Research on the influence of underground seepage on regional heat accumulation of ground source heat pump heat exchanger

Abstract

During the long-term operation of the ground source heat pump system, the temperature imbalance of the rock and soil around the heat exchanger results in the deterioration of the performance of the ground source heat pump system. Through previous projects, it has been found that in the area of underground seepage speed, it is helpful to alleviate the heat or cold accumulation of rock and soil mass around the ground source heat pump system. Based on this, two test sites in Zhangqiu District, Jinan City, Shandong Province, were selected to conduct pumping and irrigation tests to change the underground seepage velocity, determine the flow velocity through isotopic tracer tests, obtain soil thermal physical parameters and simulate heat accumulation through thermal response tests, and establish long-term numerical simulation through Opengeosys to synthesize the conclusion that the seepage velocity increases. The more efficiently the temperature of the rock and soil mass is restored to the initial condition, the more efficiently the heat exchange performance of the buried pipe heat exchanger and the surrounding rock and soil mass is maintained, and the efficient operation of the ground source heat pump system in winter and summer is ensured.