涡轮导叶压力面簸箕形气膜孔冷却特性实验研究

Experimental Study of Film Cooling Characteristics for Dust-Pan Shaped Holes on Pressure Side in a Turbine Guide Vane

关键词:  簸箕形孔，气膜冷却，压力面，雷诺数，吹风比

Key words:  Dust-pan shaped hole  Film cooling  Pressure side  Reynolds number  Blowing ratio

摘要:

为了获得涡轮导叶压力面不同位置处单排簸箕形气膜孔的气膜冷却特性，在短周期跨声速换热风洞中分别测量了涡轮导叶压力面4排簸箕形气膜孔的冷却效率，分别位于10.7%，21.1%，36.1%，64.3%相对弧长位置处，获得了不同主流雷诺数、马赫数、吹风比和孔位下簸箕形气膜孔冷却效率的分布。结果表明:在靠近前缘的孔1和孔2处，气膜冷却效率随着雷诺数的增大而减小，而在靠近尾缘的孔3和孔4处，小雷诺数(Re=2.0×105)下冷却效率最小，中高雷诺数(Re=4.0×105，6.0×105)的变化对冷却效率影响较小；各个孔位孔后弧长与孔径比x/d=0～40区域的平均冷却效率随着吹风比的增大而先升高后降低，在吹风比为1.0时平均冷却效率达到最高；靠近尾缘的孔位处气膜冷却效率更高，但随着距离的增大下降得也更快。

Abstract:

In order to study film cooling characteristics for single dust-pan shaped hole rows at different locations on turbine blade pressure side，film cooling effectiveness for four rows of dust-pan shaped holes on pressure side in a turbine guide vane was measured at short-duration transonic heat transfer wind tunnel，which are at 10.7%，21.1%，36.1%，64.3% relative arc respectively，and the distribution of film cooling effectiveness at different mainstream Reynolds number，Mach number，blowing ratio and position of the holes was obtained. The results indicate that the film cooling effectiveness decreases with the Reynolds number increasing for hole 1 and hole 2 near the leading，while the effectiveness is the lowest at low Reynolds number (Re=2.0×105) case for hole 3 and hole 4 near the trailing，where the change of Reynolds number has small effect on the effectiveness at middle and high Reynolds number(Re=4.0×105，6.0×105)case. Spatially averaged adiabatic effectiveness over the range displacement-to-diameter x/d=0 to 40 for all holes increases and then decreases with the blowing ratio increasing，and the highest averaged value is obtained at the blowing ratio of 1.0. Film cooling effectiveness for the holes near the trailing is higher compared with the case of the holes near the leading，but it decreases faster with the distance increasing.