含水层热量运移中自然热对流作用的数值模拟

Numerical Simulation of Natural Thermal Advection in the Process of Heat Transfer in Aquifers

较严密地推导了能够描述含水层热量运移中自然热对流作用的水流方程和热量运移方程,并在此基础上建立了一个三维非线性模型。根据模型的特点,提出综合采用Douglas Brian ADI差分法、特征线法返回技术及改进Picard迭代法求解,并给出了计算步骤。模型及数值方法用于模拟上海第二承压含水层中的一个群井储能试验。试验中的自然热对流作用得到了较好的体现,反映出模型合理可靠,方法有效,结果令人满意。

In this paper, the flow and thermal transport equations for the accurate description of natural thermal advection in the process of heat transfer in aquifers are manipulated and presented. A nonlinear three-dimensional heat transfer model is established as well. According to the characteristics of the model, the DouglasBrian ADI finite difference scheme, the characteristic reverse-tracking technique, and the improved Picard iterative method are proposed to solve it, and the calculation steps are also provided. Finally, the model together with the numerical meth ods are applied to simulate a multi-well ATES (Aquifer Thermal Energy Storage) experiment which was performed in the second confined aquifer in Shanghai. The results are satisfying and the natural thermal advection in the experiment is well represented. This shows that the model is reasonable and reliable, and the proposed methods are quite effective.