论文部分内容阅读
为了了解涡轮导叶吸力面在跨声速条件下的换热特性,采用数值模拟的方法,分析了出口马赫数对平面叶栅内流场与换热特性的影响,以及气膜出流对吸力面气膜冷却特性的影响。结果表明,跨声速条件下,斜激波导致的逆压梯度导致了吸力面层流边界层分离和转捩;亚声速条件下,吹风比从0.5增大至1.5时,转捩位置前移了约0.1倍弦长;跨声速条件的转捩位置随吹风比增大未发生变化,但是边界层分离现象被抑制,分离泡的尺寸明显变小。在吸力面小吹风比更容易获得更高的冷却效率;边界层的分离导致冷效率分布不同于亚声速条件,在分离区冷却效率迅速降低,在吹风比0.75时降低约50%。
In order to understand the heat transfer characteristics of turbine vane suction surface under transonic speed conditions, the effect of outlet Mach number on the flow field and heat transfer characteristics in plane cascade was analyzed by numerical simulation. The effects of gas outflow on suction surface Effect of film cooling characteristics. The results show that under the condition of transonic velocity, the reverse pressure gradients caused by oblique shocks lead to the separation and transition of the laminar boundary layer on the suction side. When the blowing ratio increases from 0.5 to 1.5, About 0.1 times the chord length. The transonic position did not change with the blowing ratio increasing, but the separation of the boundary layer was suppressed and the size of the separation bubble was obviously smaller. The separation efficiency of the boundary layer is different from that of the subsonic condition. The cooling efficiency in the separation zone decreases rapidly and decreases by about 50% at the blowing ratio of 0.75.