异重流潜入现象探讨Ⅰ:水槽实验与理论分析成果回顾  

Investigation of density current plunging Ⅰ: Review of previous flume experiment works and theoretical analysis

作　　者：范家骅[1] 祁伟[1] 戴清[1] FAN Jiahua;QI Wei;DAI Qing(China Institute of Water Resources ＆ Hydropower Research, Beijing 100048, China)

机构地区：[1]中国水利水电科学研究院,北京100048

出　　处：《水利学报》2018年第4期404-418,共15页Journal of Hydraulic Engineering

摘　　要：本文对异重流潜入现象中各种潜入点水槽实验、理论分析和数值计算成果进行回顾,并探讨不同进口水沙条件下异重流潜入点的水沙特性、潜入点与其下游异重流水沙因子的关系,全文以两篇分述。本篇介绍各家用浑水、盐水和冷水进行实验,在已知进口水沙(盐水或冷水)条件下,获得潜入点断面的密度Froude数Fp,且Fp为某一定值;水库壅水区Fp值在0.5~0.8之间,引航道口门处Fp在0.25左右。在潜入点理论分析、模型数值计算方面,探讨了潜入点Fp值同掺混系数、阻力系数以及潜入点下游异重流深度hd与潜入点水深Fp之比的关系;各家建立不同概化图形并应用能量、动量方程进行分析,求得不同形式的Fp表达式;有学者利用紊流水沙模型进行数值计算与水槽实验的Fp值或hp进行对比,获得基本符合实际的结果。This paper reviews previous flume experiment works and theoretical analysis of density currentplunging,then explores the value of the densimetric Froude number Fpat the plunge point and the relation-ship of the value of Fpwith the depth of the density current hd. The paper contains two parts. Here thefirst part presents a review of experiments of plunge point with turbid,saline or cold water inflow. Experi-mental value of Fp=0.5~0.8 in reservoir backwater region, and Fp=0.1~0.3 in navigation guiding channelswere obtained by many researchers. Then a summary was made for the previous theoretical analysis and thenumerical analysis of turbulent flow models for plunge point prediction. Various authors investigated the pa-rameter Fpwhich varies with the mixing coefficient, friction coefficient and the ratio of the density currentdepth hddownstream of the plunge point to the plunge point depth hp. Several schematic diagrams were de-veloped,and analyses were made applying energy equation and momentum equation,and obtained some dif-ferent types of Fpexpressions. Some investigators used the method of turbulent models with numerical calcu-lation to determine the value of hpor Fp. Comparison was made with the experiment values of hpor Fp.The previous theoretical analysis results of density current plunge point were used to compare with the writ-er＇s investigation results by theoretical analysis.

关 键 词：异重流 异重流潜入 水槽实验 理论分析 

分 类 号：TV145.2[水利工程—水力学及河流动力学]