Abstract Summary
Energy tunnel is a new type of geothermal exchanger in ground source heat pump systems due to their technical and cost improvements over traditional borehole geothermal exchangers. An in situ full scale study using the thermal response and thermal performance tests (TRT and TPT) is performed to investigate the factors affecting the heat exchange capacity in Badaling Energy Tunnel of Beijing Zhangjiakou High speed Railway. This paper analyzes the influences of constant heating power, inlet water temperature, air temperature in tunnel, circulating water flow velocity, operation mode, and pipe connection on the heat exchange capacity of the energy tunnel.
