Numerical simulation of freezing process in geothermal boreholes using solar heat injection

The ground thermal energy as a clean and sustainable energy source has got significant attention nowadays. Several strategies and hybrid configurations are proposed to harvest the geothermal energy for air conditioning and industrial purposes. The possibility of moist soil freezing in the vicinity of borehole tubes is known to be the source of several benefits as well as difficulties. The high storage capacity during the freezing process in contrast to the structural damage are the major advantages and disadvantages of the thawing phenomenon. In the present study, the numerical simulation of freezing process around the U-tube configuration of boreholes accompanied by the solar energy injection as the auxiliary heat source is investigated. Lower values of cold stream temperature, results in higher amount of recovered heat while increasing the injected heat temperature intensifies the heat regaining.