摘要
零剪切应力分割线法和分割线表观剪切应力法是计算河底和河岸水流剪切应力的两种常用方法.为简化分割线表观剪切应力经验表达式,提出了“动量传输-平衡偏离”(momentum transfer-equilibrium deviation,MTED)假设,认为表观剪切应力可由分割线一侧单位时间动量传输与其平衡值的差值来表示.为了确定平衡值,提出了标准断面的概念,所有矩形或者梯形断面都有对应的标准断面.基于MTED假设和标准断面的概念,建立了分割线表观剪切力以及河底和河岸剪切力占总剪切力比重的计算表达式.利用不同实验的200多个数据对不同的计算方法进行了对比分析,结果表明:该文的方法有效改善了计算精度,适用范围广,适用于矩形和梯形断面,以及河岸与河底糙率相同或不同的情况.
Seeking for the“zero shear stress dividing line”and quantifying the apparent shear stress at the interface between adjacent sub-regions are 2 main methods to calculate the riverbed and bank shear stresses.To simplify the empirical expression for apparent shear stresses along the dividing line,a“momentum transfer-equilibrium deviation”(MTED)assumption that the apparent shear stress can be calculated based on the deviation of momentum transportation from its equilibrium value,was proposed.A“standard cross-section”concept was applied to determine the equilibrium value.All the rectangular and trapezoidal cross-sections can be correlated with certain standard cross-sections.Based on the MTED assumption and the concept of standard cross-sections,the empirical expressions for the apparent shear stresses along the dividing line and the bed and bank boundary shear stresses,were established.More than 200 data from different lab experiments were used to verify different methods.The results show that,the proposed method improves the calculation accuracy and can be applied to both rectangular and trapezoidal cross-sections,as well as to both smooth and rough channels.
作者
罗优
朱森林
曹兵
蒋陈娟
LUO You;ZHU Senlin;CAO Bing;JIANG Chenjuan(College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou,Jiangsu 225009,P.R.China;Dongying Water Administration,Dongying,Shandong 257091,P.R.China)
出处
《应用数学和力学》
CSCD
北大核心
2021年第9期915-923,共9页
Applied Mathematics and Mechanics
基金
国家自然科学基金青年科学基金(41806104)。
关键词
表观剪切应力
水流分区
河底阻力
河岸阻力
动量传输
糙率
apparent shear stress
flow partitioning
riverbed resistance
river bank resistance
momentum transfer
roughness
作者简介
通讯作者:罗优(1985-),男,讲师,博士.E-mail:luoyou@yzu.edu.cn.
