KIEAE Journal

Korea Institute of Ecological Architecture and Environment (한국생태환경건축학회)
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A study on the Heat Transfer Performance according to Ground Heat Exchanger Types

지중열교환기의 종류에 따른 열전달 성능에 관한 연구

  • 황석호 (연세대학교 친환경건축연구센터) ;
  • 송두삼 (성균관대학교 건축공학과)
  • Received : 2010.07.13
  • Accepted : 2010.08.06
  • Published : 2010.08.30
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Abstract

Generally, ground-source heat pump (GSHP) systems have a higher performance than conventional air-source systems. However, the major fault of GSHP systems is their expensive boring costs. Therefore, it is important issue that to reduce initial cost and ensure stability of system through accurate prediction of the heat extraction and injection rates of the ground heat exchanger. Conventional analysis methods employed by line source theory are used to predict heat transfer rate between ground heat exchanger and soil. Shape of ground heat exchanger was simplified by equivalent diameter model, but these methods do not accurately reflect the heat transfer characteristics according to the heat exchanger geometry. In this study, a numerical model that combines a user subroutine module that calculates circulation water conditions in the ground heat exchanger and FEFLOW program which can simulate heat/moisture transfer in the soil, is developed. Heat transfer performance was evaluated for 3 different types ground heat exchanger(U-tube, Double U-tube, Coaxial).

Keywords

References

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