Modern high-temperature gas turbine blades are often used inside and outside of the composite cooling structure,but the two parts of the structure of the flow heat transfer characteristics are separately studied,as a result of the internal and external flow heat transfer mechanism is very different,so the overall study the influences of the internal cooling structure on the external film cooling characteristics is very important.Effect of internal cooling structures for the external film cooling characteristics,it uses numerical simulation methods to investigate the influences of the different internal cooling structures on external film cooling performance,and reveals the mechanism on influence of different internal structures.The results show that the non-pin fins of film cooling effectives is better than the pin fins of film cooling effectives when the blowing ratio is lower.The external film cooling characteristics of the two structures are the best when the blowing ration is 0.5.The non-pin fins of film cooling are similar to the pin fins of film cooling.In-line of the film cooling effectiveness is better than the staggered,but the staggered downstream of the width of the film covering is better than in-line.Therefore,it is recommended to use the staggered of film cooling when the multi-row film cooling.It can be concluded that the film cooling performance is the best one among the several structures under the long-distance between the pin fins and the film holes of the in-line structure at the blowing ratio of 0.5.%现代高温燃气涡轮叶片常采用内外复合冷却结构,但两部分结构的流动换热特性多是分开单独进行研究的,由于内部和外部流动换热机理有很大差别,因此整体研究内部冷却结构对外部气膜冷却特性的影响就十分重要.通过数值模拟方法研究不同内冷结构对外部气膜冷却特性的影响,揭示不同内部结构的对外部气膜冷却特性的影响机理.研究结果表明,在小吹风比下,有扰流柱的气膜冷却效率优于无扰流柱.吹风比均在0.5时,两种结构外部气膜冷却特性均为最佳.当吹风比大于1.0时,有无扰流柱的气膜冷却特性结果相近.顺排时,气膜冷却效果好于叉排方式,但叉排下游远处的气膜覆盖宽度要优于顺排,因此,针对多排气膜冷却时,推荐采用顺排结构的气膜冷却方式.总结可得,吹风比为0.5时,在扰流柱与气膜孔之间远距离顺排结构下,气膜冷却特性是这几个结构中相对最好的一种.
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