Abstract
The proposed heat transfer theory of the Bore-hole Heat Exchange System (BHES), incorporating the thermal interaction between a bore-hole heat exchange pile and groundwater flow, could reproduce the measured fluid temperature distribution along a heat exchange pile during the operation and in the following fluid temperature recovery period. From the numerical simulation, the proposed model predicted the enlargement and disappearance of groundwater temperature variation associated with the operation of heat injection and extraction, and showed that the surviving period of the temperature variation is shorter than two months after ceasing the operation. Finally it was seen that the performance of heat injection and extraction is remarkably improved with the increase in the Peclet number, Pe, at the upstream side element contiguous to the heat exchange pile for Pe≤5.
