西安中深层U型对接换热井取热能力及热影响半径OA北大核心CSTPCD

Deep-borehole heat exchangers(DBHE)is currently recognized as the most environmentally friendly way to exploit geothermal energy.The deep U-shaped borehole heat exchanger is a new type of DBHE which is being explored.Heat extraction capacity and influence radius are the important problems in the process of popularizing this technology.Based on the measured parameters of ground temperature and thermophysical properties,the heat extraction capacity and influence radius of the 2 500 m deep U-shaped borehole heat exchanger are analyzed by the way of in-situ test and numerical simulation in Caotan area of Xi'an.The results show that the sustainable heat extraction power of the heat exchanger in 30 years is closed to 750 kW,with an average linear meter of 144 W;The attenuation degree and range of wall rock temperature increase with the increase of heat extraction power;The influence radius of the deep U-shaped borehole heat exchanger are different at different depths,and the deep stratum is larger than the shallow stratum as a whole;The influence radius of the 2 500 m deep U-shaped borehole heat exchanger with the heat extraction rates of 750 kW can greater than 100 m after work for 30 years,and there is a certain degree of thermal interference between the inlet well and outlet well of the Deep U-shaped borehole exchanger.