Research of undergroundwater temperature recovery characteristics on site after water-source heat pump heating — In Shenyang City as an example

To study the underground water temperature restoration characteristics after the water-source heat pump engineering´s heating, the underground water temperature restoration range and rate at the different depths and time of pump and rejection wells of 13 heat pump engineering areas of Shenyang urban area were monitored and analyzed. Results show that the shallow groundwater´s temperature is affected by factors such as the climate and supplies of Hunhe River; below the ground surface, from 0 to 25m is the alternating temperature zone; from 25 to 35m is the constant temperature zone for its stable temperature. The temperature of the pump wells and rejection ones can gradually recovery to consistent after 20-60 days, the recovery ability increases with its depth raising. Additionally, under the force of the hydrodynamic field, the groundwater exchanges heat with the aquifer in the process of runoff, and in the runoff direction the underground water temperature changes regularly. In the practical water-source heat pump engineering, groundwater temperature recovery characteristics should be comprehensively mastered, and only by grasping the trend of the groundwater temperature field of the regional aquifer accurately can the heat pump efficiency be improved effectively.