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针对非线性涡粘性模式在求解三维湍流边界层流动时的不足 ,本文从压力 变形率关联项中的快速项出发 ,考虑流动非均匀影响 ,在显式代数应力模式的雷诺应力表达式中引入了反映雷诺应力“松弛”效应的速度二阶导数项 ,构造了一个新的非线性涡粘性模式。通过对典型算例———翼体角隅流动的计算结果表明 ,新模式能较好地再现出三维湍流边界层内雷诺切应力方向的发展滞后于速度梯度方向发展这一流动特性。
Aiming at the shortcomings of nonlinear eddy viscosity model in solving the problem of three-dimensional turbulent boundary layer flow, this paper, based on the fast term of the pressure deformation rate, considering the non-uniform flow, introduced the Reynolds stress expression in explicit algebraic stress mode A second nonlinear eddy viscosity model is constructed based on the second-order derivative of velocity that reflects the “relaxation” effect of Reynolds stress. The calculation results of a typical example --- wing-body corner flow show that the new model can better reproduce the development of the Reynolds stress direction in the three-dimensional turbulent boundary layer lagging behind that of the velocity gradient direction.