摘要
采用可进行全表面测量的瞬态液晶传热测量技术,实验研究了带肋横流进气方式下,不同横流雷诺数(Re_c=100000,50000)和吹风比(M=0.5,1,2)对圆柱形孔气膜冷却效率和换热系数比的影响,结果表明:受横流进气方式的影响,气膜冷却效率和换热系数的空间分布都呈现出一定的不对称性;相同吹风比下,横流雷诺数越高,冷却效率越高,而且在大吹风比下,这种影响更为显著;相同横流雷诺数下,换热系数比均随吹风比的增大而增大,气膜冷却效率则是随着吹风比增大先升高后降低;在大吹风比、低横流雷诺数工况下,气膜孔出口和孔间会形成强换热区。
Experimental measurements have been carried out to investigate the film cooling characteristics of cylindrical holes with coolant crossflow in ribbed channel.The local film cooling effectiveness and heat transfer coefficient were measured with transient liquid crystal technique over a series of crossflow Reynolds number and blowing ratio.The results show that the ribbed channel crossflow produces asymmetrical distributions for film cooling effectiveness and heat transfer coefficient.The crossflow can enhance the lateral spreading of film jets.Larger crossflow Reynolds number produces higher film cooling effectiveness,especially at high blowing ratios.Under the same crossflow Reynolds number,the heat transfer coefficient increases as the blowing ratio increases,while the film cooling effectiveness increases firstly and then decreases.Under conditions with small crossflow Reynolds number and high blowing ratio,heat transfer is notably enhanced in the midspan region of adjacent holes and the region near hole exit.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2015年第10期2211-2216,共6页
Journal of Engineering Thermophysics
基金
航空科学基金资助项目(No.2014ZB53023)
国家自然科学基金资助项目(No.51306152)
国家"973"计划资助项目(No.2013CB035702)
中央高校基本科研业务费专项资金资助项目(No.3102014JCQ01049)
关键词
带肋横流
气膜冷却
热色液晶
冷却效率
换热系数
ribbed crossflow
film cooling
liquid crystal
cooling effectiveness
heat transfer coefficient
