【摘要】 为深入了解两相共存超空化的非定常特性,分别采用标准RNGk-ε模型及其修正模型,计算了绕水翼的超空化流动,并通过与实验结果的对比对各个模型进行了评价。计算结果表明:标准RNGk-ε模型及其修正模型均可以模拟绕水翼的超空化流动状况,能比较准确地模拟两相共存超空化阶段汽相和水汽混合相界面的反向波动过程;模型常数的不同主要表现为对空穴内逆压梯度的影响,并由此导致了计算获得的最大空穴长度以及两相界面反向波动速度的差异;超空化区域内水汽两相的变化与压强分布均存在对应关系,压强的变化导致了水汽两相界面的反向波动。更多还原

【Abstract】 Supercavitating flows around a hydrofoil is simulated to deeply grasp the unsteady behaviour by a numerical method. To compare the effects of different turbulence model constants, the standard RNG k-ε model and modified ones with various model constants were implemented. The numerical results were compared with experimental ones to evaluate the applications of the models in the computations of supercavitating flows. The results show that all the models can simulate unsteady supercavitating behavior, and obtain the reverse fluctuating processes of the interface between the vapor phase and water-vapor mixture phase in current supercavitation stage. The different model constants affect the converse grads of the pressure mostly, which result in the difference of maxium cavity length and the interface’s fluctuating velocity. The variation of the volume fraction between water and vapor phases is related to pressure distribution in cavity area, in which the pressure waving leads to the reverse fluctuating of the two-phase interface.更多还原