中文摘要：

为了获得气膜孔上游放置斜坡对气膜孔换热特性的影响规律，采用数值模拟方法研究了斜坡的台阶高度分别为0．3D，0．5D和0．75D（D为气膜孔直径）时在不同吹风比下的流动过程和换热特性分布情况，并与常规气膜孔冷却结构形式进行了对比。研究表明：在气膜孔上游设置斜坡，延缓了主流通过反向涡对对冷却气流的掺混作用，反向涡对强度减弱，冷却气流出流后的贴壁效果更好，提高了气膜孔出口下游的冷却效率和换热系数，并且随着斜坡高度的增高，效果更为显著。吹风比M=1．0时，斜坡对气膜孔出口下游换热系数的改善作用更强。

英文摘要：

To investigate the influence of an upstream ramp on film cooling heat transfer coefficient, a numerical simulation method on the distributions of the flow fields and heat transfer coefficient was adopted with different heights of upstream ramps in several ratios. And their distributions were compared with the distributions of baseline holes to reveal the good effects of the upstream ramps on the film heat transfer performance. The results show that the upstream ramp delays the entrainment of hot gases by the counter-rotating vortex pairs （CRVP） in the film-cooling jets and reduces the effect of CRVP, so the film effectiveness and heat transfer coefficient are higher with better coverage on the hot side especially with higher upstream ramp. And the improvement of the heat transfer coefficient is more significant at blowing ratio M=1.0.