DEVELOPMENT AND VALIDATION OF NUMERICAL MODELS OF BOREHOLE HEAT EXCHNAGER FOR GSHP (DOUBLE U-TUBE TYPE AND CONCENTRIC TUBE TYPE)

Since a GSHP (Ground source heat pump) system uses thermal heat of the ground as a stable source of heat, its high system efficiency is expected to help save energy and reduce CO2 emissions, as well as alleviate the heat island effect because it does not release heat to the atmosphere. In Japan, the concept of GSHP systems began to attrac