【摘要】 多泥沙河流水电站中泥沙磨损问题是影响水轮机组安全运行中亟需解决的关键难题。本文提出匹配转轮叶型与水流来流、出流角度及沙粒冲击角度的抗磨优化方法。采用含沙多相流数值模拟技术对某一混流式水轮机的转轮、顶盖、底环等关键部件开展抗磨损优化设计研究，并对100%负荷下优化方案的机组性能进行全面评估。新转轮机组压力脉动幅值均低于原转轮，最大幅值降幅为7.3%。优化后转轮和顶盖轴向水推力及转轮径向力相对于原方案的变化幅度分别为2.76%、0.38%和16%，优化后机组径向轴承和推力轴承均可安全运行。优化前后转轮空化性能基本一致，叶片出水边均存在轻微初生空化，转轮不会发生严重的空蚀破坏;新转轮0节径模态(0ND)和5ND模态的固有频率与典型激励频率166.7倍转频的偏差均大于5%。原转轮和新转轮的最大应力均超过材料屈服极限。优化后机组各项指标均满足运行的安全要求，研究成果可为水电机组抗磨损问题提供技术指导，具有较高的推广应用价值和工程意义。更多还原

【Abstract】 The problem of sediment erosion in sediment laden water flow hydropower stations is a key challenge that urgently needs to be addressed in ensuring the safe operation of hydraulic turbine units.This paper proposes an anti-wear optimization method that matches the runner blade shape with the inflow and outflow angles of the water flow,as well as the angle of sand particle impact. Using numerical simulation technology of multiphase flow with sand content,the anti-wear optimization design of key components such as the runner,top cover,and bottom ring of a Francis turbine was studied,and the performance of the optimized unit under 100% load was comprehensively evaluated.The pressure pulsation amplitude of the new turbine unit is lower than that of the original turbine,with a maximum amplitude increase of 7. 3%. The changes in axial water thrust and radial force of the optimized runner and top cover compared to the original scheme are 2. 76%,0. 38%,and 16%,respectively. The optimized radial bearings and thrust bearings of the unit can operate safely. The cavitation performance of the runner before and after optimization is basically the same,with slight initial cavitation at the blade outlet,and the runner will not undergo serious cavitation damage. The difference between the natural frequencies of the 0 ND and 5 ND modes of the new wheel and the typical excitation frequency of 166. 7 times the rotational frequency is over 5%. The maximum stress of both the original and new runner exceeds the yield limit of the material. After optimization,all indicators of the unit meet the safety requirements for operation. The research results can provide guidance for the wear resistance of hydropower units,and have high promotion and application value and significance.更多还原