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数据驱动的水泵水轮机综合特性曲线优化表达

水利发展研究 2024年第6期24卷 65-72页

作者：张方芳陶然肖若富中国农业大学水利与土木工程学院北京100083 北京市供水管网系统安全节能技术工程研究中心北京100083

基于一水泵水轮机的水轮机工况综合特性曲线,文章旨在提出一种数据驱动的三维综合特性曲线表达方法,并提出遗传模糊算法用于寻找最优运行点,基于文章所提出的方法,单位流量、单位转速、效率、导叶开度等关系得到了直观清晰的表达,最优... 详细信息

基于一水泵水轮机的水轮机工况综合特性曲线,文章旨在提出一种数据驱动的三维综合特性曲线表达方法,并提出遗传模糊算法用于寻找最优运行点,基于文章所提出的方法,单位流量、单位转速、效率、导叶开度等关系得到了直观清晰的表达,最优运行范围也得到了有效确认,对电站高效运行、提高经济效益具有参考意义。

关键词：数据驱动水泵水轮机综合特性曲线遗传算法模糊逻辑

Analysis of the Pump-turbine S Characteristics Using the Detached Eddy Simulation Method

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 115-122页

作者： SUN Hui xiao ruofu WANG Fujun xiao Yexiang LIU Weichao College of Water Resources and Civil Engineering China Agricultural University State Key Laboratory of Hydroscience and Engineering & Department of Thermal Engineering Tsinghua University Dongfang Electric Machinery Co. Ltd

Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-turbine operation along the S-shaped curve can lead to difficulties during load rejection with unusual increases in the water pressure, which leads to machine vibrations. This paper describes both model tests and numerical simulations. A reduced scale model of a low specific speed pump-turbine was used for the performance tests, with comparisons to computational fluid dynamics（CFD） results. Predictions using the detached eddy simulation（DES） turbulence model, which is a combined Reynolds averaged Naviers-Stokes（RANS） and large eddy simulation（LES） model, are compared with the two-equation turbulence mode results. The external characteristics as well as the internal flow are for various guide vane openings to understand the unsteady flow along the so called S characteristics of a pump-turbine. Comparison of the experimental data with the CFD results for various conditions and times shows that DES model gives better agreement with experimental data than the two-equation turbulence model. For low flow conditions, the centrifugal forces and the large incident angle create large vortices between the guide vanes and the runner inlet in the runner passage, which is the main factor leading to the S-shaped characteristics. The turbulence model used here gives more accurate simulations of the internal flow characteristics of the pump-turbine and a more detailed force analysis which shows the mechanisms controlling of the S characteristics.

关键词： pump-turbine S-shaped characteristics detached eddy simulation(DES) numerical analysis

Effect of leading edge roughness on cavitation inception and development on thin hydrofoil

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排灌机械工程学报 2017年第11期35卷 921-926,940页

作者： TAO Ran xiao ruofu FARHAT Mohamed Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Net- work System China Agricultural University Beijing 100083 China Laboratory for Hydraulic Ma- chines Ecole Polyteehnique Federale de Lausanne Lausanne 1007 Switzerland

The cavitation incipience and development of water flow over a thin hydrofoil placed in the test section of high-speed cavitation tunnel were *** with smooth and rough leading edge were tested for different upstream velocities and incidence *** observations clearly revealed that cavitation incipience is enhanced by roughness at incidence angle below 2°.This is in line with the former reports,according to whose roughness element decreases the wettability and traps a larger amount of *** a result,surface nucleation is enhanced with an increased risk of ***,for higher incidence angles(>3°),it was found that cavitation incipience is significantly delayed by roughness while developed cavitation is almost the same for both smooth and rough *** unexpected incipience delay is related to the change in the boundary layer structure due to *** was also reported a significant influence of roughness on the dynamic of developed cavitation and shedding of transient cavities.

关键词： cavitation inception surface roughness sheet cavitation cloud cavitation hydrofoil

A general alternate loading technique and its applications in the inverse designs of centrifugal and mixed-flow pump impellers

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Science China(Technological Sciences) 2021年第4期64卷 898-918页

作者： WANG ChaoYue WANG FuJun AN DongSen YAO ZhiFeng xiao ruofu LU Li HE ChengLian ZOU ZhiChao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China China Institute of Water Resources and Hydropower Research Beijing 100038China China Water Resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

For the inverse designs of centrifugal and mixed-flow pump impellers,clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller *** this paper,to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller,a simple kinematic equation is derived based on the ideal assumptions,which indicates that the potential rothalpy gradient(PRG)is the most important dynamic source that actively induces secondary vortical *** by the natural adverse PRG on the S1 and S2 stream surfaces,two typical secondary flows,H-S and P-S secondary flows,are clearly *** specially suppress these typical secondary flows,a general alternate loading technique(GALT)is proposed,aiming to adjust the real blade loadingδp to control the PRG *** the blade fore part,theδp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 *** the blade middle part,theδp should be moderately decreased to reduce adverse streamwise PRG on the S1 *** the blade aft part,the difference in theδp between the shroud and hub streamlines should be decreased faster to control the exit *** applying the GALT to the impeller designs of three typical pump types in hydraulic engineering,the organizational effect of the PRG on fundamental flow structures is *** GALT can effectively control the PRG distributions and suppress the secondary flows,thereby widening the pump’s high-efficiency zone,improving flow uniformity and suppressing pressure *** with the current Z-G method and the ALT,the GALT can meet the requirements of"de-experience"better,thereby enabling the designers to obtain good products explicitly and quickly.

关键词： alternate loading technique inverse design centrifugal pump mixed-flow pump impeller potential rothalpy gradient

Optimization of Blade Geometry of Savonius Hydrokinetic Turbine Based onGenetic Algorithm

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Energy Engineering 2023年第12期120卷 2819-2837页

作者： Jiahao Lu Fangfang Zhang Weilong Guang Yanzhao Wu Ran Tao xiaoqin Li ruofu xiao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

Savonius hydrokinetic turbine is a kind of turbine set which is suitable for low-velocity *** conventional turbines,Savonius turbines employ S-shaped blades and have simple internal ***,there is a large space for optimizing the blade *** this study,computational fluid dynamics(CFD)numerical simulation and genetic algorithm(GA)were used for the optimal *** optimization strategies and methods were determined by comparing the results calculated by CFD with the experimental *** weighted objective function was constructed with the maximum power coefficient Cp and the high-power coefficient range R under multiple working *** helps to find the optimal individual of the objective *** the optimal scheme with the initial scheme,the overlap ratioβincreased from 0.2 to 0.202,and the clearance ratioεincreased from 0 to 0.179,the blade circumferential angleγincreased from 0°to 27°,the blade shape extended more towards the *** overall power of Savonius turbines was maintained at a high level over 22%,R also increased from 0.73 to *** comparison with the initial scheme,the energy loss of the optimal scheme at high blade tip speed is greatly reduced,and this reduction is closely related to the optimization of blade *** R becomes larger,Savonius turbines can adapt to the overall working conditions and meet the needs of its work in low flow rate *** results of this paper can be used as a reference for the hydrodynamic optimization of Savonius turbine runners.

关键词： Hydrokinetic turbine savonius runner multiple target optimization genetic algorithm performance improvement

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基于组合优化策略的离心泵叶轮优化设计

清华大学学报（自然科学版） 2006年第5期46卷 700-703页

作者：肖若富王正伟清华大学热能工程系北京100084

为了缩短水力机械的水力设计周期和提高设计效率,提出了一种水力机械全三维的优化设计体系,实现了叶片参数化设计、网格划分、CFD计算和后处理的过程全自动集成。采用了遗传算法(GA)全局探索、响应面(RSM)近似建模和二次序列规划方法(S... 详细信息

为了缩短水力机械的水力设计周期和提高设计效率,提出了一种水力机械全三维的优化设计体系,实现了叶片参数化设计、网格划分、CFD计算和后处理的过程全自动集成。采用了遗传算法(GA)全局探索、响应面(RSM)近似建模和二次序列规划方法(SQP)局部寻优的二阶组合优化策略,达到了高效优化设计水力机械叶轮的目的。利用该优化设计平台,以离心泵叶轮水力效率最大化为目标函数,以影响叶片形状的多个几何参数为设计变量,对离心泵叶轮进行了优化设计。优化设计后叶轮水力效率由原来的89.8%提高到92.4%。

关键词：水力机械水力设计离心泵优化

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双吸离心泵蜗壳面积比对水力性能的影响研究

农业机械学报 2018年第1期49卷 123-129页

作者：朱迪肖若富田芳中国农业大学水利与土木工程学院北京100083 中国农业大学北京市供水管网系统安全与节能工程技术研究中心北京100083

双吸离心泵具有流量大、扬程高的特点,被广泛应用于农业输水灌溉等工程。双吸泵的蜗壳和叶轮间具有动静干涉作用,两者之间的匹配形式会对水泵的水力性能产生影响。将CFD数值模拟和已有试验数据相结合,通过研究不同比转数的双吸离心泵蜗... 详细信息

双吸离心泵具有流量大、扬程高的特点,被广泛应用于农业输水灌溉等工程。双吸泵的蜗壳和叶轮间具有动静干涉作用,两者之间的匹配形式会对水泵的水力性能产生影响。将CFD数值模拟和已有试验数据相结合,通过研究不同比转数的双吸离心泵蜗壳面积比对水力性能的影响,得出不同比转数下双吸离心泵最优蜗壳面积比规律。研究发现,当蜗壳面积比在原有基础上增加时,其最高效率点向大流量工况偏移,且扬程和效率有下降的趋势,设计工况附近的平均效率降低;当蜗壳面积比减小时,其在一定范围内扬程和效率均出现上升,最高效率点偏向于小流量工况,但是当降低到一定程度时,扬程和效率均会出现急剧的下降,最终通过总结各个比转数双吸泵的最优蜗壳面积比,得到随着比转数的增加,最优蜗壳面积比增加,高效区范围逐渐加宽这一规律。

关键词：双吸离心泵蜗壳面积比水力性能数值模拟

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涡带工况下混流式水轮机转轮动应力特性分析

水力发电学报 2007年第4期26卷 130-134,140页

作者：肖若富王正伟罗永要清华大学热能工程系北京100084

近年来,国内一些大型混流式转轮出现了不同程度的裂纹问题,对机组安全运行构成了威胁。研究表明,水力激励引起的混流式水轮机转轮叶片动应力是引起叶片疲劳破坏的主要原因之一。文中首先对高水头小负荷的涡带工况下混流式水轮机内流场... 详细信息

近年来,国内一些大型混流式转轮出现了不同程度的裂纹问题,对机组安全运行构成了威胁。研究表明,水力激励引起的混流式水轮机转轮叶片动应力是引起叶片疲劳破坏的主要原因之一。文中首先对高水头小负荷的涡带工况下混流式水轮机内流场进行非定常CFD计算,得到涡带工况下叶片表面不同时刻的水压力载荷,并利用流固耦合方法对转轮进行结构场瞬态特性计算,分析转轮叶片的动应力特性。结果表明由于水压力脉动引起的转轮叶片上的振动交变动应力是混流式水轮机疲劳破坏的主要原因之一。计算结果可为其它水轮机转轮的动应力特性分析和疲劳分析提供参考。

关键词：水轮机流场计算流固耦合动应力特性

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混流泵叶轮反问题设计与水力性能优化

农业机械学报 2014年第9期45卷 84-88页

作者：肖若富陶然王维维杨魏中国农业大学水利与土木工程学院北京100083

基于三维反问题设计方法,结合CFD数值模拟,以混流泵叶片载荷分布参数为设计变量,以水力效率为优化目标,采用正交试验方法和响应面函数法建立设计变量与目标函数的关系,对混流泵进一步优化。分析了不同设计变量对目标函数的影响,发现叶... 详细信息

基于三维反问题设计方法,结合CFD数值模拟,以混流泵叶片载荷分布参数为设计变量,以水力效率为优化目标,采用正交试验方法和响应面函数法建立设计变量与目标函数的关系,对混流泵进一步优化。分析了不同设计变量对目标函数的影响,发现叶轮轮盘进口处载荷对泵的水力效率影响最明显。通过数值模拟对比基准叶轮与优化叶轮性能,优化后的混流泵模型最优工况下的水力效率提高3.2%,且水泵扬程基本保持不变,优化体系具有良好的工程应用价值。

关键词：混流泵反问题设计正交试验响应面法计算流体动力学