尾迹对涡轮动叶全表面气膜冷却效率的影响

采用压敏漆（PSP）测量技术研究了尾迹对涡轮动叶气膜冷却效率的影响，测试叶片带有11排圆柱形气膜孔。获得了不同质量流量比和尾迹斯特劳哈尔数（Sr=0，0.12，0.36）条件下全表面气膜冷却效率分布的试验数据，结果表明：随着尾迹Sr数的增加，叶片前缘区域径向平均气膜冷却效率最大降低幅度达36.5%，吸力面径向平均气膜冷却效率最大降低幅度达53.5%，压力面径向平均气膜冷却效率最大降低幅度达24.2%；尾迹对前缘和吸力面气膜冷却效率的影响大于压力面；随着质量流量比增加，尾迹的影响减小；在进行涡轮动叶表面气膜冷却结构设计时，不考虑尾迹效应会增加设计风险。

Effect of unsteady wake on full coverage film cooling effectiveness for a turbine blade

The effect of unsteady wake on the film cooling effectiveness of the turbine blade is studied using the Pressure Sensitive Paint (PSP) measurement technique. The test blade has eleven rows of cylindrical film holes. The distribution of the film cooling effectiveness on the whole blade surface under different mass flux ratios and different wake Strouhal numbers (Sr=0, 0.12, 0.36) are obtained. The results show that as the wake Strouhal number increases, the radial averaged film cooling effectiveness of the leading edge decreases by up to 36.5%, the radial averaged film cooling effectiveness of the suction surface decreases by up to 53.5%, and that of the pressure surface decreases by up to 24.2%. The effect of wake on the leading edge and the suction surface is greater than that on the pressure surface. As the mass flux ratio increases, the effect of the unsteady wake decreases. When designing the cooling structure of the turbine blade, ignoring the effect of the wake increases the design risk.