A STUDY ON THE METHOD OF SIZING THE BOREHOLE LENGTH FOR THE GROUND HEAT EXCHANGERS
WEI Xin-hua;TANG Chang-fu;YU Xian-zhong;Institute of Exploration Research of Bureau of Coal Geology of Anhui Provinc;Hefei Research Center of Shallow Geothermal Engineering and Technology;
Sizing the borehole length of ground heat exchangers(GHEs) is the key of designing for the ground source heat pump system. To regulate the method of sizing the borehole length for GHEs from the "Technical code for ground-source heat pump system" requirement, borehole length calculation and checking calculation and simulation are presented through a case study of a ground source heat pump project in Hefei. Results indicate that the thermal interference has a great influence on the borehole length of GHEs. Without considering the thermal interference the borehole length will be smaller. Due to the effect of the heat accumulation underground,the average fluid outlet temperature of ground heat exchanger will increase gradually year by year. Simulation verification results show that the borehole length of GHE can meet the requirement of the technical code.