坡面流层流区动力学特性  

Study of dynamic characteristics of laminar flow zone in overland flow

作　　者：杨苗[1,2] 龚家国 赵勇[1] 赵翠平[1] YANG Miao;GONG Jiaguo;ZHAO Yong;ZHAO Cuiping(China Institute of Water Resources and Hydropower Research,Beijing 100038,China;College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China)

机构地区：[1]中国水利水电科学研究院,北京100038 [2]河海大学水文水资源学院,江苏南京210098

出　　处：《水科学进展》2019年第5期709-718,共10页Advances in Water Science

基　　金：国家自然科学基金资助项目(51209222);流域水循环模拟与调控国家重点实验室自主研究课题(2015ZY01)~~

摘　　要：为完善坡面水流的基础理论研究,基于定床水槽试验,以甘油溶液为试验流体,采用超声波测量技术,进行了4种粗糙度、5种坡度和13种单宽流量条件下的组合试验,研究了坡面流层流区的动力学特性及滚波特征。研究结果表明:在雷诺数为8~160的范围内,流态指数在理论值0.33附近波动,且随粗糙度的增大呈现先增大后减小的变化趋势,在粗糙度为0.10 mm附近达到峰值;阻力系数受坡度和粗糙度影响显著,可较好地由坡度、粗糙度和雷诺数的关系式表示;随着雷诺数的增大,滚波波速和波峰均呈幂函数形式递增,滚波周期大小无明显变化;坡度的增大会使层流失稳临界单宽流量减小,粗糙度的增大会使临界弗劳德数的均值减小。To improve the basic theoretical research of overland flow,this researcher used a fixed-bed flume test and ultrasonic sensor measurement technology to study the hydrodynamic characteristics of laminar flow and roll waves on the slope surface.Glycerol solution was used as test fluid and combined tests were performed under four levels of roughness,five slope gradients and 13 single-width flow conditions.The results show that the flow index fluctuates around the theoretical value of 0.33 for Reynolds numbers ranging from 8 to 160.It first increases and then decreases as the roughness increases.The roughness is around 0.10 mm.The peak is reached,and the drag coefficient is significantly affected by the slope and roughness,which can be expressed as the relationship between slope,roughness and Reynolds number;as the Reynolds number increases,the roll wave velocity and the peak value increase in the form of a power function.There is no readily visible change in the magnitude of the rolling cycle;the increase in the slope causes the layer to lose stability and the critical single-width flow gradually decreases.The increase of the roughness causes the critical Froude number to decrease.The research results can provide theoretical basis for the development of hydraulics and hillside hydrology.

关 键 词：坡面流 流态 阻力规律 滚波 甘油 

分 类 号：S158.1[农业科学—土壤学]