为了提高Schnerr⁃Sauer模型模拟空化流动的能力，基于 Rayleigh⁃Plesset方程和均相流假设建立了一种修正的Schnerr⁃Sauer空化模型，修正后的模型考虑了湍动能引起的脉动压力和不可凝结气体的影响。联立涡粘度系数修正的SST k⁃ω湍流模型，对绕二维Clark⁃Y翼型空化流进行了非定常数值计算，得到了时均化升阻力系数随空化数的变化曲线、云状空化时空泡周期性演变及其水平速度分布规律。通过与已有文献的实验结果对比分析得到，采用修正后的空化模型计算得到的时均化升阻力系数与实验值更为接近，并能较准确地捕捉升阻力系数随空化数的特殊变化规律；修正后的 Schnerr⁃Sauer模型能准确地模拟翼型表面空化云的初生、成长、脱落和溃灭的全过程。本文的研究结果验证了修正后的 Schnerr⁃Sauer模型在水翼空化流数值计算中的可靠性和准确性。%To enhance the capability of Schnerr⁃Sauer model in simulating cavitating flows, in this study, we devel⁃oped an improved Schnerr⁃Sauer model based on the Rayleigh⁃Plesset equation and homogeneous flow assumption. The model considers the effects of turbulent fluctuation and noncondensable gas. The unsteady cavitating flow over a two⁃dimensional Clark⁃Y hydrofoil was numerically investigated combined with the SST k⁃ω turbulence model, in which the turbulence eddy viscosity is corrected. We obtain the time⁃averaged lift and drag coefficients, the cavity shape evolution at cloud cavitation, and its x⁃velocity profiles from these calculations. Compared with available ex⁃perimental data in the literature, the time⁃averaged lift and drag coefficients predicted from the improved Schnerr⁃Sauer model agree better with the experimental results than with those of the original. In addition, the modified model can accurately predict the characteristics of the time⁃averaged lift and drag coefficients during different cavi⁃tation conditions. Moreover, the improved model can better simulate the inception, growth, shedding, and collapse of cloud cavitation than the original model. The overall results prove the reliability and accuracy of the improved Schnerr⁃Sauer model in cavitating flow simulations over a hydrofoil.
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