气膜孔位置对突肩叶尖气膜冷却效率的影响

采用标准k-ε两方程模型求解雷诺平均Navier-Stokes方程组，研究了气膜孔位置对突肩叶尖间隙泄漏流场、气膜冷却效率和表面传热系数的影响，共模拟了3种气膜孔排布方式:中弧线气膜孔、吸力侧气膜孔、前缘气膜孔，考虑了间隙高度（t）和吹风比（M）的影响。研究结果表明:在冷气流量相同的情况下气膜孔位置对突肩叶尖气膜冷却效率影响很大，中弧线气膜冷却突肩叶尖在中弧线到压力侧突肩区域有较好的气膜覆盖；吸力侧气膜冷却突肩叶尖在中弦处的吸力侧突肩到中弧线区域和尾缘区域有较好的气膜覆盖；前缘气膜孔突肩叶尖在整个叶尖表面都有较好的气膜覆盖。间隙高度对不同突肩叶尖的影响不同。吹风比增大时前缘气膜孔突肩叶尖的气膜冷却效率增幅远大于其余两种排布方式。 

Effect of film hole location on film-cooling effectiveness of squealer tip

The effects of film hole location on squealer tip leakage flow field,film-cooling effectiveness and surface heat transfer coefficient were studied by solving the Reynolds averaged Navier-Stokes equations using standard two equation k-ε model.Three film hole location configurations:camber line film holes,suction side film holes,leading edge film holes were simulated.The effects of tip clearance height (t) and blowing ratio (M) were also considered.The results showed that the film hole location affected the film-cooling effectiveness of squealer tip greatly under the same cooling flow rate.The camber line film cooling squealer tip had better film coverage on the region between the camber line and the pressure side squealer.The suction side film cooling squealer tip had better film coverage on the given middle chord region between the suction side squealer and the camber line,as well as on the trailing edge region.The leading edge film cooling squealer tip had better film coverage on all the tip surface.The tip clearance height had different effects on different squealer tips.The tip film-cooling effectiveness of the leading edge film cooling squealer tip increased greatly when the blowing ratio increased if compared with the other two kinds of cooling squealer tips.