热辐射对气膜冷却叶片表面热负荷的影响  

Effect of Thermal Radiation on the Thermal Load of a Film-Cooled Vane

作　　者：饶乐威 王天壹 连文磊[1] RAO Le-wei;WANG Tian-yi;LIAN Wen-lei(School of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 21006,China)

机构地区：[1]南京航空航天大学能源与动力学院,南京210016

出　　处：《航空发动机》2023年第4期38-47,共10页Aeroengine

基　　金：航空动力基础研究项目资助。

摘　　要：为了明确不同因素对叶片表面热负荷的影响规律,利用改进的WSGG模型,通过CFD数值仿真进行对流辐射耦合计算,探明高温燃气辐射传热对叶片表面热负荷的影响。结果表明:进口压力、温度、黑体辐射温度和壁面发射率对叶片表面热负荷均有一定影响,在进口总温从1750 K升高到2150 K的过程中,叶片表面温度整体升高幅度为250~300 K,而黑体辐射温度对叶片表面温度的提升最高为40 K。在壁面发射率从0.3提高到0.8的过程中,叶片表面辐射热流密度随之增大,在吸力面和压力面局部区域辐射热流密度增大了1倍。壁面发射率和高温燃气进口温度对叶片表面的温度和热流作用相当均匀,进口压力和黑体辐射温度对叶片尾缘、前缘和压力面的热负荷影响远大于其他区域。在此基础上,提出了以进口总温、黑体辐射温度、余气系数和壁面发射率为自变量,以辐射换热热流密度为因变量的辐射换热的经验准则关系式,获得了该经验关系式的拟合结果,并对该拟合精度进行了计算,相对误差均小于5%。Thermal radiation has a great influence on vane surface thermal load.To clarify the influence law of different factors on vane surface thermal load,an improved WSGG model was used to conduct convective radiation coupling calculation through CFD numerical simulation,and the influence of high-temperature gas radiation heat transfer on blade surface heat load was investigated.The results show that inlet pressure,temperature,blackbody radiation temperature,and wall emissivity all have a certain influence on vane surface thermal load.When the total inlet temperature rises from 1750 K to 2150 K,the vane temperature rises by 250 K-300 K,while the blackbody radiation temperature increases the vane temperature by 40 K at the highest.When the wall emissivity increases from 0.3 to 0.8,the radiant heat flux on the vane increases,and the radiant heat flux in some areas of the suction surface and pressure surface increases by one time.The effects of wall emissivity and inlet temperature on the vane temperature load and heat flow load are quite uniform.The influence of inlet pressure and blackbody radiation temperature on the thermal load of the trailing edge,leading edge,and pressure surface of the vane is much greater than in other areas.An empirical criterion relation of radiant heat transfer was proposed,which takes total inlet temperature,blackbody radiant temperature,excess air coefficient,and wall emissivity as independent variables and radiant heat flux as a dependent variable.The fitting results of the empirical relation are obtained,and the relative errors are all less than 5%by calculating the fitting accuracy.

关 键 词：热负荷 对流辐射 涡轮叶片 数值模拟 灰气体加权和模型 经验准则关系式 航空发动机 

分 类 号：V232.4[航空宇航科学与技术—航空宇航推进理论与工程]