不同来流附面层厚度下容腔泄漏流对围带式静叶性能影响

基于验证的数值模拟方法，针对带容腔结构的围带式静叶，研究了容腔泄漏流对其性能的影响以及容腔泄漏流与主流的相互干涉作用。在不同的来流附面层厚度下，探讨了叶栅二次流运动和角区分离发展情况，并通过总压损失系数和熵增系数对性能变化进行评判。结果表明：附面层厚度的增加使无容腔扩压叶栅总压损失系数和熵增损失系数增加。容腔泄漏流使叶片前缘出现容腔泄漏涡，并对通道涡的发展和集中脱落涡的大小产生影响；同时容腔泄漏流加强了叶栅通道内的三维流动效应，削弱了近端壁面流体的横向偏转；随着附面层增厚，带容腔的扩压叶栅的总压损失系数和熵增损失系数变化程度不明显。

Influences of the cavity leakage flow on shrouded stator performance at different inlet boundary layer thicknesses

The impacts of the cavity leakage flow on the shrouded stator aerodynamic performance were investigated by modelling of the annular cascade mainstream with the seal cavity flow path based on the validated numerical method. Meanwhile, the interactions between the cavity leakage and the mainstream were also determined in the current study. The developments of hub corner separation under the action of leakage were discussed, while the total pressure loss coefficient and the entropy-based loss coefficient were employed to evaluate the performance changes at different boundary layer thicknesses. The results showed that the thickening of the boundary layer increased the total pressure loss coefficient and the entropy-based loss coefficient of diffuser cascade without cavity. The cavity leakage flow induced a new vortex near the blade leading edge, and had effect on the development of passage vortex and the size of concentrated shedding vortex. At the same time, the leakage flow strengthened the three-dimensional flow effect in the cascade passage and weakened the cross-passage deflection of the fluid near end-wall. As the boundary layer thickened, the variations of total pressure loss coefficient and entropy increase loss coefficient of diffuser cascade with cavity were not obvious.