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本文采用大涡模拟(LES)方法对壁面换热边界条件下有压力梯度的分离边界层流动问题进行了数值模拟研究,对不同壁面热边界条件下分离边界层进行了统计特性及瞬态流场分析.结果表明:与绝热壁面条件相比,等温冷壁面条件(0.8倍来流总温)下附着边界层内的速度剖面比绝热壁面更加饱满,边界层形状因子降低、分离泡也被显著抑制,其时均分离泡尺寸无论是在流向还是法向均更小;等温冷壁面条件下分离剪切层展向涡脱落的位置提前,展向涡卷起的频率降低,分离剪切层内相干结构尺度整体减小,促使分离边界层转捩加速和再附位置前移.“,”Separated boundary layer under different wall heat transfer and pressure gradient conditions are investigated by using large eddy simulation (LES). The statistic characteristics and the instantaneous flow field of the separated boundary layer under different wall heat transfer conditions are analyzed. The results show that the velocity profile of the separated boundary layer under the cooled isothermal wall condition (the wall temperature being 0.8 times of the inflow temperature) is fuller than that under the adiabatic wall condition. The shape factor of the boundary layer is reduced and the separation bubble is also significantly suppressed. It is also found that the position of the spanwise vortex shedding from separated boundary layers moves upstream under the cooled isothermal wall condition. Moreover, the cooled isothermal wall condition can decrease the frequency of the large scale spanwise vortex rolled-up, and reduce the scales of the spanwise vortex on the separated shear layer, which accelerates the transition process of the separated shear layer and make reattachment point move upstream.