地源热泵地埋管换热器传热特性影响因素分析

Analysis of Influence Factors on Heat Transfer Characteristics of Ground Heat Exchanger for GSHP

以地源热泵地埋管换热器为研究对象,介绍了U型管地下换热器的换热过程,并在该种换热器简化图的基础上,对影响该换热器传热特性的因素分别进行了分析,尤其对影响因素中的介质流量、埋管深度、土壤材料、回填材料、地下水水位、U型管间距等进行了重点分析。同时,分别对砂石地质及黏土地质条件下单U、双U型地埋管换热器的经济性作了分析。在埋管方式相同的情况下,在黏土地质条件下的经济成本要低于在砂石地质条件下的经济成本,这主要是由于在黏土地质条件下的钻井费用要远远低于在砂石地质条件下的钻井费用。通过此次分析,对未来地源热泵系统地埋管换热器的应用及改进具有一定的指导意义。

It focuses on the ground heat exchangers and explains the heat transfer process in the U-tube ground heat exchangers. Based on the simplified structural drawing of this ground heat exchanger, the factors which will influence the heat transfer characteristics were analyzed, especially the medium flow rate, pipe laying depth, soil material, backfill material, underground water level, U-tube pitch, etc. Meanwhile, it respectively analyzes the economical efficiency of using single U-tube and double U-tube ground heat exchangers in the geological conditions of dinas and clay. Because of the much lower cost in drilling, the economical cost in clay geological condition is lower than that in dinas geological condition when they are in the same pipe laying. By doing this analysis, a guidance can be given to the applications and further improvements of ground heat exchangers in ground source heat pump in the future.