摘要
利用相似理论的原理，试验研究了封闭小空间内冲击／气膜复合冷却内表面的换热特性．研究中通过改变冲击RP数（10000-40000）、冲击距离H和冲击孔直径D之比H／D（0．17～2．0），在2种冲击孔和气膜孔间距P和冲击孔直径D之比P／D（0，1）条件下，细致分析冲击RP数、H／D对复合冷却内表面局部换热特性的影响．结果表明，在本文的试验工况中，冲击靶板上的局部Nu数随着冲击Re的增加而不断变大，而Nu数随着H／D的变化规律并非单调．当P／D=0，H／D=2时换热效果达到最佳；P／D=1时，在X／D=±3范围内，小冲击RP数条件下H／D=0．17和H／D=2的换热效果比较接近，大冲击RP数条件下H／D=1和H／D=2的换热效果比较接近．
Experiments were carried out to investigate the heat transfer of compound cooling （impinging cooling with outflow film）. Local heat transfer coefficients on inner surface were obtained over a Reynolds number range of 10 000-40 000, nozzle-to-plate spacing H/D range of 0. 17-2.0, the ratio between impinging jet and film hole distance to jet hole diameter P/D range of 0 and 1. Experimental results show that the local heat transfer coefficient was affected by impingement Reynolds number and nozzle-to-plate spacing greatly. Under the parameters in this paper, the local Nu number increased with the impingement Reynolds number. When P/D=0, the maximum Nu number was achieved while H/D=2. When P/D increased to unity, the maximum Nu number was gotten while H/D=2 and 0.17 under lower impingement Reynolds number. And this proper value of HID will change to be 2 and 1 under higher impingement Reynolds number.
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2007年第3期352-359,共8页
Journal of Aerospace Power
关键词
航空
航天推进系统
换热
冲击
复合冷却
aerospace propulsion system
heat transfer
impinging
compound cooling
