Ｓｌｉｎｋｙ‐ｃｏｉｌ式水平型地中熱交換器のフィールド試験

概要

論文の詳細を見る
For the evaluation of the heat exchange capacity of horizontal Ground Heat Exchangers (GHEs), field tests were carried out in a Geothermal Heat Pump (GeoHP) system in Fukuoka City, Japan. Slinky-coils were employed as the type of horizontal GHEs considering the limited land space for installing GHEs in most of the GeoHP systems in Japan. Two types of installations of Slinky-coils were examined, namely, horizontal and vertical settings in trenches of 1.5 m deep excavated in the shallow ground. In the cases of horizontal settings, three types of pitches of loops, 0.4 m, 0.6 m and 0.8 m, were tested to investigate the influences of loop pitches on heat exchange performances. The GHEs were connected to a heat pump and a circulation pump to be completed as a GeoHP system. Using the GHEs, thermal response tests and long-term air-conditioning tests were carried out from 2008 to 2010 for collecting detailed operation data and ground temperature data. The obtained field data were interpreted to evaluate the heat exchange capacity of the horizontal GHEs and to compare the heat exchange performances with those of vertical GHEs.The field tests showed that horizontal installation of Slinky-coils results in superior performance to vertical installation in terms of energy efficiency, due to the larger distance to the land surface. Also, the strong influence of the loop pitches on heat exchange capacities was clarified in all tests. Finally, the heat medium temperatures measured in the air-conditioning test showed that horizontally-installed Slinky-coils with 0.4 m pitch have comparable heat exchange capacity to a vertical U-tube GHE drilled in a formation of high thermal conductivity (=2.76 W/(mK)). This suggests that Slinky-coil GHE could be a cost-effective type of GHE considering its low installation costs.
日本地熱学会の論文

Ｓｌｉｎｋｙ‐ｃｏｉｌ式水平型地中熱交換器のフィールド試験

スポンサーリンク

概要

日本地熱学会 | 論文

スポンサーリンク