NUMERICAL STUDY OF CAVITATION ON THE SURFACE OF THE GUIDE VANE IN THREE GORGES HYDROPOWER UNIT

作     者：PENG Yu-cheng CHEN Xi-yang CAO Yan HOU Guo-xiang PENG Yu-cheng, CHEN Xi-yang School of energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China CAO Yan College of Electronic Information Engineering, Wuhan Polytechnic, Wuhan, 430074, China HOU Guo-xiang School of Traffic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

作者机构：School of energy and Power Engineering Huazhong University of Science and Technology Wuhan 430074 China College of Electronic Information Engineering Wuhan Polytechnic Wuhan 430074 China School of Traffic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China 

出 版 物：《Journal of Hydrodynamics》 (水动力学研究与进展B辑（英文版）)

年 卷 期：2010年第22卷第5期

页      面：703-708页

核心收录：

学科分类：080703[工学-动力机械及工程] 080704[工学-流体机械及工程] 07[理学] 08[工学] 070601[理学-气象学] 0807[工学-动力工程及工程热物理] 0706[理学-大气科学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 50975103 and 51006039) 

主　　题：cavitation guide vane numerical analysis 

摘      要：Large-area erosions such as rust and obvious cavitation were found on the surface of the guide vane in Three Gorges hydropower units. A numerical explanation of the cavitation is given in this article. At first, based on the characteristic performance curves of the prototype hydro-turbine supplied by ALSTOM together with the actual operating conditions, an operating point is chosen for numerical analysis using the Reynolds-Averaged Navier-Stokes （RANS） equations. The flow passages from the inlet of the spiral case to the outlet of the draft tube are included in the computational domain. The results show that the static pressure on the guide vane surface is much higher than the critical pressure of cavitation. Secondly, a tiny protrusion on the guide vane surface is considered and the problem is simplified to a 2-D problem to study the local detailed flow near the guide vane surface. The protrusion is 0.5 mm in height and is 5.0 mm in width. On the basis of the results of RANS simulations, the 2-D problem is studied using the Large Eddy Simulation （LES）. It is shown that there exists a region in which the static pressure reaches a level below the vapor pressure of the water. Thirdly, a cavitation model is included for the 0.5 mm protrusion case and another tiny pit case, with a tiny pit 0.3 mm in depth and 1.0 mm in width. The results show that vapor bubble exists at the protrusion entrance and the pit exit as the low pressure regions.