Estimation of discharge and its distribution in compound channels

作     者：MOHANTY Prabir Kumar KHATUA Kishanjit Kumar 

作者机构：Department of Civil EngineeringNational Institute of TechnologyRourkelaOrissaIndia 

出 版 物：《Journal of Hydrodynamics》 (水动力学研究与进展B辑（英文版）)

年 卷 期：2014年第26卷第1期

页      面：144-154页

核心收录：

学科分类：08[工学] 081501[工学-水文学及水资源] 0815[工学-水利工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 0701[理学-数学] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：support received by the second author from DST India(Grant No.SR/S3/MERC/066/2008) 

主　　题：compound channels boundary shear stage-discharge relationship discharge distribution friction factor 

摘      要：Results of research into a compound channel having width ratio （a） in excess of 11 are presented in the form of boun-dary shear distributions across the compound cross section. New relationship is derived between the percentage of shear carried by the flood plains （%S fp ） and the percentage of area occupied by the flood plains （%Afp ） . The equation so derived is taken as the basis to develop a new methodology to predict the stage discharge relationship specifically for wide compound channels using Darcy＇s friction factor （ f ） for the main channel and flood plain regions. The methodology also is used for compound channels with smaller width ratios by applying the appropriate relation for %S fp derived earlier by different researchers and seems to work well. Next, as a corollary to the methodology, separate formulae are proposed to estimate flow distribution in main channel and flood plain regions. The proposed method and its corollary are tested for their validity against well-published small-scale data series of pre-vious researchers along with some large-scale data series from EPSRC-FCF （A-Series） compound channel experiments and very good agreement is observed between the measured values and predicted values for total flow as well as zonal distribution of flow. The methodology is also applied to some compound river section data published in literature and is found to serve well the purpose of predicting flow in real world application. This new method gives the least RMS value of error for discharge prediction compared with some other well-known methods used for estimating stage-discharge relation in compound channels by considering all data sets.