边界条件对三维空腔流动振荡的影响

基于全隐式无分裂方法,数值求解三维非定常雷诺平均的N av ier-S tokes方程,紊流模型采用修正的B-L代数模型。运用此方法,本文数值模拟了三维开式空腔的超声速、跨声速、亚声速流动。研究了空腔口处剪切层的非定常运动现象,着重探讨了入口边界条件对三维空腔流自持性振荡的影响。数值计算结果表明,与层流速度型相比,入口条件为紊流速度型和特征边界型得到的结果能够吻合。

Influence of Boundary Condition on 3-D Cavity Flow-Induced Oscillations

Based on the fully implicit unfactored method,a numerical solution of three-dimensional unsteady Reynolds-averaged Navier-stokes(URANS) equations is presented,in which the revised Baldwin-Lomax turbulent model is employed.Using the above method,numerical simulations are implemented for supersonic,transonic and subsonic flows around three-dimensional open cavities.The self-sustained oscillatory motion of the shear layer is studied and visualized,which emanates from the leading edge of the cavity.The influence of the inlet boundary condition on the oscillation is discussed,and several important conclusions are drawn. The comparison of numerical calculations demonstrates that the turbulent profile and characteristic boundary at the inlet can lead to better results than the laminar profile.