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采用一种混合大涡模拟/雷诺平均Navier-Stokes(LES/RANS)模拟方法结合三阶加权基本无振荡(WENO)格式对马赫数为2.88的压缩斜坡流动进行了数值模拟,并采用“回收/调节”方法生成入口湍流脉动边界条件.当采用固定入口边界条件时,湍流边界层会缺乏合理的湍流能量,使之抵抗逆压梯度的能力减弱,会严重高估分离区的大小;而当采用“回收/调节”方法时,可以在10倍来流边界层厚度的距离内激励起湍流大尺度结构,计算得到的流场能够再现激波/湍流边界层干扰流场的非定常特性,时间及展向平均壁面压力和试验值吻合较好.
A mixed large-eddy simulation / Reynolds-averaged Navier-Stokes (LES / RANS) simulation method combined with the third-order weighted basic oscillationless (WENO) format was used to simulate the compression ramp flow with a Mach number of 2.88. Turbulent boundary layer will lack reasonable turbulent energy to make it less resistant to the pressure gradient and seriously overestimate the size of the separation zone when the fixed inlet boundary conditions are used. When using the “recovery / conditioning” method, turbulent large-scale structures can be excited within a distance of 10 times the thickness of the boundary layer, and the calculated flow field can reproduce the unsteady flow fields of the shock / turbulent boundary layer Characteristics, time and direction of the average wall pressure and test values match well.