Abstract: Experiments are conducted to investigate the flow and heat transfer characteristics of inner cooling channel with real engine sizes. The diameter of impingement holes and film holes are 0.3mm，0.4mm and 0.5mm，respectively. Ratios of the distance between the impingement plate and the target plate to the impingement hole diameter(H/D)are 2，2.5 and 3.0，respectively. Hole pitch to diameter ratios(P/D)are 5 and 10， respectively. The Reynolds number varies from 1000 to 10000，Knudsen number is equal to the Knudsen number in real working condition of engine. The thermodynamic characteristics of micro-scale impingement channels with different geometry are studied. The results show that with the same Reynolds number，average heat transfer coefficient of channel increases as the hole diameter decreases，and it decreases as the magnitude of H/D or P/D increases，and the empirical correlation has been fitted.

Key words: Impingement cooling；Micro-scale；Heat transfer coefficients；Reynolds

摘要： 为了研究真实发动机尺寸下冲击通道的流动与换热情况，选取冲击孔与气膜孔孔径均为D=0.3mm，0.4mm，0.5mm，冲击距H/D=2，2.5，3.0，孔间距P/D=5，10，雷诺数Re范围为1000～10000，保证与真实发动机工况相等的克努森数下，对不同结构微小冲击通道的整体换热情况进行分析比较。结果表明:在相同的雷诺数下，通道整体平均换热系数随着孔径的减小而增加，随着冲击距H/D的增加而减小，随着冲击孔间距P/D的增加而减小，并且拟合出了相关经验关系式。

关键词: 冲击冷却；微尺度；换热系数；雷诺数