基于用高斯分布生成管道的岩溶地下水流数值模拟  

Numerical Simulation of Groundwater Flow in a Karst Area with Conduits Generated by Gaussian Distribution

作　　者：刘国东[1,2] 杜成鸿 侯杰 杨梦溪 陈宇 谢杨 Liu Guodong;Du Chenghong;Hou Jie;Yang Mengxi;Chen Yu;Xie Yang(College of Water Resource&Hydropower,Sichuan University,Chengdu 610065,China;State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学水利水电学院,成都610065 [2]四川大学水力学与山区河流开发保护国家重点实验室,成都610065

出　　处：《吉林大学学报（地球科学版）》2024年第2期592-603,共12页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(52379071)。

摘　　要：为更精确地模拟岩溶区地下水运动,以贵州省黔西南普安县某岩溶水文地质单元为研究区,用基于有限单元法的FEFLOW软件建立研究区岩溶管道等效多孔介质耦合地下水流数值模拟模型。模拟中,在地质条件控制下应用高斯随机分布生成地下暗河的管道,用非稳定三维地下水运动的偏微分方程描述等效多孔介质水流运动,用Manning-Strickler方程描述管道水流运动,将导水断层处理为强渗透条块,将落水洞汇水范围的降水入渗系数设置为1,将泉水处理为定水头的抽水井。流场模拟结果显示,25个观测点计算水位与实测水位关系的决定系数可达到0.9985,纳西效率系数达0.9982,极接近于1;表明基于这些处理建立的地下水模拟模型反映了岩溶地下水运动特征,具有较强的仿真能力,可用于提高岩溶区地下水资源评价精度。In order to simulate the groundwater movement in the karst area more accurately,a karst hydrogeological unit in Pu’an County,southwest Guizhou Province was taken as the research area.The FEFLOW software based on the finite element method was employed to establish a numerical simulation model that couples karst conduits with equivalent porous media for groundwater flow in the area.Gaussian random distribution was employed to generate conduits for underground rivers controlled by the geological conditions such as fault,fissure,fracture etc.The water flow in the equivalent porous medium was described by the partial differential equation of the 3 D transient flow,and the water flow in the conduit was described by the Manning-Strickler equation.The water conducting fault is treated as a strong permeable block,the infiltration coefficient of rainfall in the catchment areas of the sinkhole is set to 1,and the spring is treated as a pumping well with a constant head in the numerical model.The simulation results showed that the determining coefficient of the relationship between the calculated water level and the measured water level at 25 observation wells can reach 0.9985,and the Nash-Sutcliffe efficiency coefficient reaches 0.9982,which is very close to 1.It shows that the groundwater simulation model based on these treatments reflects the characteristics of karst groundwater movement and has strong simulation ability,which can be used to improve the evaluation accuracy of karst groundwater resources.

关 键 词：岩溶地下水 地下暗河 FEFLOW 地下水数值模拟 高斯分布 

分 类 号：TV221[水利工程—水工结构工程]