Study on the influence of the design method of the ground source heat pump system with considering groundwater seepage

摘要

The identification model of the thermal response test (TRT) equates the actual complex stratified soil with seepage to a homogeneous soil without seepage. In this paper, a three-dimensional dynamic simulation experiment platform for the ground source heat pump system (GSHPS) was established where the equivalence of the TRT and its influence on the long-term performance of the GSHPS with different thermal loads were analyzed. The results showed that there was a big difference of the soil thermal properties between under the actual and equivalent conditions. Under the conditions in this paper, the soil thermal diffusivity under the equivalent condition was 151.16% higher than that under the actual condition, but the difference of short-term heat transfer performance between them was only 2.65%. Under the Harbin, Shenyang and Beijing thermal load, the annual COP in the tenth year in the actual condition decreased by 0.82%, 0.61% and 0.12%, respectively; these in the equivalent condition decreased by 5.31%, 3.95% and 0.33%, respectively, compared with the first year. Under the A1 condition, the annual coefficient of performance (COP) of the system in Beijing thermal load in the 10th year was 62.67% and 38.59% larger than that in Harbin and Shenyang thermal load, respectively.