带气膜孔出流和侧向出流的冲击换热实验

采用热色液晶瞬态测量技术测量了阵列孔冲击靶面的局部传热系数,获得了冲击雷诺数为5000,10000,15000,20000时侧向出流比(侧向出流质量流量与主流质量流量之比)为0,0.25,0.4,0.6,0.8,1时的靶面传热系数分布规律.结果表明:靶面的传热系数均随雷诺数的升高而升高;靶面上冲击驻点区域传热系数最大,气膜孔区域传热系数较高.靶面的平均传热系数随侧向出流比的增加而减小,侧向出流比较小时,靶面的平均传热系数下降幅度不大,较大时靶面的平均传热系数下降相对较明显.

Experiment of impingement heat transfer with film holes bleeding and side bleeding

A transient liquid crystal technique was used to measure the local heat transfer coefficients on a target surface with array impingement hole. The effects of jet Reynolds numbers (5000,10000,15000,20000) and the ratios of the side bleeding(0,0.25,0.4,0.6,0.8,1) on the heat transfer coefficients were investigated. Results show that,the heat transfer coefficients on the target surface rise with the increase of jet Reynolds number; the heat transfer coefficients on the impingement stagnation regions are the highest,and the heat transfer coefficients on the film holes regions are also relatively high. The average heat transfer coefficients on the target surface decrease with the increase of the ratio of the side bleeding,and are not strongly influenced with the low ratio of side bleeding,but significantly affected with the high ratio of side bleeding.