弯曲段壁面冲击发散冷却效率的实验

Film cooling effectiveness experiment of impingementeffusion cooling in curved section

关键词:  回流燃烧室  结构设计  传热  冷却效率

Key words:  Reverse-flow combustion chamber  Structural design  Convective heat transfer  Cooling effectiveness

摘要:

为了研究回流燃烧室弯曲段采用冲击发散冷却结构形式对冷却效率的影响规律,设计了多种不同几何尺寸的计算模型,采用试验方式分别对其冷却效果进行了试验研究,得出了如下结论:(1) 吹风比对冷却效率影响显著,随着吹风比的增大冷却效率升高。沿整个弯曲段冷却效率呈现先增加后减小的趋势,但是变化幅度很小。(2) 弯曲段冲击发散冷却结构发散孔倾角对冷却效率影响很大,冷却效率随着发散孔倾角的减小而增大。(3)发散孔纵向间距小的发散孔板冷却效率高于纵向间距大的发散孔板的冷却效率。

Abstract:

In order to experimentally study the cooling effectiveness of impingement effusion cooling in curved section of combustion chamber, several test pieces with different geometrical dimensions were designed. The research results from the experiment show that:there is a obvious effect for the blowing ratio on the cooling effectiveness, and the cooling effectiveness is increased with the increase of blowing ratio. Initially, the cooling effectiveness is slowly increased on the effusion plate, and then is keeps a steady value, but at the rear end of the effusion plate, it is slowly decreased. There is a large effect for the effusion hole angle on the cooling effectiveness. It is increased with the decrease of the effusion hole angle and it is decreased when the jet holes spacing is increased.