碰撞激起沙粒的起跳初速度分布函数

The Probability Density Function Distribution of the Liftoff Velocity in Grain/Bed Collision

本文根据已有粒/床碰撞研究得出的基本定性结论以及组合论的基本原理,给出了风沙流中碰撞激起沙粒的起跳初速度分布函数,该函数服从瑞利分布的形式。以这一起跳初速度分布函数为基础建立风沙耦合跃移运动的基本模型,计算了单宽输沙率等风沙运动机理研究中普遍关心的物理量。将计算结果和已有实验结果对比分析表明,本文给出的起跳初速度分布函数是科学的,这对风沙流中沙粒起跳初速度分布函数给出了一个定性的认识。

Based on some deterministic laws of the grain/bed collision and the constitution theory,aprobability density function distribution of the liftoff velocity is obtained as the Rayleigh distribution.A model between the grains and the wind is suggested in this paper.Then,the windblown sand movement mechanism is discussed as the streamwise sand transport.The comparison with existing experimental results show that the probability density function distribution of the liftoff velocity obtained in this paper is feasible,and a qualitative understanding about the probability density function distribution of the liftoff velocity is obtained.