基于流固耦合的涡轮叶顶喷气冷却特性研究  

Tip cooling injection characteristic of turbine blade based on fluid⁃solid coupling method

作　　者：张筠松 刘永葆[1,2] 李钰洁[1,2] 贺星[1,2] ZHANG Yunsong;LIU Yongbao;LI Yujie;HE Xing(College of Power Engineering,Naval University of Engineering,Wuhan 430033,China;Military Key Laboratory for Naval Ship Power Engineering,Naval University of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学动力工程学院,武汉430033 [2]海军工程大学舰船动力工程军队重点实验室,武汉430033

出　　处：《哈尔滨工业大学学报》2020年第7期186-192,200,共8页Journal of Harbin Institute of Technology

基　　金：国防预研基金(4010303010303)。

摘　　要：高温燃气在涡轮动叶叶顶产生的泄漏流不但降低了涡轮效率,更是加剧了叶顶的热负荷.本文基于实验模型,采用流固耦合的数值计算方法,研究了涡轮凹槽叶顶的间隙流与冷却射流相互作用的流动机理以及顶部喷气冷却对凹槽壁面换热效果的影响,重点分析了吹风比、冷却孔倾斜角、冷却孔进气角以及固体材料导热系数对壁面Nu数的影响.结果表明:大吹风比(M=1.5)能有效改善凹槽近压力面一侧肋条及底部的换热,Nu数分布更加均匀;进气角产生的"喷射效应"改变了冷却气流高速区的出口相对位置,当进气角大于0°时,冷却气体能有效阻隔高温流体使壁面Nu数降低;低导热系数材料降低了气流对固体壁面的对流换热,使得壁面的对流换热更加均匀.The high-temperature gas leakage flow generated by the turbine tip clearance not only reduces the turbine efficiency,but also exacerbates the thermal load on the tip.Based on experimental model and numerical calculation method of fluid-solid coupling,the flow mechanism of the interaction between gap flow and cooling jet at the tip of turbine groove and the effect of top jet cooling on the heat transfer effect of the groove wall are studied.The effects of the ratio of cooling hole inclination angle,the cooling hole inlet angle,and the thermal conductivity of the solid material on the Nu number of the wall surface are analyzed.The results show that the large blow ratio(M=1.5)can effectively improve the heat transfer between the rib and the bottom of groove near the pressure side,and the Nu number distribution is more uniform.The"jet effect"generated by the intake angle changes the high-speed zone of the cooling airflow.Relative position of the outlet,when the intake angleβ>0°,the cooling gas can effectively block the high temperature fluid to reduce the Nu number of the wall surface.The low thermal conductivity material reduces the convective heat transfer of the airflow to the solid wall,so that the convective heat transfer of the wall surface is more uniform.

关 键 词：涡轮 流固耦合 冷却 传热 泄漏流 

分 类 号：V231.3[航空宇航科学与技术—航空宇航推进理论与工程]