Numerically quantifying the relative importance of topography and buoyancy in driving groundwater flow

作     者：YANG JianWen 1,2,FENG ZuoHai 1,LUO XianRong 1 & CHEN YuanRong 1 1 Faculty of Earth Sciences,Guilin University of Technology,Guilin 541004,China 2 Department of Earth and Environmental Sciences,University of Windsor,Windsor,Ontario,N9B 3P4,Canada 

作者机构：Faculty of Earth Sciences Guilin University of Technology Guilin China Department of Earth and Environmental Sciences University of Windsor Windsor Canada 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2010年第53卷第1期

页      面：64-71页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the Program to Sponsor Teams for Innovationin the Construction of Talent Highlands in Guangxi Institutions of Higher Learning the Natural Sciences and Engineering Research Council of Canada (NSERC) through a Discovery Grant to Yang Jianwen (Grant No.RGPIN 261283) National Natural Science Foundation of China to Feng Zuohai (Grant No.40772126) 

主　　题：hydrothermal flow free convection forced convection topography buoyancy finite element modeling 

摘      要：Both topography and buoyancy can drive groundwater flow;however,the interactions between them are still poorly *** this paper,the authors conduct numerical simulations of variable-density fluid flow and heat transport to quantify their relative *** finite element modeling experiments on a 2-D conceptual model reveal that the pattern of groundwater flow depends largely upon the relative magnitude of the flow rate due to topography alone and the flow rate due to buoyancy *** fluid velocity due to topography is greater than that due to buoyancy at large water table gradients,topography-driven forced convection overwhelms buoyancy-driven free convection .When flow velocity due to buoyancy is greater than that due to topography at small water table gradients,mixed free and forced convection takes *** this case,free convection becomes dominant,but topography-driven flow still plays an important role since it pushes the free convection cells to migrate laterally in the downhill ***,hydrothermal fluid flow remains changing periodically with time and no steady state can be *** presence of a low-permeability layer near the surface helps eliminate the topography effect on the underlying free convection.