质量流量比对全气膜冷却叶片冷却特性影响的实验研究

采用瞬态液晶技术获得了全气膜冷却涡轮导向叶片全表面的高分辨率气膜冷却效率分布云图。实验在放大模型中完成，叶栅构成为三叶片两通道，叶栅进口雷诺数是1.0?05。叶片前缘有8排扩张型孔，压力面有21排轴向角孔，吸力面有24排轴向角孔。气膜孔排由２个供气腔供气，前腔二次流与主流的质量流量比为4.56%，后腔为4.67%。结果表明：受叶栅通道涡作用，气膜出流在吸力面呈聚敛状，在压力面则呈发散状。在三种质量流量比情况下，叶片平均冷却效率分布大体一致。随质量流量比的提升，叶片平均冷却效率提高，叶片前缘区域，气膜冷却效率提升更加明显。

experimental study of effects of mass flow ratio on film cooling effectiveness on full surface cooling vane

High-resolution heat transfer coefficient and film effectiveness measurements on a full-film cooling nozzle guide vane with compound and axial angle holes are obtained using a transient liquid crystal technique.Tests were performed in a scaled-up,two-passage cascade at an inlet Reynolds number of 1.0×105.There are 8 rows of compound angle cylinder film holes around the leading edge,21 rows of axial angle cylinder holes on the pressure side,and 24 rows of axial angle cylinder holes on the suction side.The holes are fed from one of two internal cavities with a mass flow ratio of 4.56% in the first plenum and 4.67% in the second plenum.Results show that the film cover region shrinks on the suction side and expands on the pressure side as the influence of passage vortex.As for the three mass flow ratios,the mean effectiveness of film cooling stay the same.The results show that MFR has a little influence film cooling effectiveness,and as MFR increases,the heat transfer coefficient and film cooling effectiveness increase at the same time.On the leading edge of the blade,film cooling effectiveness has a better improvement.