高超声速滚转阻尼导数数值模拟

Numerical simulation of damping-in-roll derivatives of blunt cone for hypersonic flow

采用非定常 Navier-Stokes方程描述物体简谐振动流场 ,并在 Etkin理论下给出绕定轴转动时滚转阻尼导数的计算公式 ,定常流场的计算采用空间二阶精度的交替方向隐式分解的 NND格式 ,非定常流场的计算采用时、空二阶精度的 Runge-Kutta多步格式 ,采用代数方法生成物体静、动网格。最后给出高超声速下钝体外形滚转阻尼导数的计算结果 ,以及滚转力矩系数随瞬时振幅的变化曲线。

In this paper, the harmonic oscillating flows were solved by unsteady Navier Stokes equations, and the calculation method of damping in roll derivatives was presented under the Etkin's theory when body oscilated around a fixed axis. Steady flows are calculated by alternating direction implicit NND scheme. Unsteady flows are calculated by four stage Runge Kutta method, which is a second accuracy scheme in time and space. The grids at steady unsteady calculation were generated by algebra method. Finally, the calculation results of blunt body including damping in roll derivatives,rolling moment coefficient and side force coefficient have been proposed at hypersonic condition.