Experimental investigation on impingement-effusion film-cooling behaviors in curve section

A new series of test pieces with different geometrical configuration and geometry dimensions are designed to experimentally investigate on impingement-effusion cooling behavior in curve effusion wall of combustion chamber. The test results show that the discharge coefficient increased with the increasing blowing ratio. The effusion hole–hole spacing has an effect on the discharge coefficient and the discharge coefficient commonly decreased with the increment of effusion hole–hole spacing. The blowing ratio greatly effects cooling behavior. The bigger blowing ratio is favorable for improving cooling characters. At the curved effusion wall, to begin with, cooling effectiveness increased slowly and kept a steady value in subsequence. But, for the rear end of curved effusion wall, it decreased slowly. With decreasing of effusion hole angle and effusion hole–hole spacing, cooling effectiveness is enhanced. Meanwhile, blowing ratio, effusion angle and effusion hole–hole spacing take an evident effect on the discharge coefficient.