为获得涡轮导向叶片气膜冷却特性，在叶栅风洞中运用红外热成像技术进行了带前缘对吹孔涡轮导向叶片的气膜冷却特性实验。叶片前缘布置5排复合角气膜孔形成对吹孔结构，其特点是叶片高度方向的上下两部分气膜孔径向角都偏向中截面。吸力面和压力面分别布置5排和16排圆形孔。测试的叶栅入口雷诺数为1.2×105，2.4×105和3.6×105，吹风比为1.0，1.5和2.0。实验结果表明：从前缘对吹孔出流的冷气向吸力面和压力面中截面聚集，导致中截面区域气膜覆盖效果增强；吹风比为1.0时，前缘和压力面中截面换热系数低；随吹风比增加中截面换热增强，压力面和吸力面高换热区域沿流向变长；雷诺数为1.2×105时，压力面气膜覆盖呈发散状；雷诺数为2.4×105和3.6×105时，压力面气膜覆盖宽度沿流向先变窄后变宽。

Using infrared thermal imaging technology, the film cooling performance of turbine guide vanes with leading edge counterinclined structure in a cascade wind tunnel was tested. There were 5 rows of compound angle film holes arranging on the leading edge of the vane to form a counterinclined structure,which was characterized that both the radial angles of upper and lower film apertures in the blade height direction were inclined to the middle section. The suction side and the pressure side were arranged with 5 rows and 16 rows of circular holes respectively.The Reynolds numbers of tested cascade inlets were 1.2×105, 2.4×105 and 3.6×105, the blowing ratios were 1.0, 1.5 and 2.0. The experimental results show that the cold air flowing from leading edge counterinclined structure gathers on the middle section of the suction surface and the pressure surface, resulting in an enhanced air film covering effect in the middle section area. When the blowing ratio is 1.0, the heat transfer coefficient at the middle section of the leading edge and the pressure surface is low. 〖JP2〗With the increase of blowing ratio, the heat transfer at the middle section is enhanced,the high heat exchange area of〖JP〗 pressure surface and suction surface becomes longer along the flow direction. When the Reynolds number is 1.2×105, the air film covering on the pressure surface is divergent; when the Reynolds numbers are 2.4×105 and 3.6×105, the air film coverage width of the pressure surface narrows first and then widens along the flow direction.

TK47

国家科技专项(2017-JCJQ-ZD-031)