| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an underground heat use system reducing retention of heat within an underground heat exchange well and having excellent heat exchange efficiency. <P>SOLUTION: To construct the underground heat exchange well 1 in a bore hole method, excavation penetrating through a first aquifer and reaching a second aquifer is performed. Within the underground heat exchange well 1, an underground heat exchanger 2 such as a U-tube is installed. An air gap deeper than the first aquifer is filled with pea gravel 3 having a grain size of 4-6 mm, and a section shallower than the first aquifer in which flowing of underground water is not expected is filled with silica sand 4 having the grain size of 2-4 mm. The section filled with the pea gravel 3 is a portion serving as an underground water flowing part 5 to promote flow of underground water, and in accordance with conditions, for example, a flow of underground water from the second aquifer to the first aquifer is generated. Since a vertical flow of underground water in the underground water flowing part 5 is added to a flow of underground water within the first aquifer and the second aquifer, heat retention in the vicinity of the underground heat exchange well 1 can be drastically reduced, to improve heat exchange efficiency. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
