双层壳型冲击/气膜结构内表面换热特性实验

Experiment on local heat transfer coefficient of a double-decker jet impingement/gimm cooling structure

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,进行了该种结构典型冷却单元的放大模型实验研究。通过改变冲击Re数（10 000～40 000）,冲击间距和冲击孔直径之比H/D（0.17～2.0）,冲击孔和气膜孔间距与冲击孔直径之比P/D（0～5.0）等参数,利用热膜法研究了该典型冷却单元结构中内表面的换热特性。研究结果表明：参数Re,H/D,P/D对内表面局部换热系数的影响呈现出复杂的关联性。在本文的实验工况参数条件下,随着冲击Re数的增加,内表面换热效果逐步增强;并且存在一个最佳的H/D和P/D范围使得内表面换热效果最佳。综合分析实验结果,当H/D=0.67,P/D=3时,双层壳型冲击/气膜冷却结构内表面能达到最佳的换热效果。

Experiments were carried out to investigate the heat transfer coefficient on inner surface of a lamellar double-decker jet impingement/film structure.Impingement Reynolds number（10 000～40 000）,the ratio of the jet impingement distance to the diameter of the jet hole H/D（0.17～2.0）,the ratio of the distance between the jet hole and film hole to the diameter of the jet hole P/D（0～5.0）were changed to study the rules of local heat transfer coefficient varying with these parameters.All the results show impingement Reynolds number,H/D and P/D affected heat transfer on inner surface together and the rules are complex.In experiments,higher heat transfer coefficient was achieved under larger impingement Reynolds number conditions.And there exists a proper range of H/D and P/D,which can result in a maximum heat transfer coefficient.It is verified that when H/D=0.67 and P/D=3,the maximum heat transfer coefficient can be achieved.