地源热泵夏季运行地温场变化特性试验研究

Experimental Study on Ground Temperature Change Characteristics of Groundsource Heatpump System Running in Summer

摘要:

以同济大学某实验室地埋管地源热泵工程为例，通过对地埋管换热区地温场及地源热泵系统运行参数进行监测，分析研究了地源热泵系统夏季运行地温场的变化特性以及地温场变化对地源热泵系统运行效率的影响.结果表明：夏季累计运行44 d，土壤平均升温幅度为0.64 ℃；不同深度测点温度变化幅度随深度增加逐渐减小，120 m深度地温几乎无变化；换热区土壤地温恢复速率为0.14 ℃?100 d-1；随着换热区土壤温度的升高，地源侧进出水温差降低幅度为0.87 ℃，机组性能系数亦随之降低，系统换热效率下降.

Abstract:

Ground temperature and systematic parameters of running groundsource heatpump system were collected from a laboratory in Tongji University, and the change laws of the parameters were analyzed to evaluate its effect on the system. The following conclusion can be drawn: the ground temperature rises 0.64 ℃ in 44 d, the range of temperature variation decreases with depths, and the temperature will be a relative constant when depth is deeper than 120 m. The ground temperature recovery rate is 0.14 ℃?100 d-1, and with the increasing of soil temperature, the temperature gap of inlet and outlet water will decrease 0.87 ℃ and the system performance rate and heat transfer efficiency will decline.