气冷涡轮叶片传统热分析中热边界条件的影响

以MarkII气冷涡轮叶片为研究对象,考察了换热系数分布对叶片外表面温度分布的影响。首先分别以温度和换热系数实验值作为热边界条件验证了固体导热计算方法和CFD程序的有效性,然后分析了6种典型热边界条件下的叶片外表面温度分布,并与实验值进行对比。由分析结果可知:叶片外表面温度与换热系数紧密关联,经验关联式(层流、湍流)条件下预测得到的温度偏差较大,当换热系数由能考虑边界层转捩影响的CFD计算得到时,预测得到的温度与实验值较为接近。

Influence of Thermal Boundary Conditions in Conventional Heat Transfer Analysis of an Air-Cooled Turbine Vane

The influence of heat transfer coefRcient distribution on the external surface temperature distribution of an air-cooled turbine vane is investigated.First,the heat conduction computation method and CFD procedure are respectively validated with the thermal boundary condition of the measured temperature distribution and heat transfer coefficient distribution.Then the external surface temperature distributions at 6 typical thermal conditions are compared with the experimental data.The results show that the distributions of external temperature and the distributions of heat transfer coefRcient are closely related.When the heat transfer coefRcient is derived from empirical correlations(laminar or turbulent),the predicted temperature distribution differs a lot from the experimental data.When the heat transfer coefficient is computed by using CFD method with transitional turbulence model,the predicted temperature is closer to the experimental data.