Establishment and simulation of heat and moisture transfer model outside the borehole based on finite length cylindrical surface

Established the vertical ground source heat exchanger´s finite length cylindrical surface heat and moisture transfer model based on the mass and energy conservation theory. Simulated the non-steady-state heat and moisture transfer of soil around the ground source heat exchanger with COMSOL multi-physics coupling analysis software, and analyzed the influence in temperature and moisture field outside the borehole caused by the heat and moisture transfer in different soil thermal properties and initial moisture contents conditions.