热响应测试在土壤热交换器设计中的应用

分析了土壤热交换器系统的影响因素以及设计与施工中存在的问题,介绍了自主研制的移动式地源热响应测试装置原理与构成。针对天津市某地源热泵项目,阐述了热响应测试的方法与步骤,得到了项目所在地的无干扰地温以及地埋管系统的供回水温度响应曲线。利用线源理论,得到了地埋管换热器钻孔的导热系数及热阻,分析了测试装置与环境的热损失和热增益、测试时间、供电稳定性、无干扰地温、不同深度土壤热导率的变化以及地下水流动对热响应测试造成的影响。测试结论对于指导土壤热交换器设计与施工具有一定的参考价值。

APPLICATION OF GEO-THERMAL RESPONSE TEST IN THE DESIGN OF GROUND HEAT EXCHANGER

The influence factors of ground heat exchanger system and existed questions in design and construction of ground source heat pump engineering were analyzed,and the principle and structure of self-developed movable geo-thermal response test apparatus were introduced.Take a real engineering as example,the method and step of geo-thermal response test were illustrated,the in-situ undisturbed far-field ground temperature and inlet and outlet temperature response curve of ground heat exchanger were obtained.Through the line-source theory,the borehole thermal conductivity and thermal resistance were obtained.The effect of different factors to geo-thermal response test was put forword,such as heat damage and plus between test apparatus and environment,test durance time,power supply stability,undisturbed ground temperature,variety of ground thermal conductivity along the length of borehole and ground water flow.Test results possess the certain reference value for the design and construction of ground heat exchanger.