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针对三峡工程水轮机的运行特点，采用长江天然泥沙进行了三峡水轮机模型浑水试验研究，其目的是了解水流挟沙对三峡水轮机性能的影响、水轮机转轮内泥沙磨损部位及相对强度等，为真机防护及运行提供依据．试验在中国水利水电科学研究院水力机电研究所高精度水力机械通用模型浑水试验台上进行．试验内容包括清浑水能量试验、清浑水临界空化性能与初生空化性能试验、清浑水水压脉动试验和泥沙磨损试验．结果表明，在三峡水电站过机泥沙条件下，水流挟沙对水轮机效率、运行工况及水压脉动的影响很小，而对初生空化影响比较大，即随着含沙量的增大，初生空化系数有增大的趋势．此外，为减轻磨损，汛期浑水工况下水轮机应尽量避免过大开度或超负荷运行，转轮抗磨防护重点部位为叶片出水边和下环内侧面．
According to the operational characteristics of the Three Gorges Turbines, the Yangtze River natural sediment was used to test the turbid water of the Three Gorges Turbine Model. The purpose was to understand the influence of sediment flow on the performance of the Three Gorges turbines, the erosion site and the relative intensity of sediment in the turbine runner, To provide a basis for real machine protection and operation. The experiment was carried out on the muddy water test bench of the high-precision hydraulic machinery general model of China Institute of Water Resources and Hydropower Research. The tests include clear water turbid water energy test, clear turbid water critical cavitation performance and primary cavitation performance test, clear turbid water pressure pulsation test and sediment abrasion test. The results show that under the conditions of overlying silt and sediment in the Three Gorges Hydropower Station, the influence of sediment flow on turbine efficiency, operating conditions and water pressure pulsation is small, but the impact on the primary cavitation is relatively large. With the increase of sediment concentration , The primary cavitation coefficient has an increasing trend. In addition, in order to reduce the wear and tear, turbines in flood season muddy water conditions should try to avoid excessive opening or overload operation, wheel anti-wear protection key parts of the blade out of water and the inner side of the ring.