高性能地埋管换热器钻孔回填材料的实验研究
Experimental research on high-performance backfill materials for ground heat exchangers
摘要：
通过实验研究了基于水泥、石英砂的回填材料各组分对材料导热系数、稠度、强度及膨胀率等的影响，优选出三种具有良好特性的水泥砂浆回填材料，其导热系数可达2.18～2.34 W/(m·K)。通过对一个工程实例的模拟计算得出，与传统的膨润土回填材料相比，采用这些高性能回填材料能够减少地埋管换热器埋管长度29%～36%，可显著节省地埋管换热器的初投资和降低运行能耗。
关键词：地埋管换热器,水泥砂浆,回填材料,导热系数,埋管长度
Abstract：
Experimentally studies the influences of each component on the thermal conductivity, consistency, strength and expansion ratio of cement-quartz sand grout backfill materials. Recommends three high-performance grout materials with thermal conductivity of 2.18 to 2.34 W/(m·K). A case study shows that application of these cement-sand grout materials can reduce the buried pipe by 29% to 36% in length and the initial investment of ground heat exchangers and running energy consumption significantly compared with conventional bentonite grout.
Keywords:groundheatexchanger,cement-sandgrout,backfillmaterial,thermalconductivity,buriedpipelength