, which is being constructed in the . on the vaksh River near the border of Afghanistan. This dam will be 1017ft(333m) high, of earth and rock fill. The failure of a dam may cause serious loss of life and property; consequently, the design and maintenance of dams are commonly under government surveillance. In the United States over 30,000 dams are under the control of state authorities. The 1972 Federal Dams Safety Act (PL92-367)requires periodic inspections of dams by qualified experts. The failure of the Teton Dam in Idaho in June 1976 added to the concern for dam safety in the United States.1 Type of DamsDams are classified on the type and materials of construction, as gravity, arch, buttress ,and earth .The first three types are usually constructed of concrete. A gravity dam depends on its own weight for stability and it usually straight in plan although sometimes slightly curved.Arch dams transmit most of the horizontal thrust of the water behind them to the abutments by arch action and have thinner cross sections than comparable gravity dams. Arch dams can be used only in narrow canyons where the walls are capable of withstanding the thrust produced by the arch action. The simplest of the many types of buttress dams is the slab type, which consists of sloping flat slabs supported at intervals by buttresses. Earth dams are embankments of rock or earth with provision for controlling seepage by means of dam may be included in a single structure. Curved dams may combine both gravity and arch action to achieve stability. Long dams often have a concrete river section containing spillway and sluice gates and earth or rock-fill wing dams for the remainder of their length.The selection of the best type of dam for a given site is a problem in both engineering feasibility and cost. Feasibility is governed by topography, geology and climate. For example, because concrete spalls when subjected to alternate freezing and thawing, arch and buttress dams with thin concrete section are sometimes avoided in areas subject to extreme cold. The relative cost of the various types of dams depends mainly on the availability of construction materials near the site and the accessibility of transportation facilities. Dams are sometimes built in stages with the second or late stages constructed a decade or longer after the first stage.The height of a dam is defined as the difference in elevation between the roadway, or spillway crest, and the lowest part of the excavated foundation. However, figures quoted for heights of dams are often determined in other ways. Frequently the height is taken as the net height is taken as the net height above the old riverbed.on damsA dam must be relatively impervious to water and capable of resisting the forces acting on it. The most important of these forces are gravity (weight of dam) , hydrostatic pressure, uplift, ice pressure, and earthquake forces are transmitted to the foundation and abutments of the dam, which react against the dam with an equal and opposite force, the foundation reaction. The effect of hydrostatic forces caused by water flowing over the dam may require consideration in special cases.The weight of a dam is the product of its volume and the specific weight of the material. The line of action of dynamic force passes through the center of mass of the cross section. Hydrostatic force may act on both the upstream and downstream faces of the dam. The horizontal componentH of the hydrostatic force is the force or unit width of damhit is2/2HrhhWhere r is the specific weight of water and h is the depth of water .The line of action of this force is h/3 above the base of thedam .The vertical component of the hydrostatic force is equal to the weigh of water vertically above the face of the dam and passes through the center of gravity of this volume of water.Water under pressure inevitably finds its way between the dam And its foundation and creates uplift pressures. The magnitude of the uplift force depends on the character of the foundation and the construction methods. It is often assumed that the uplift pressure varies linearly from full hydrostatic pressure at the upstream face (heel)to full tail-water pressure at the downstream face (toe).For this assumption the uplift force U isU=r(h1+h2)t/2Where t is the base thickness of the dam and h1and h2 are the water depths at the heel and toe of the dam,respectively. The uplift force will act through the center of area of the pressure trapezoid.Actual measurements on dams indicate that the uplift force is much less than that given by Eq.(2)Various assumption have been made regarding the distribution of uplift of Reclamation sometimes assumes that the uplift pressure on gravity dams varies linearly from two-thirds of full uplift at the heel to zero at the toe. Drains are usually provided near the heel of the dam to permit the escape of seepage water and relieve uplift.译文：坝据可靠记载，世界上第一座坝是公元前4000年以前在尼罗河上修建的。
水电站初步设计大学毕业论文英文文献翻译及原文
毕业设计（论文）外文文献翻译文献、资料中文题目：水电站初步设计文献、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：班级：姓名：学号：指导教师：翻译日期： 2017.02.14Elements of electrical power station design = 电站设计基础/ M. V. Deshp ande. ─ Wheeler Publishing, 1981Where water resources are available, hydro-electrie power station are used to supply electrical energy to consumers.This type of station，however, cannot be located everywhere. First,there must be an ample quantity of water at sufficient hard, and suitable site must be available.Stream flow date for a number of years should be studied.The possibility of constructing a dam at a suitable site to store water in the catchment area and the availability of water throughout the year are decisive factors. The amount of power that can be developed depends on the quantity of water available,the rate at which it is available,the head,etc.Hydro-electric projects involve a large amount of civil engineering construction work .Often the project is a multipurpose one embracing irrigation and power,flood control and power,or flood control,navigation and power.One might imagine that hydro-electric power should be very cheap as water does not cost anything and there is no fuel cost,This ,however,is not true.To store water at enough head,it is necessary to have a dam and civil engineering construction works. This costs money,and increases investment costs and fixed costs which are not required for other types of power plants,Whenever a hydro-electric project is considered for power purposes ,it is always necessary to work out the economics comparing hydro-electric power costs with the costs for other forms of station.7.2HydrologyWhen considering the possibility of a hydro-electric project,the first requirement is to obtain data regarding the stream flow of water that would be available,and to predict the yearly possible flow from the data ,The water cycle in general consists of evaporation from seas or oceans and/or other water surfaces on the earth due to heat from the sun,the formation of moist air and clouds ,the circulation in form of rain ,hail or snow .Determination of the amount of stream flow and its variation involves a study of hydrography (or hydrology) which deals with the occurrence and under the earth's surface.The science of hydrology is based on meteorology ,geology,agricultural physics,chemistry,botany and data obtained by observation and measurement.It is necessary to calculate the mean annual rainfall in the area under consideration from a record of the annual rainfall for a number of years,say 25to30,and also to note the frequency of dry years.The precipitation or rainfall in a particular area can be measured by rain gauges at various places in the area.A rain gauge consists of a collecting cylinder which exposes a circular gauge consists of a collecting cylinder which exposes a circular surface for collecting the rain and a storage vessel in which the water is retained until measured .Recording rain gauges ,giving a continuous record,are use where possible.Frequency of precipitation is also care fully noted.A curve of precipitation in millimetres plotted against percentage of time gives a range of able for a number of years,the range of distribution of mean monthly precipitation is obtained the general character of the periodic distribution of the rainfall tends to be similar each year in each locality .There is some variation in the occurrence of rainfall from year to year ,but when the record of a number of seasons is available ,it is usually found that the occurrences of rainfall for a given month in a given locality are similar.The frequency of occurrence of a dry year or two consecutive dry years is also seen when records for a long period are available.Precipitation in a particular locality depends to a certain extent on altitude,The general and fundamental tendency is for the precipitation to increase as the altitude increases on the coastalside of a mountain range,if the locality is not far from the general sources of water vapour.Date regarding maximum rainfall in a particular area and the nature of the drainage area help in the study of possible floods in the area.Knowledge of the frequency of high rainfall in the are is also helpful in the above studies.The mean precipitation on a drainage area over a period of time can be obtained by plotting isohyets,or lines of equal precipitation,from the records available and then finding a weighted average by planimeter.Of the total precipitation ,some part of the water is lost.Sources of loss are evaporation from the water are ,soil evaporation ,interception and transpiration losses from land area.The stream flow is known when the water losses have been subtracted from the precipitation .Stream flow consists of surface flow and percolation through the ground.The various factors which affect the distribution of precipitation are meteorological conditions, drainage area characteristics,topography of land,geology of land and vegetation in the area.Evaporation is effected by heat from the sun.Temperature and relative humidity affect evaporation,and so too does wind velocity.Plants absorb moisture from the ground,giving it off to the atmosphere,the process being known as transpiration.During the process ,some water is lost,this is known as transpiration loss.Drainge area characteristics are the size and shape of the are .A small area tends to have a higher unit flood discharge than a large area.The topography of land and surface slopes affects the surface flow of water.Steep slopes tend towards a rapid and large surface flow.The size of the water area affects the losses .A large percentage of water area tends to a diminished run-off.The geological characteristics of the watershed affect run-off. Evaporation varies inversely with the porosity of soil.Percolation and water losses depend on whetner the soil is pervious or impervious.A large surface run-off is experienced when pervious ground is saturated with rainwater or when the ground is of impervious material such as rock or clay.Evaporation and percolation are increased by cultivation.Transpiration and interception losses occur owing to the presence of vegetation.To find the evaporation from a water surface a shallow pan is partly immersed in a lake or reservoir ,the evaporation being measured by the change in the water level in the pan, If the pan were placed on land, the temperature would differ from that of the lake.Humidity and wind,air and water temperatures are noted because evaporation varies with all these factors.Transpiration is estimated in a particular area in an approximate,empirical way.Changes in ground water level are found by a water-level recorder.The amount of moisture in the soil above the water table is found by measuring the electrical resistance of gypsum blocks buried at different depths in the ground.The resistance of gypsum increases as it gets drier.The soil temperature is measured by means of thermocouples placed near the gypsum blocks.In considering the factors affecting losses,the stream flow and the run-off available are determined.A drainage area and profile map is prepared.This shows the length of the river,the size and shape of the watershed,tributaries,lakes,reservoirs,etc.The watershed or drainage area is sometimes called the catchment area with respect to precipitation.7.3Stream Flow :Hydrographs:Flow Duration CurvesFor water-power studies,it is essential to know the streamflow date,over a long period if available.Daily,weekly or monthly flow data for number of years at a site help in finding the average flow data for a number of years at a site help in finding the average flow and output power that are likely to be available from the stream flow.The head available is determined by surveying the site.The minimum or lowwater flow data help in estimating the firm power that will be available at the site .The maximum flow helps in estimating the floods and in designing the spillway.Estimating the stream flow helps in determining the capacity of storage reservoir for equalising the flow to a given minimum.Knowing the maximum stream flow conditions, it is possible to estimate the necessary capacity of a flood-control reservoir for limiting the discharge to a pre-determined maximum under all conditions except extreme floods.When studing stream flow in a river,it is necessary to find the depth of the river at various sections by river gauging.The depth of the river is measured by wading in shallow water,by wire weight gauge,etc.Measurement of discharge in open channels is done by the velocity-area method or by the flow of water over a weir of known dimensions. In the velocity-area method,the discharge is obtained as the sum of the products of partial cross-sectional areas of the flowing water by the respective measured velocities in such areas.The cross-sectional areas are found by measuring the width and depth at suitably spaced points to show the shape of the river bed ,and summation of the partial areas is computed from these measurement.Velocities in different areas are measured by float or current meters.Thee other method of computing the discharge is by observing the head on a weir and the known dimensions of the weir.The discharge ,or volume rate of flow ,Q,in cubic metres per second,is given byQ=CLh3/2Where L is the length of the weir in metres ,h is the head in metres,and C is a constant.For a sharp-crested weir ,C is 1.85 approximately.Hydrographs. When a river discharge has been measured ,a curve can be plotted showing discharge in cubic metres/second against time in hours.The curve is known as a hydrograph.The ordinates may be plotted in terms of the gauge height ,the number of cubic metres per second per square kilometre,the power in kilowatts that can be developed theoretically per metre of fall,or the energy in kilowatt-hours,days or weeks.A hydrograph shows the variation of flow with time.It will also indicate the power available from the stream at different times of the day or year.It is similar to the load curve used in the study of electrical power.Hydrographs help in noting the extremes of flow more readily than the inspection of tabular values of the discharge.Hydrographs are essential in studies of the effect of storage on flow.Flow duration curve. The flow duration curve is a very convenient form of hydrograph for determining the available power at the site.It indicates the daily ,weekly or monthly flows available as ordinates plotted against percentage of time.The flow is available,one can convert the cubic metres per second per week,or other unit of time.Knowing the head at which the flow is available,one can convert the cubic metres per second per weeks,or the discharge for the period,into power in kilowatts,so that the flow duration curve becomes the load duration curve for a hydro-electric plant .If storage is available at a site upstream from the power plant ,a flow duration curve as modified by the use of storage,will be necessary.Low water flow decides the primary power that can be developed.The flow duration curve alsoshows the possible heavy flood flow and the time during which it may occur .The data are useful in designing a spillway on the dam to allow flood water to escape from the reservoir.It is easy to convert a hydrograph into a flow duration curve.The following examples illustrate the plotting of a hydrograph and flow duration curve from the flow data in terms of discharge per week.7.5 Investigation of SitePreliminary investigations are made when selecting the site for a dam,The dam should be as close to the turbines as possible,and should have maximum size of pondage and the shortest length of conduit.The ideal site will be one where the dam will have the largest catchment area to store water at a high head,and yet be economical in construction.A general reconnaissance survey is first made from the air .Topographical mapping is then carried out by detailed surveying of the area,Geological studies are made.Methods of exploring the sub-surface are by digging pits ,shafts and/or tunnels,etc.Supplementary methods used are the measurement of electrical resistivity and seismic methods of prospecting.The electrical resistivity method depends on the difference between the resistivities of the ledge rock and the overburden.The seismic method requires the measurement of the ratio of propagation of waves caused by explosion and is dependent on the difference in the elastic properties of the ledge rock and the overburden.Other methods of investigating the geological properties of rock are wash borings,churn drilling,rotary core drilling and diamond drilling.Sub-surface explorations should be made ,and condition of soil mechanics helps a great deal in this respect.Ti is necessary to investigate the possibility and availability of construction materials in the neighbourhood,namely,earth,gravel,concrete aggregates,etc.Foundation conditions have to be studied.水电站：初步设计—I7.1介绍水电站建在有水资源的地方，用于向消费者提供电能。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
毕业设计水利水电工程英文文献翻译外文文献：hydraulicturbines and hydro-electric powerAbstractPower may be developed from water by three fundamental processes : by action of its weight, of its pressure, or of its velocity, or by a combination of any or all three. In modern practice the Pelton or impulse wheel is the only type which obtains power by a single process the action of one or more high-velocity jets. This type of wheel is usually found in high-head developments. Faraday had shown that when a coil is rotated in a magnetic field electricity is generated. Thus, in order to produce electrical energy, it is necessary that we should produce mechanical energy, which can be used to rotate the ‘coil’. The mechanical energy is produced by running a prime mover (known as turbine ) by the energy of fuels or flowing water. This mechanical power is converted into electrical power by electric generator which is directly coupled to the shaft of turbine and is thus run by turbine. The electrical power, which is consequently obtained at the terminals of thegenerator, is then transited to the area where it is to be used for doing work.he plant or machinery which is required to produce electricity (i.e. prime mover +electric generator) is collectively known as power plant. The building, in which the entire machinery along with other auxiliary units is installed, is known as power house.Keywords hydraulic turbines hydro-electric power classification of hydel plantshead schemeThere has been practically no increase in the efficiency of hydraulic turbines since about 1925, when maximum efficiencies reached 93% or more. As far as maximum efficiency is concerned, the hydraulic turbine has about reached the practicable limit of development. Nevertheless, in recent years, there has been a rapid and marked increase in the physical size and horsepower capacity of individual units.In addition, there has been considerable research into the cause and prevention of cavitation, which allows the advantages of higher specific speeds to be obtainedat higher heads than formerly were considered advisable. The net effect of this progress with larger units, higher specific speed, and simplification and improvements in design has been to retain for the hydraulic turbine the important place which it has long held at one of the most important prime movers.1. types of hydraulic turbinesHydraulic turbines may be grouped in two general classes: the impulse type which utilizes the kinetic energy of a high-velocity jet which acts upon only a small part of the circumference at any instant, and the reaction type which develops power from the combined action of pressure and velocity of the water that completely fills the runner and water passages. The reaction group is divided into two general types: the Francis, sometimes called the reaction type, and the propeller type. The propeller class is also further subdivided into the fixed-blade propeller type, and the adjustable-blade type of which the Kaplan is representative.1.1 impulse wheelsWith the impulse wheel the potential energy of thewater in the penstock is transformed into kinetic energy in a jet issuing from the orifice of a nozzle. This jet discharge freely into the atmosphere inside the wheel housing and strikes against the bowl-shaped buckets of the runner. At each revolution the bucket enters, passes through, and passes out of the jet, during which time it receives the full impact force of the jet. This produces a rapid hammer blow upon the bucket. At the same time the bucket is subjected to the centrifugal force tending to separate the bucket from its disk. On account of the stresses so produced and also the scouring effects of the water flowing over the working surface of the bowl, material of high quality of resistance against hydraulic wear and fatigue is required. Only for very low heads can cast iron be employed. Bronze and annealed cast steel are normally used.1.2 Francis runnersWith the Francis type the water enters from a casing or flume with a relatively low velocity, passes through guide vanes or gates located around the circumstance, and flows through the runner, from which it discharges into a draft tube sealed below the tail-water level. All therunner passages are completely filled with water, which acts upon the whole circumference of the runner. Only a portion of the power is derived from the dynamic action due to the velocity of the water, a large part of the power being obtained from the difference in pressure acting on the front and back of the runner buckets. The draft tube allows maximum utilization of the available head, both because of the suction created below the runner by the vertical column of water and because the outlet of he draft tube is larger than the throat just below the runner, thus utilizing a part of the kinetic energy of the water leaving the runner blades.1.3 propeller runnersnherently suitable for low-head developments, the propeller-type unit has effected marked economics within the range of head to which it is adapted. The higher speed of this type of turbine results in a lower-cost generator and somewhat smaller powerhouse substructure and superstructure. Propeller-type runners for low heads and small outputs are sometimes constructed of cast iron. For heads above 20 ft, they are made of cast steel, a much more reliable material. Large-diameter propellers。