计算跨音速N─S方程组的二阶隐式矢通量分裂格式

TWO ORDER IMPLICIT FLUX VECTOR SPLITTING SCHEMES FOR TWO DIMENSIONAL TRANSONIC VISCOUS FLOW

提出了一种二阶精度隐式矢通量分裂单步差分格式并用于求解时间平均Ｎ－Ｓ方程组。与传统方法相比，该方法是Ｊａｃｏｂｉ谱半径格式和无近似因子分解。数值试验表明：该方法具有精度高、计算量小和收敛快等优点。在平面叶栅和扩压器进气道的跨音速流场的求解中，较好地捕获了激波、分离等现象。

A one step two order accuracy Implicit Flux Vector Splitting(IFVS)scheme is provided to solve the time average N S equations.Compared with conventional methods of implicit schemes,the present method is a Jacobian spectral radius scheme and a non approximate factorization scheme.Numerical calculations demonstrate clearly that it has obvious superiority in aspects of accuracy,robustness,calculation time and convergence.In the cases of two dimensional transonic cascade flows and diffusers,shock wave and separation are exactly captured,which shows good agreement with experimental data.