岩土热响应试验在土壤源热泵系统设计中的应用

Application of Geo-thermal Response Test in the Design of Ground-source Heat Pump System

结合南京某土壤源热泵项目,分析了岩土热响应试验中的关键问题,对岩土热响应测试的方法与步骤进行了规范的阐述。针对某一实际项目建立了100m深双U型垂直埋管试验井测试装置进行热响应试验,并采集了岩土热物性参数,得到了土壤原始地温以及地埋管系统的供回水温度响应曲线,进而确定了每延米井深的换热量等参数。数据分析表明,土壤的原始地温为17.95℃,夏季工况(35℃)和冬季工况(5℃),每延米井深的换热量分别为69.6W/m和51.2W/m。该工程区域内综合地质条件比较适宜采用土壤源热泵空调系统。

Combining with a ground source heat pump project in Nanjing, the key issues of Geo-thermal response test are analyzed and the normative test methods and steps are summarized. Vertical double U-tube test wells are taken as testing apparatus, and local soil thermal parameters are collected through field test of two test wells with depth of 100m. Furthermore, the original ground temperature and the inlet and outlet water temperature response curve of the underground heat exchanger are also obtained, which are used to determine the heat exchange quantity of per well depth and other parameters. It is concluded from data analysis： the original ground temperature is 17.95℃; the heat exchange quantity of per well depth is 69.6W/m under summer conditions （35℃） and 51.2W/m under winter conditions （5 ℃）. All of those conclusions prove that comprehensive geological conditions of the project area are suitable for the use of ground source heat pump air conditioning system.