双层壳型冲击/气膜复合冷却效果的实验

以双层壳型冲击/气膜复合冷却结构的平壁模型作为研究对象,进行了该种冷却结构的复合冷却效果实验研究.研究中改变冷热气流吹风比M,冲击距H/d,冲击孔和气膜孔间距与冲击孔直径之比P/d等参数,利用红外热像仪拍摄实验件的温度分布.研究结果表明:上述参数均影响双层壳型冲击/气膜复合冷却效果,而且影响规律表现出较强的关联性.随着吹风比的增加,复合冷却效果逐步增强;在实验工况条件下,存在一个最佳冲击距H/d范围使得复合冷却效果最佳;同时在冲击孔和气膜孔之间也存在一个最佳的P/d范围,使得复合冷却效果达到最大.当H/d=0.5和P/d=4时,双层壳型冲击/气膜复合冷却结构能达到最佳的冷却效果.

Experimental investigation of a double-decker jet impingement/film structure's cooling coefficient

Experiments were conducted out to investigate cooling coefficient of a lamellar double-decker jet impingement/film structure.Blowing rate M,the ratio of the jet impingement distance to the diameter of the jet hole H/d,and the ratio of the distance between the jet hole and film hole to the diameter of the jet hole P/d were changed to study the rules of local cooling coefficient varying with these parameters.All the results show that higher cooling coefficient was achieved under larger blowing rate conditions.And there exists a proper range of H/d and P/d,which can result in a maximum cooling coefficient.It is verified that when H/d=0.5 and P/d=4,the maximum cooling coefficient can be achieved.