Abstract:The experiment on cavitation and cavitation erosion of pump and turbine with silt laden water as working medium was carried out. The experimental results show that lots of gas nuclei hiding in the gaps of sand surfaces grow up and form into the bubbles when pressure decreases, and then separate from the sand surface, cavitation happens finally. When sandiness and water temperature are constant, the cavitation pressure characteristics of silt laden water depend on three important factors, the local altitude, sand mass concentration and sand radius. When the former two factors are constant, the incipient cavitation and critical cavitation pressure both increase with the decrease of sand radius. The gas nuclei number of silt laden water is far greater than that of the clean water. When cavitation occurs in the silt laden water, the jet flow strength in sand water caused by the bubbles collapse is greater than that in the clean water. The two reasons above cause the cavitation damage of sediment laden flow in water pump and turbine stronger than that of the clean water in the same device conditions. At present, the mistake that the vapor pressure of clean water at zero altitude is used to be of the cavitation pressure in the computation of the cavitating flow field and cavitation coefficient leads to serious inaccuracies of real results.
常近时. 工质为浑水时水泵与水轮机的空化与空蚀[J]. 排灌机械工程学报, 2010, 28(2): 93-97.
Chang Jinshi. Cavitation and cavitation erosion of pump and turbine with silt laden water as working medium. Journal of Drainage and Irrigation Machinery Engin, 2010, 28(2): 93-97.
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