Abstract: In order to further clarify the effects of tangential coolant ejection on suction side on aerodynamic performance and film cooling effectiveness in a transonic turbine，numerical simulations were conducted on a transonic turbine cascade. Coolant slots were located at different positions on the suction side of blade and coolant was ejected at different blowing ratios to study the effects of tangential coolant slot on overall performance and detail of flow field of a transonic turbine cascade. The results showed that the tangential coolant ejection on suction side is good for minimizing the shock wave loss. The max Mach number can be reduced by more than 0.104. The energy loss coefficient has its minimum value when the coolant slot is placed upstream of the reflecting point of inner-extending shock wave and blowing ratio is between 0.75 to 1.00. The increasement of blowing ratio is beneficial to decrease the size of separation bubble inside the cooling slot，or even eliminate it. At the same time，the increasing blowing ratio is also good for decreasing the intensity of shock wave at the lip of cooling slot.

Key words: Transonic turbine；Film cooling；Tangential coolant ejection；Energy loss

摘要： 为进一步探究跨声速涡轮中吸力面切向冷气喷射对叶栅气动性能及气膜冷却效果的影响，以跨声速涡轮叶栅作为研究对象，采用数值模拟方法，通过在叶片吸力面不同位置开设切向冷气喷射槽，进行不同吹风比下的冷气喷射，对跨声速气冷涡轮叶栅的总体性能以及流场细节进行了详细研究。研究结果表明，吸力面切向冷气喷射有利于减小跨声速涡轮叶栅激波损失，叶栅最大马赫数可减小0.104；切向冷气喷射槽位于尾缘内伸激波反射点上游，且吹风比处于0.75～1.00内时，叶栅能量损失最小；吹风比的增大有利于减小甚至消除冷气槽内分离泡，并能够减小唇部激波强度。

关键词: 跨声速涡轮；气膜冷却；切向冷气喷射；能量损失