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本文通过求解三维Reynolds-Averaged Navier-Stokes(RANS)和Spalart-Allmaras紊流模型数值研究了跨音速涡轮静叶上端壁结构对动叶顶部气动换热特性的影响.数值预测得到的动叶中径处压力分布与实验数据吻合良好,从而验证了该数值方法的可靠性.本文研究结果表明:静叶上端壁结构对动叶顶部前缘处的流动换热特性有显著影响,对靠近尾缘处的流动换热没有影响;静叶端壁为S型上端壁时叶顶平均换热流密度要低于采用常规端壁,且通流效率高于采用常规端壁;靠近尾缘区域的流动换热特性受间隙内斜激波的影响显著,由于斜激波和叶顶表面边界层的相互作用及斜激波在叶顶表面和端壁面之间的反射,导致靠近尾缘处的叶顶表面存在条状分布的高热流密度区域.“,”Effects of the shroud profile of the stator vane on the flow and heat transfer performance of the blade tip were numerically investigated using three dimensional Reynolds-Averaged Navier-Stokes (RANS) and Spalart-Allmaras turbulent model.The accuracy of the utilized numerical approach was validated by comparing the CFD predictions and the experimental pressure coefficients at the midspan.The numerical results showed that the shroud profile of the stator vane has significant influence on the flow and heat transfer performance of the frontal blade tip,meanwhile,little influence on the aft blade tip.The case with “S” shaped shroud profile has a lower level of the averaged heat flux on the blade tip than that of the case with nominal shroud.However,the flow efficiency of the case with “S” shaped shroud profile is obviously enhanced in comparison with the nominal shroud.The heat transfer performance on the aft blade tip is greatly affected by the obligue shock inside the tip gap.The high heat flux stripe is located near the pressure side blade tip due to the refection of the obligue shock between the shroud and blade tip.