推移质运动的随机理论与应用

Stochastic Model of Bed-load Transport in Mountain Rivers:Theory and Applications

陡坡急流条件下的推移质运动常伴有较大幅度的随机变化,这种随机涨落现象在各个时间尺度下普遍存在。由于这种涨落现象的存在,随机理论模型往往更适用于描述这一类问题。为进一步研究推移质运动的随机属性,作者利用包含群体输移机制的Markov随机模型,通过理论和实验方法研究输沙停时的概率密度分布函数(PDF),这些研究揭示出推移质运动中的尺度分离现象。在前人工作的基础上,给出输沙停时PDF理论解的另外一种推导方式推导。与较早的研究相比,该推导更为简洁、直接。该理论解已通过数值和室内实验数据得到了验证。

Bed-load transport process over steep slope is of large fluctuations.This kind of fluctuation widely exists over different time scales.Due to this random behavior,the stochastic model can make a better performance on the description of bed-load transport process than the deterministic one.Based on the result of the early study,an alternative method to derive the theoretical solution was provided.Compared to the early derivation,by using this method the theoretical solution can be straightforward obtained from master equation.This solution was tested well against the numerical simulation and experimental data.