| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure of an underground heat exchanger and its corrosion preventing method, having a wide heat transfer area and high heat exchanging efficiency to be applied to buildings such as a detached house, a multiple dwelling house and a building. SOLUTION: In this underground heat exchanger having the structure wherein an inner tube opened at both ends is freely fitted to an outer tube sealed at its tip and opened at the other end, both tubes are buried in the ground in a state that the tip of the outer tube is directed downward, and the air is allowed to flow in a clearance between the inner tube and the outer tube to exchange heat with the geothermal heat, a plurality of recessed grooves having the cross-sectional shape expanding to the bottom, are formed in the longitudinal direction of the outer tube, and projecting portions of a metallic blade having the projecting portions laterally expanding at their tips, are fitted to the recessed grooves. The fitting is performed by shrinkage fitting or freeze fitting. The outer tube is divided into three in the longitudinal direction, a flange is disposed on each divided pipe, and each divided pipe is detachably joined at the flange portion. COPYRIGHT: (C)2007,JPO&INPIT |
