Resistance of the flow over rough surfaces

作     者：Yu Han Shi-yu Wang Jian Chen Shuqing Yang Liu-chao Qiu Nadeesha Dharmasir Yu Han;Shi-yu Wang;Jian Chen;Shuqing Yang;Liu-chao Qiu;Nadeesha Dharmasiri

作者机构：College of Water Resources and Civil EngineeringChina Agricultural UniversityBeijing100083China College of EngineeringChina Agricultural UniversityBeijing100083China School of CivilMining and Environmental EngineeringUniversity of WollongongWollongongAustralia 

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

年 卷 期：2021年第33卷第3期

页      面：593-601页

核心收录：

学科分类：080704[工学-流体机械及工程] 080103[工学-流体力学] 08[工学] 0807[工学-动力工程及工程热物理] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Projects supported by the National Natural Science Foundation of China(Grant No.51979275) This work was supported by the Jilin Province Key Research and Development Plan Project(Grant No.20180201036SF) the Open Research Fund of State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University(Grant No.19R06) the Open Research Project of the State Key Laboratory of Industrial Control Technology,Zhejiang University(Grant No.ICT20021) the Chinese Universities Scientific Fund(Grant Nos.2020TC033,10710301) 

主　　题：Hydraulic radius skin friction form drag friction factor separation zone dead fluid volume 

摘      要：The mechanism of the flow resistance in open channels and pipelines is of vital importance for various critical issues related to the water *** Nikurade’s method of calculating the friction factor is not applicable in some *** is necessary to consider the influence of the vortex volume surrounding the vegetation and to study the hydrodynamic characteristics of the vegetated *** paper analyzes the variation of the vortices created by the surface roughness of different types and different sizes and proposes new definitions of the hydraulic radius and the equivalent roughness *** consideration of the skin friction and the form drag,on the basis of the force balance equation,a novel calculation method is used for the friction factor,and this method is verified by experimental *** hydrodynamic mechanism of the flow resistance revealed in this study may serve as a theoretical basis for hydraulic engineers to calculate the friction factor.