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

지중열교환기 설치 조건이 지중 유효 열전도도와 보어홀 열저항에 미치는 영향

  • 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.)
  • 임효재 (호서대학교 기계공학과) ;
  • 공형진 (호서대학교 지열인력양성센터) ;
  • 강성재 (호서대학교 지열인력양성센터) ;
  • 최재호 (코텍엔지니어링)
  • Received : 2010.05.31
  • Accepted : 2010.10.12
  • Published : 2011.02.10

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

Acknowledgement

Supported by : 호서대학교

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Cited by

  1. An Experimental Study on the Cooling and Heating Performance of a Residential Ground Source Heat Pump System vol.25, pp.3, 2013, https://doi.org/10.6110/KJACR.2013.25.3.156