The mechanism of flow instability, which involves complex gas–liquid interactions and multiscale vortical structures, is one of the hot research areas in cavitating flow. The role of turbulence modeling is crucial in the numerical investigation of unsteady flow characteristics. Although large-eddy simulation (LES) has been used as a reliable numerical method, it is computationally costly. In this work, we used a hybrid Reynolds-averaged Navier–Stokes (RANS) and LES model, that is, stress-blended eddy simulation (SBES), to improve the prediction capability for the cloud cavitating flow. Our hybrid approach introduces a shielding function to integrate the RANS model with the LES applied only regionally, such as to large-scale separated flow regions. The results showed that the periodic shedding of cavity growth, break off, and collapse around a three-dimensional Clark-Y hydrofoil was reproduced in accordance with experimental observations. The lift/drag coefficients, streamwise velocity profiles, and cavity patterns obtained by the SBES model were in better agreement with the experimental data than those obtained by the modified RANS model. The re-entrant jet dynamics responsible for the break off of the attached cavity were discussed. Further analysis of vorticity transportation indicated that the stretching and dilatation terms dominated the development of vorticity around the hydrofoil. In conclusion, the SBES model can be used to predict cavitating turbulent flows in practical engineering applications.

涉及复杂的气液相互作用和多尺度涡旋结构的流动不稳定机理是空化流动的热点研究领域之一。湍流建模的作用在非定常流动特性的数值研究中至关重要。尽管大涡模拟 (LES) 已被用作可靠的数值方法，但其计算成本很高。在这项工作中，我们使用混合雷诺平均 Navier-Stokes (RANS) 和 LES 模型，即应力混合涡流模拟 (SBES)，来提高云空化流的预测能力。我们的混合方法引入了屏蔽功能，将 RANS 模型与仅应用于区域的 LES 集成，例如应用于大规模分离的流动区域。结果表明，空腔生长的周期性脱落、折断、并根据实验观察再现了三维克拉克-Y 水翼周围的坍塌。SBES 模型获得的升/阻力系数、流向速度剖面和空腔模式与实验数据相比，与改进的 RANS 模型获得的数据更加吻合。讨论了导致附着腔断裂的重入射流动力学。对涡量传递的进一步分析表明，拉伸和膨胀项主导了水翼周围涡量的发展。总之，SBES 模型可用于预测实际工程应用中的空化湍流。SBES 模型获得的空腔模式与实验数据的一致性比修改后的 RANS 模型获得的数据更吻合。讨论了导致附着腔断裂的重入射流动力学。对涡量传递的进一步分析表明，拉伸和膨胀项主导了水翼周围涡量的发展。总之，SBES 模型可用于预测实际工程应用中的空化湍流。SBES 模型获得的空腔模式与实验数据的一致性比修改后的 RANS 模型获得的数据更吻合。讨论了导致附着腔断裂的重入射流动力学。对涡量传递的进一步分析表明，拉伸和膨胀项主导了水翼周围涡量的发展。总之，SBES 模型可用于预测实际工程应用中的空化湍流。对涡量传递的进一步分析表明，拉伸和膨胀项主导了水翼周围涡量的发展。总之，SBES 模型可用于预测实际工程应用中的空化湍流。对涡量传递的进一步分析表明，拉伸和膨胀项主导了水翼周围涡量的发展。总之，SBES 模型可用于预测实际工程应用中的空化湍流。