地埋管换热器钻孔长度计算方法研究

摘要

地埋管换热器钻孔长度计算是土壤源热泵系统设计的核心。为规范地埋管换热器钻孔长度计算，从《地源热泵系统工程技术规范》基本要求出发，以合肥市某土壤源热泵工程为例，进行了地埋管换热器钻孔长度计算和校核模拟计算。研究表明，热干扰对地埋管换热器钻孔长度有较大的影响，不考虑热干扰影响的钻孔长度计算结果偏小；由于热堆积的影响，地埋管换热器流体平均出口温度呈现逐年上升趋势。校核模拟计算结果表明地埋管换热器钻孔计算长度能够满足规范的要求。%Sizing the borehole length of ground heat exchangers (GHEs) is the key of designing for the ground source heat pump system. To regulate the method of sizing the borehole length for GHEs from the "Technical code for ground-source heat pump system” requirement, borehole length calculation and checking calculation and simulation are presented through a case study of a ground source heat pump project in Hefei. Results indicate that the thermal interference has a great influence on the borehole length of GHEs. Without considering the thermal interference the borehole length will be smaller. Due to the effect of the heat accumulation underground, the average fluid outlet temperature of ground heat exchanger will increase gradually year by year. Simulation verification results show that the borehole length of GHE can meet the requirement of the technical code.