高升力低压涡轮叶栅分离诱导转捩数值模拟研究

Numerical Simulation Study of the Separation-induced Transition for High-lift Low Pressure Turbine Cascade

准确地预测叶片吸力面层流分离诱导转捩过程是高升力、低压涡轮气动设计的关键。应用RANS方法的γ槇-Reθt转捩模型和LES方法的WALE亚格子模型对T106C高升力低压涡轮叶栅进行计算分析;比较了两种方法在不同雷诺数工况下对分离流转捩的模拟精度。结果显示,在高雷诺数工况时,γ槇-Reθt转捩模型预测结果与试验值较为一致,而在低雷诺数工况时严重低估了分离泡尺寸,与试验结果差距较大;WALE模型在高、低两种雷诺数工况下,其时均结果与试验值均吻合较好。

It is key point for high-lift low pressure turbine aerodynamic design that predicting exactly laminar separation induced transition at the blade suction. The γ-Re_（θt） transition model of RANS method and WALE sub-grid scale model of LES method were used to calculate the T106 C high-lift low pressure turbine cascade,and this two methods were compared for the simulated accuracy of separated flow transition under variant Reynolds number conditions. It is shown that the calculated results of γ-Re_（θt） transition model are well agreed with the experimental results with the high Reynolds condition. However the length of separation bubble is underestimated under low Reynolds condition,which induces the calculated results having great difference with the experiment. The timeaverage results of LES are well agreed with the experimental results with the high and low Reynolds conditions.