The Three-dimensional Numerical Borehole Model And Study On Factors Of The Rock-soil Thermal Response Test

With the development of society，the energy crisis and environmental pollutionproblems havebecome more and more serious. And ground source heat pump (GSHP)technology provides a method to solve those problems due to it`s highefficientenergy-saving, environmentally friendly features.During the GSHP systemdesign,accurate geotechnical thermal properties arethe key factors for the design of thesystem. So it is necessary to analysesthegeotechnical heat transfer mechanism andvarious factors that affect rock-soil thermal response test.This paper builds a three-dimensional numerical model considering the influence ofgroundwater flow、backfill materials and other factors with Matlab platform. Thenverifying the reliability of the three-dimensional model by comparing to the classic linesource model.Simulating the performance of ground heat exchanger(GHE) temperaturedistribution in timewith and without groundwater flow.Analyze the temperaturedistribution of surrounding soil and the heat transfer rate of the GHE indifferentgroundwater seepage velocity. Then we vary the groundwater level to see howthe geotechnical thermal properties and heat transfer rate of the GHE change.At last,westudy the influence on calculating the geotechnical thermal properties when the power、flow rate and the length of the test time are different，through the three-dimensionalmodel simulations, to get more accurate results. And this will provides a more effectiveguidance for the design of the GSHP system.