挟沙水流中悬浮颗粒的漂移—扩散方程  

Drift-diffusion equation for suspended particles in sediment-laden flow

作　　者：钟德钰[1] 王光谦[1] 王士强[1] 

机构地区：[1]清华大学水利系,北京100084

出　　处：《水动力学研究与进展（A辑）》2001年第1期51-55,共5页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金资助项目! ( 598790 0 6和 59890 2 0 0 )

摘　　要：本文基于固液两相流动双流体模型的基本方程推导得到了挟沙水流中悬浮颗粒的漂移—扩散方程。该方程表明 ,除重力外 ,作用在颗粒上的升力、虚拟质量力、Basset力等 ,以及颗粒间相互作用都会影响颗粒浓度分布。对明渠中悬浮颗粒浓度垂线分布分析结果表明 ,在床面附近有较大值的升力是使得悬浮颗粒浓度在趋近床面时增大趋势趋缓 ,甚至趋向于零的重要因素 。Based on the basic conservation equations of solid liquid two-phase flow, a new drift-diffusion equation was derived in this paper. It shows that besides the gravity force, other forces such as the lift forces, the Basset force and the interaction between particles play a significant role on sediment concentration distribution. The analysis of the concentration distribution indicates that the lift forces which have large value near the bed decelerate the tendency of sediment concentration increment, ever making the concentration vanish when approaching the bed surface if the lift forces are large enough. A comparison between measured concentration distribution in flume and the present results shows that they agree well.

关 键 词：漂移-扩散方程 升力 浓度分布 挟沙水流 悬浮颗粒 

分 类 号：TV142.3[水利工程—水力学及河流动力学]