紧致格式数值模拟超音速粘性绕流问题

通过数值求解可压Navier-Stokes方程的方法计算了球锥粘性绕流问题。方程中粘性项按通常办法逼近,为改善收敛速度利用了文1,2]中之算子附加修正方法。方程中之流向导数利用了四阶精度的紧致差分。这是由于该方向上流动参量光滑和边界条件易于处理的缘故。在法向方向上利用了中心差分。对差分方程之隐式部分利用了近似因式分解法。由于选用了文3]中之特殊Jacobiall系数矩阵分裂法而使计算工作量大为减少。用这种方法计算了超音速粘性绕流问题。计算结果与实验结果相符很好。

NUMERICAL SIMULATION OF COMPACT SCHEMES IN SUPER-SONIC VISCOUS FLOWS

Supersonic viscous flow around a sphere-cone is simulated numerically by solving the compressible Navier-Stokes equations.The viscous part of the equations is treated using correction with operator addition The normal derivatives of the inviscid part are approximated with central difference.The streamwise derivatives are approximated with compact difference.The compact scheme has fourth order accuracy.Jacobian Matrix splitting and approximate factorization are used for solving obtained implicit difference equations.With special chosen matrix splitting the solutions of the implicit difference scheme can be expressed explicitly.The scheme used in present paper has advantages of both implicit and explicit schemes,and the comparison of the computed results with that in reference 7] is satisfactory.