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本文通过热敏液晶瞬态测量技术对狭窄空间内的光滑靶板和带有针肋扰流的表面冲击冷却展开了实验研究,射流Reynolds数范围15000～30000.实验获得了冲击靶板表面高精度的局部Nusselt数分布,通过分析获得了如下结论:1)两种靶板上的横向平均Nusselt数比Nuu/(Re0.8 Pr1 /3)变化趋势均几乎不随Re数变化;2)带有针肋的表面冲击冷却其端壁平均传热性能比光滑靶板高约7.0％,压力损失最大提高约17.9％;3)带有针肋的表面冲击靶板上传热驻点的分布与光滑靶板几乎一致,针肋的存在不影响横流导致的射流偏移作用;4)由于针肋显著地增加了冲击冷却系统中的换热面积,因此针肋表面的射流冲击总体传热性能会比光滑表面射流冲击显著提高.“,”Experiments using transient liquid crystal technique were carried out on confined jets impingement onto flat target plate and target plate with round pin fins of the Reynolds number 15000～30000.High precision local Nusselt numbers were obtained and some conclusions were drawn:1) The spanwise averaged Nusselt number ratios Nu/(Re~8PrU3) almost didn't vary with Reynolds numbers.2) The Nusselt number of the target plate with pin fins could be increased by about 7.0％ than that of fiat plate,and the pressure loss increased by 17.9％.3) The heat transfer stagnation points of the target plate with pin fins had similar distribution as fiat plate.That is,the pin fins had little effect on the skewness of jets caused by crossflow.4) The pin fins significantly increased the heat transfer area of the target plate with pin fins than flat plate,and would enhanced the overall heat transfer performance a lot.