地埋管换热器地温监测系统补建实例及测试数据分析
2021-06-15姚木申蔡芸卢宝赵苏民
姚木申 蔡芸 卢宝 赵苏民



摘要 针对天津市某地源热泵项目补建了一套地温监测系统,获得了各监测点温度变化数据,并进行了全年变化规律分析。结果表明,地温监测线在增加保护套管后,其短期变化负荷作用下的温度数值与换热管壁相比存在一个相对固定的偏差,通过必要的数据修正,并不影响地温监测的可靠性。热影响半径与土壤热物性和运行负荷强度密切相关,而本文运行条件下热影响半径在1~1.5 m之间。背景地温监测孔与换热孔群外边界的距离建议大于15 m,以减小孔群换热对数据的干扰。
关 键 词 地源热泵;地温监测;热影响半径;背景地温
中图分类号 TU83 文献标志码 A
Abstract A ground temperature monitoring system is reconstructed for a practical ground source heat pump system in Tianjin. Annual variations of ground te mperatures at different positions and depths are obtained and analyzed. Test results show that after adding protection tubes for monitoring lines, their short-period temperatures under thermal loads obviously deviate from the temperatures at the pipe walls, but such a relatively fixed deviation does not affect the reliability of monitoring ground temperatures after some necessary data modification. Thermal influencing radius (TIR) of ground heat exchangers (GHEs) depends mainly on the ther mal properties of surrounding soils and the intensity of operating loads, and the TIR ranges from 1 to 1.5 m under the present operating conditions. It is recommended that the distance between the monitoring borehole of ground temperature and the outer boundary of heat exchange pipe groups should be greater than 15 m, in order to reduce the possible disturbance by the heat transfer of GHEs.
Key words ground source heat pump; monitoring of ground temperature; thermal influencing radius; background ground temperature
近年来,随着地源热泵技术的迅猛发展,大量地源热泵项目不断投入运行,地源热泵项目呈现规模大、数量多、分布广等特点。但是,实际运行的地源热泵项目是否节能,具体节能效果如何,地埋管换热器周围岩土体温度分布变化究竟怎样?这一系列问题都需要通过实测的运行数据来分析,而运行数据的获取则需要良好的動态监测系统来完成[1]。实际调研表明,由于建设成本、周期或其他方面等原因,许多地源热泵项目初建时并未安装动态监测系统,其中还有一些地温监测传感器及线缆由于长期处于潮湿、腐蚀环境而出现损坏,这给地源热泵项目的运行管理带来很大不便。为解决这些问题,需要对已投用的地源热泵项目进行动态监测系统补建或修复,以保证系统运行管理、节能评价、地质环境影响分析等工作需要。……
