The Experimental Research On Ground Heat Exchanger Buried In Beach

For utilizing the renewable ground thermal energy, the ground source heat pump (GSHP) system has the features of protecting the environment and reducing electric power consumption. As we know, the heat transfer of heat exchanger (GHE) is affected by a lot of factors, where groundwater advection has a great impact indicated by experimental data. While almost all the design tools for GHE are based on principles of heat conduction. However, pipe lies in zones along the coast where have plentiful groundwater will be affected by groundwater advection greatly. In that case, there happens transient, complicated coupled heat conduction and groundwater heat advection in the saturated soil. It will cause the GHE size much bigger, and make the short-time economics of GSHP, if GSHP design methods based on models only consider the heat conduction.Viewed of the above, the theoretical and experimental researches on the performance of GHE lay in zones along the coast are implemented in this paper. Based on theoretical analysis, the numerical model of GHE under coupled heat conduction and advection is built and calculated by CFD. Based on the Darcy experiment model, an experimental facility is built including linear electrical heater as underground pipe, water pouring out or pouring into the sandbox modeling the tide. Through the experiment, the numerical model of coupled heat conduction and advection and its implementation about GHE is validated in one hand; in the other hand, the influences of such factors as ground water advection, the way of running, flow rate, design load on heat transfer of GHE and the surrounding soil are analyzed. Thus all of those can present basic data for application of GSHP. The result shows that tidal effects are advantage to the ground-soil temperature restoration around the underground heat exchanger, as well as improving performance of the ground source heat pump system.