The present study aims to investigate the performance of multiple-tube ground heat exchangers (GHEs). Theudmultiple-tube GHEs with a number of pipes installed inside the borehole were simulated. Thermal interferences between theudpipes and performance of multiple-tube GHEs are discussed. Increasing the number of inlet tube in the borehole increases theudcontact surface area and then leads to increase of heat exchange with the ground. However, ineffective of heat exchange in theudoutlet tube caused by thermal interferences from the inlet tube reduces the heat exchange rate for the GHEs. The GHEudperformances increase of 9.1 % for three-tube, of 13.6 % for four-tube, and of 20.1 % for multi-tube compared with that of theudU-tube. The four-tube and multi-tube GHEs which consist of four pipes as heat exchange pipes where the multi-tube GHEudprovides better performance than that of the four-tube GHE. This fact indicates that thermal interferences between the pipesudaffect the performance. Thermal interferences between the pipes should be considered
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