地源热泵地下换热系统的实验研究

地源热泵地下换热系统对于地源热泵系统的稳定运行和地源热泵系统的投入成本起着关键的作用.为了对地下换热系统换热效果和周围土壤的温度场进行实验研究,我们在北京工业大学高科技能源楼建立了一套包含60套不同结构地下换热系统的实验台.利用温度及流量测试装置获得运行过程中温度变化并计算换热量,探求不同结构地下换热系统的换热情况.本实验台还可以收集系统运行过程中地下换热系统的传热温度扩散半径,实验系统不仅为地源热泵的设计提供了数据,而且为地源热泵的深入研究提供了平台.本文给出的部分实验结果证明,根据当地地质情况、负荷需求及系统运行模式配置能源井是至关重要的.

EXPERIMENTAL STUDY OF SUBTERRANEAN HEAT EXCHANGERS IN GROUND SOURCE HEAT PUMP SYSTEM

The heat exchanging performance of the subterranean heat exchangers which are named energy collectors here is the designing foundation of ground source heat pump (GSHP) systems. An experimental system which is including 60 kinds of different energy collectors is built by taking into account many factor. Such as the different buried methods, which includes the single U-shaped pipe, double U-shaped pipe, and triplicate U-shaped pipe subterranean heat exchangers; And the different material that energy collectors be made of including stainless steel, high density polyethylene pipes, and crosslinked polyethylene pipes; And the different backfills in the hole including concrete backfill, sand backfill with bentonite, and slurry. The heat transfer performance of the subterranean heat exchangers is studied for each energy well. This study describes the experiment process on which we have carried in order to obtain comparatively accurate data of the heat exchange capacity, and supply the evaluation and comparison of the different subterranean heat exchangers. The experimental results were obtained from November of 2004 to April of 2005. We believe the water temperature in energy collectors is more important than the heat transfer performance of energy collectors.