DSMC方法下给定热流边界条件的实施

本文详细讨论了DSMC方法中流体温度、能量及边界热流的统计方法,发展了一种从边界热流求得与壁面碰撞分子反射速度的方法。该方法被称为逆温度抽样算法(ITS,Inverse Temperature Sampling)方法。在此基础上,本文发展了DSMC方法中壁面处给定热流边界条件的实施方法。计算结果表明: ITS方法能准确抽样反射分子的特征温度,进而求得分子反射速度。基于该方法的给定热流边界条件可以准确求得壁面处温度分布,以及流场内的压力、速度。

IMPLEMENTATION OF HEAT FLUX SPECIFIED BOUNDARY CONDITIONS IN DSMC METHOD

The statistical method in DSMC method for the fluid temperature, energy and boundary heat flux is discussed. An Inverse Temperature Sampling algorithm, with which the reflected velocity of the molecules colliding with wall could be calculated from boundary heat flux, is proposed. Further, an implemental method under heat flux specified boundary conditions in DSMC is developed. The numerical results show that the proposed algorithm could accurately sample the characteristic temperature of the reflected molecules, and the reflected velocity could be obtained accordingly. The temperature distribution at wall boundary as well as the pressure and velocity of the fluid can be accurately calculated by means of implementation of heat flux specified boundary conditions based on ITS method.