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本文采用数值模拟的方法,在保持冷却射流出口面积不变的条件F,分析比较了圆柱形孔、扇形孔、双射流孔和带双肩形孔这几种气膜孔的冷却效果.研究结果表明:对于圆柱形孔,气膜冷却效率在吹风比M=0.5左右效率较高;对于扇形孔,在对应圆柱形孔吹风比M=1.5时的效率要优于低吹风比情况;对于双射流孔和带双肩形孔,在对应圆柱形孔吹风比M=1.0时的冷却效果更好.原因在于高吹风比情况下,圆柱形孔结构中冷却射流与高温主流形成较强的肾形涡,会使冷却气体脱离壁面,并将高温主流卷入冷却气膜层,从而破坏冷却效果,而扇形孔、双射流孔以及带双肩形孔能有效地抑制肾形涡对冷却流的提升作用,从而保持冷却气膜的贴壁性,提高了气膜冷却效率.“,”The present study numerically investigates the film cooling effectiveness of four types of film cooling holes,a cylindrical hole,a fan-shaped hole,double jet holes and a hole with sister holes while keeping the flow area and flow rate constant.The results show that the film cooling effectiveness is highest at the blowing ratio of M=0.5 for the cylindrical hole,while for the fan-shaped hole,the film cooling effectiveness is highest at a blowing ratio of M 1.5.For the double jet holes and the hole with sister holes,the film cooling effectiveness is highest at a blowing ratio of M 1.0.The reason is that the interactions between the mainstream and the cooling stream produce counter-rotating vortex pairs (CVP) at high blowing ratios for the cylindrical hole which push the hot mainstream underneath the cooling stream and lift the cooling film from the surface.The other three hole shapes weaken the effect of the counter-rotating vortex pairs,resulting in more of the cooling stream adhering to the surface downstream which improves the cooling efficiency.