抛石输运行为的连续时间随机行走模型应用  

Application of continuous time random walk model for riprap transport behavior

作　　者：王茂枚 李志鹏[3] 赵钢 鲁程鹏 孙洪广[3] WANG Mao-mei;LI Zhi-peng;ZHAO Gang;LU Cheng-peng;SUN Hong-guang(Hydraulic Science and Research Institute of Jiangsu Province,Nanjing 210017,China;College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China;College of Mechanics and Materials,Hohai University,Nanjing 211100,China)

机构地区：[1]江苏省水利科学研究院,南京210017 [2]河海大学水文水资源学院,南京210098 [3]河海大学力学与材料学院,南京211100

出　　处：《水道港口》2019年第5期565-571,共7页Journal of Waterway and Harbor

基　　金：国家自然科学基金面上项目(11572112);国家自然科学基金面上项目(11772121);江苏省水利科技项目(2017009)

摘　　要：文章研究河道抛石的反常输运行为,应用连续时间随机行走模型,模拟抛石在河床上的运动行为。通过等待时间和跳跃步长的分布形式反映河床结构的异质性,从粒子随机运动角度解释了抛石在河道中反常输运的物理机理。应用蒙特卡罗模拟方法,直观展示了抛石输运过程中粒子在不同时刻下的空间分布情况。模型构建了单个粒子运动行为和宏观抛石输运现象之间的联系,对比实验结果验证了模型捕捉抛石反常输运现象的有效性,理论结果与实验高度吻合。分析结果表明,抛石运动过程中等待时间和跳跃步长的“宽”分布是导致抛石产生反常输运现象的主要原因。Anomalous transport behavior of riprap in rivers was studied by using the continuous time random walk(CTRW)model in this paper.The physical mechanism of anomalous transport behavior is explained from the particle stochastic motion by the distribution of waiting times and jump steps.Monte Carlo simulation method was used to visualize the spatial distribution of particles in the transport process of riprap.The model established the relationship between individual particle motion behavior and macroscopic transport behavior,and compared with the experimental results.The theoretical results are in good agreement with the experimental results.The results show that the CTRW model can well capture non-Fickian transport behaviors using the spread distribution of the waiting times and jump steps.

关 键 词：抛石 连续时间随机行走 重尾分布 蒙特卡罗模拟 反常输运 

分 类 号：U617[交通运输工程—船舶及航道工程]