To improve the simulation accuracy of hydrofoil unsteady cavitation, a user-defined density function is used to correct a variety of turbulence models and combined with a hydrofoil with an angle of attack of 8° for numerical simulation of unsteady cavitation. This study aims to find the optimal turbulence model and apply it to other hydrofoil types to verify its applicability. The results show that the corrected RNG - turbulence model and SST - turbulence model can better fit the experimental results in terms of cavitation morphology and cavitation shedding frequency. The frequency error of cavitation detachment for the corrected SST - turbulence model is just 0.3% compared to the experimental results, and it shows an improvement of approximately 67% over the uncorrected SST - turbulence model. The corrected SST - turbulence model can more accurately capture the shedding cavitation due to the re-entrant jet, better capture the generation of the attached cavitation edge of the U-shape, the shedding of large-scale cavities, and the collapse of the shedding cavitation downstream. Furthermore, the optimal turbulence model has a good applicability in different dimensions and on different hydrofoil types.

中文翻译：

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水翼表面空化流及湍流模型适用性分析


为了提高水翼非定常空化的模拟精度，采用自定义密度函数对多种湍流模型进行修正，并结合攻角为8°的水翼进行非定常空化数值模拟。本研究旨在寻找最佳湍流模型并将其应用于其他水翼类型以验证其适用性。结果表明，修正后的RNG-湍流模型和SST-湍流模型在空化形态和空化脱落频率方面能够更好地拟合实验结果。与实验结果相比，校正后的SST-湍流模型的空化脱离频率误差仅为0.3%，比未校正的SST-湍流模型提高了约67%。修正后的SST-湍流模型可以更准确地捕捉再入射流造成的脱落空化，更好地捕捉U型附着空化边缘的生成、大尺度空洞的脱落以及脱落的崩溃下游空化。此外，最优湍流模型在不同尺寸和不同水翼类型上具有良好的适用性。