Abstract：In order to investigate influences of re-entrant jet strength on periodical evolution of cavity attaching to the upper surface of a hydrofoil, several 2D meshes around a hydrofoil at different inflow angles are established. The distributions of pressure, velocity and phase features of cavitating flow field are analyzed by using CFD method. Unsteady cavitating flows over the 2D hydrofoil with different inflow angles are simulated with the RNG k-ε turbulence model and Schnerr-Sauer cavitation model. The re-entrant jet motion features and interaction with cavity are analyzed at 4°, 10° and 12° inflow angles and 0.91 cavitation number. Based on velocity, characteristic length and other parameters, a critical cavitation number is put forward to estimate the strength of re-entrant jet and serves a basis of judgment on change in cavity shape. The results show that the strength of re-entrant jet is an important factor influencing the structure of cavity. It is identified that the magnitude of criterial number can be correlated to different periodical stages and types of cavity.
王巍, 徐瑞铎, 羿琦, 王晓放. 回射流强度对水翼表面空化形态的影响[J]. 排灌机械工程学报, 2016, 34(11): 921-926.
WANG Wei, XU Ruiduo, YI Qi, WANG Xiaofang. Influence of re-entrant jet strength on cavitation characteristics of hydrofoil. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(11): 921-926.
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