摘要
针对推移质输沙率公式难以兼顾高、低输沙强度计算的不足,提出结构上考虑推移质泥沙滑移及跃移特征的输沙率计算公式.基于无后效Markov随机理论,通过改进泥沙状态转化概率矩阵,优化了泥沙随机交换过程的描述.综合考虑床面遮蔽、水流脉动特征及床面泥沙运动特征的影响,从理论受力分析及概率统计角度,确定了床面推移质泥沙数量.通过引入推移质泥沙滑动、跃移平均运动速度,建立基于泥沙随机交换过程及不同推移形式的推移质输沙公式.最终计算结果与不同输沙强度下的试验及现场实测结果吻合较好,表明公式能兼顾高、低推移质输沙强度的计算,可应用于工程分析.
A new bedload transport rate formula which considered the saltation load motion and the contact load motion was proposed.This formula overcame the shortage of present formulas whose accuracy mostly couldn’t be both acceptable when calculating the bedload transport rate under high and low flow dynamics.The finite state Markov process was used to describe the stochastic sediment interchanges.The sediment transform probability was modified for better description of sediment interchanges.According to a comprehensive consideration of the exposure angle,turbulence and the characteristics of bed sediments,the amounts of bedload was determined by the force analysis and the probabilistic statistics.After that,the new formula based on the stochastic sediment interchanges and the different motion patterns was derived by combining the saltation velocity and the slide velocity of bedload.Computations from this formula agree with both the results from indoor experiments and the in-situ observations,which cover the high and low flow dynamics.These agreements indicate this new formula could be used to estimate the bedload transport rate under different flow dynamics.
作者
沈淇
顾峰峰
万远扬
戚定满
SHEN Qi;GU Fengfeng;WAN Yuanyang;QI Dingman(Department of Hydraulic Engineering,Tongji University,Shanghai 200092,China;Shanghai Estuarine and Coastal Science Research Center,Shanghai 201201,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2023年第3期599-610,共12页
Journal of Basic Science and Engineering
基金
国家重点研究发展计划项目(2017YFC0405403,2016YFC0402101)
关键词
推移质输沙率
泥沙交换
MARKOV过程
滑移
跃移
概率统计分析
bedload transport rate
sediment interchange
Markov process
contact load motion
saltation load motion
probabilistic statistical analysis
