In this paper, the large eddy simulation (LES) method in conjunction with the Zwart cavitation model is adopted for the assessment of the erosion risk on a hydrofoil surface. The numerical results are in good agreement with the experiments. On this basis, three methods, namely the intensity function method (IFM), the time-averaged aggressiveness indicators (TAIs) and the gray level method (GLM), are applied for the assessment of the erosion risk. It is shown that the erosion intensity index of the IFM is extremely sensitive to the artificially selected thresholds, which greatly limits the application of the method. The erosion risk predicted by four indicators in the TAIs does not agree well with the experimental results. Further analysis demonstrates that the GLM using the instantaneous pressure field is relatively satisfactory, which can provide a reasonable assessment of the erosion and is not very sensitive to the artificially selected thresholds. To further improve the accuracy of the GLM for the erosion risk prediction, the time-average pressure field is adopted in the GLM for the erosion evaluation. It is suggested that the erosion assessment by using the time-averaged pressure field is in better agreement with the experimental results when compared with that by using the instantaneous pressure field.

本文采用大涡模拟(LES)方法结合Zwart空化模型对水翼表面的侵蚀风险进行评估。数值结果与实验吻合良好。在此基础上，采用强度函数法（IFM）、时间平均侵蚀性指标（TAI）和灰度法（GLM）三种方法对侵蚀风险进行评估。结果表明，IFM的侵蚀强度指数对人为选择的阈值极为敏感，极大地限制了该方法的应用。TAI 中四个指标预测的侵蚀风险与实验结果不一致。进一步分析表明，使用瞬时压力场的 GLM 比较令人满意，它可以提供对侵蚀的合理评估，并且对人工选择的阈值不是很敏感。为了进一步提高 GLM 对侵蚀风险预测的准确性，GLM 中采用时均压力场进行侵蚀评估。这表明，与使用瞬时压力场相比，使用时均压力场进行侵蚀评估更符合实验结果。