In this paper, the validity of the simulation method for earth ground heat storage, in which the water chemical potential (Gibb's free energy) relative to the free water and the temperature are used as the moisture and heat transfer potential, is examined in more detail. Specifically, the effects of advection on the thermal efficiency of the thermal well in the aquifer are analyzed numerically. The advection in the saturated domain is investigated in more detail because the effects in this condition are greater than those in the unsaturated domain. It concludes that the effects of advection caused by underground water flow and natural convection on the thermal efficiency of the thermal well can be neglected for practical purposes in the case of level ground.
