COMSOL平台在城市地下多种资源相互影响分析中的应用

针对系统动力学方法在地下资源相互影响问题分析中存在的不足，引入了多孔介质多场耦合理论，以地下水源热泵形式浅层地热能资源开发的假想模型为例，运用COMSOL平台建立了温度场-渗流场-应力场耦合的数值模型，对比了地下水源热泵运行前后和对调抽/回灌井前后区域地下渗流场、地温场和应力场的变化情况。结果表明：地下水源热泵运行前后抽水井和回灌井周边的渗流场发生了显著改变，10 a之后抽水井的水温由初始的约21℃下降至约17℃，并呈现出继续下降的趋势，区域地面沉降量达2 m左右；对调抽/回灌井后，抽水井温度的下降幅度由之前的4.0℃变为不到0.5℃。COMSOL平台在地下多种资源相互影响分析及其优化利用方面展示出良好的应用潜力。

Application of COMSOL Platform in Analysis of Interaction of Urban Underground Multiple Resources

Aiming at the shortcomings of the system dynamics method in the analysis of the interaction of underground resources, the multi-field coupling theory of porous media was introduced. Taking the hypothetical model of shallow geothermal energy resource development in the form of GSHP as an example, a coupled numerical model of temperature field, seepage field and stress field was established by using the COMSOL platform, and the changes of regional multiple physical fields before and after the GSHP operation and the adjustment of pumping and recharging wells were compared. The results show that the seepage field around the pumping well and recharging well changed significantly after the operation of groundwater source heat pump. After 10 a, the water temperature of the pumping well dropped from the initial 21 ℃ to about 17 ℃, and the regional land subsidence was about 2 m. After the pumping and recharging wells were reversed, the temperature of the pumping well decreased from 4.0 ℃ to less than 0.5 ℃. All these indicate that the COMSOL platform has good application potential in the interactive analysis and optimal utilization of various underground resources.