关键词: 航空发动机, 涡轮叶片, 气膜冷却, 双出口孔, 冷却效率, 数值模拟

Abstract: In order to understand the performance of film cooling with double-outlet holes, which is composed of a cylindrical hole and a conical hole, three-dimensional simulations of flow and temperature distributions with film cooling have been studied by commercial code. The mainstream Reynolds number is 10 000 and the blowing ratio varies from 0.5 to 2.0. The film cooling effectiveness contour, laterally averaged film cooling effectiveness, and the flow and temperature distributions near the surface have been obtained. The results show that the film cooling effectiveness with cylindrical hole injection agrees well with the experimental data. The double-outlet hole injections provide very high and laterally uniform film cooling effectiveness as compared to the case of cylindrical hole injections. The flow with double-outlet hole injection is significantly different from that with cylindrical hole injection. The increasing blowing ratio causes the increasing film cooling effectiveness, and the optimal blowing ratio is 1.5 .

Key words: aeroengine, turbine blade, film cooling, double-outlet hole, cooling effectiveness, numerical simulation