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http://dx.doi.org/10.6110/KJACR.2011.23.2.095

The Effects of the Installation Conditions of Ground Loop Heat Exchanger to the Thermal Conductivity and Borehole Resistance  

Lim, Hyo-Jae (Department of Mechanical Engineering, Hoseo University)
Kong, Hyoung-Jin (Geothermal Energy Education Center, Hoseo University)
Kang, Sung-Jae (Geothermal Energy Education Center, Hoseo University)
Choi, Jae-Ho (R&D Center, Kotec Engineering Co. Ltd.)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.23, no.2, 2011 , pp. 95-102 More about this Journal
Abstract
A ground loop heat exchanger in a ground source heat pump system is an important unit that determines the thermal performance of a system and its initial cost. A proper design requires certain site specific parameters, most importantly the ground effective thermal conductivity, the borehole thermal resistance and the undisturbed ground temperature. This study was performed to investigate the effect of some parameters such as borehole lengths, various grouting materials and U tube configurations on ground effective thermal conductivity and borehole thermal resistance. In this study, thermal response tests were conducted using a testing device to 9 different ground loop heat exchangers. From the experimental results, the length of ground loop heat exchanger affects to the effective thermal conductivity. The results of this experiment shows that higher thermal conductivity of grouting materials leads to the increase effective thermal conductivity from 22 to 32%. Also, mounting spacers have increased by 14%.
Keywords
Ground loop heat exchanger; Ground effective thermal conductivity; Thermal response test; Thermal resistance;
Citations & Related Records
Times Cited By KSCI : 4  (Citation Analysis)
연도 인용수 순위
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