气膜冷却对高压涡轮叶栅损失特性的影响研究

为获得全气膜气冷涡轮叶栅的损失特性，采用试验及数值仿真方法，研究了不同冷气流量、不同叶栅出口马赫数条件下冷气射流对叶栅损失的影响。通过叶栅槽道静压云图及叶片表面压力分布等试验及数值仿真结果对比，验证了通冷气叶栅性能仿真分析方法的准确性。结果表明：同一冷气流量比下，通冷气叶栅能量损失系数随着马赫数的增大先减小后增大，在设计马赫数附近损失最低；通冷气叶栅能量损失系数随着冷气流量的增大而增大，且前后腔均通冷气时能量损失系数最大，前腔单独通冷气时能量损失系数最小；通冷气叶栅能量损失系数随着冷气与主流温比增大而增大。

Research on the effect of film cooling on the loss characteristics of a high pressure turbine cascades

In order to obtain the loss characteristics of the fully film air cooled turbine cascade, experiments and numerical simulation methods were used to study the influence of cold air jet on cascade loss characteristics under different cold air flow rates and outlet Mach numbers conditions. The accuracy of the simulation analysis method for large cold air cascades was verified through comparison of experimental and numerical simulation results such as static pressure cloud map of the cascade channel and pressure distribution on the balde surface. The results show that under the same cold air flow rate ratio, the energy loss coefficient of air cooled cascades first decreases and then increases with the increase of Mach number, with the lowest loss near the design Mach number; the energy loss coefficient of the air cooled cascade increases with the increase of the cooling air flow rate ratio, and the energy loss coefficient is the highest when both the front and rear chambers are cooled, while the energy loss coefficient is the lowest when the front chamber is individually cooled; the energy loss coefficient of the air cooled cascade increases with the increase of the temperature ratio between the cooling air and the mainstream.