关于绕任意机翼非定常流动的一种无条件稳定的欧拉方程解

本文给出了绕二维与三维刚性或弹性振动机翼非定常无粘流动的欧拉方程解。首先利用Jameson的有限体积方法建立了求解欧拉方程的Runge-Kutta方法。为了提高受Runge-Kutta法稳定性限制的时间步长,文中采用了变系数的残值光顺方法。该方法避免了常系数残值光顺引起局部流场损失较大的问题。同时可在保证原计算格式精度要求下,大幅度提高计算时间步长,从而提高了计算效率。文中以二维与三维矩形机翼为例,分别对其在跨音速流场中作则性或弹性振动的非定常气动力进行了计算,研究了不同振动频率对流动产生的影响。部分计算结果与相应实验结果进行了比较。结果证明本方法是可靠的,可以用于求解绕任意运动机翼非定常流动问题。

Unconditional Stable Solutions of the Euler Equations for Two and Three-D Wings in Arhitrary Motion

The work presented here shows the unsteady inviscid results obtained for the two-and three-dimensional wings which are in rigid and flexible oscillations. The results are generated by a finite volume Euler method.It is based on the Runge-Kutta time stepping scheme developed by Jameson et al.To increase the time step which is limited by the stability of Runge-Kutta scheme,the implicit residual smoothing which is modified by using variable coefficients to prevent the loss of flow physics for the unsteady flows is engaged in the calculations.With this unconditional stable solver the unsteady flows about the wings in arbitrary motion can be received efficiently.The two-and three-dimensional rectangular wings which are in rigid flexible pitching oscillations in the transonic flow are investigated here,some of the computational results are compared with the experimental data. The influence of the reduced frequency for the two kinds of the wings are researched.All the results given in this work are reasonable.