不同叶片尾缘结构冷却效率的试验研究

为了研究不同叶片尾缘结构对冷却效果的影响规律,设计了3种尾缘结构,并搭建了试验台,采用红外热像仪对叶片尾缘的绝热壁温进行测量。研究结果表明:(1)3种尾缘结构的冷却效率沿壁面的分布有很大差异,针对试验件Ⅰ,冷却效率存在最大值,且最大值出现的位置随着吹风比的增加而逐渐远离气膜出口;(2)试验件Ⅱ和Ⅲ的冷却效率沿壁面均呈现逐渐降低的趋势,但降低的规律二者又不相同;(3)在相同壁面位置,试验件Ⅲ的冷却效率最高,试验件Ⅰ的冷却效率最低,因此可以认为,试验件Ⅲ所示的尾缘结构更有利于对叶片尾缘的冷却。

Experimental Study on Film Cooling Effectiveness of Turbine Blade Trailing Edges

In order to study the film cooling effectiveness of blade trailing edge,three kinds of trailing edges are designed,and the experimental system is built.The adiabatic cooling effectiveness of trail edges is studied by infrared cameras.The experimental result shows that the cooling effectiveness of the three kinds of trailing edges are different.There is a max film cooling effectiveness value of the test piece Ⅰ,and the point where the maxmum comes is moving away from the exit when the blowing ratio increases.The film cooling effectiveness of test pieces Ⅱ and Ⅲ both gradually decrease along the surface of trailing edge.At the same point of the surface of trailing edge,the cooling effectiveness of test piece Ⅲ is better than those of other two test pieces.Therefore the configuration of test piece Ⅲ is suitable for the design of turbine blade trailing edge.