Journal of the Korean Society for Geothermal and Hydrothermal Energy (한국지열·수열에너지학회논문집)

Korean Society for Geothermal and Hydrothermal Energy (한국지열·수열에너지학회)
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Effect of Soil Thermal Conductivity and Moisture Content on Design Length of Horizontal Ground Heat Exchanger

토양 열전도도와 수분함량이 수평형 지중열교환기 설계 길이에 미치는 영향

  • Sohn, Byong-Hu (Green Building Research Division, Korea Institute if Construction Technology)
  • 손병후 (한국건설기술연구원 그린빌딩연구실)
  • Received : 2012.01.13
  • Accepted : 2012.02.03
  • Published : 2012.03.01
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Abstract

This paper reviewed and evaluated some of the commonly used prediction models for thermal conductivity of soils with the experimental data. Semi-theoretical models for two-component materials were found inappropriate to estimate the thermal conductivity of dry state soils. It came out that the model developed by Cote and Konrad gave the best overall prediction results for unsaturated soils available in the literature. However, it still needs to be improved to cover a wider range of soil types and degrees of saturation. In the present study, parametric analysis is also conducted to investigate the effect of soil type and moisture content on the horizontal ground heat exchanger design. The analysis shows that horizontal ground heat exchanger pipe length is reduced with the increase of soil thermal conductivity and water content. The calculation results also show that horizontal ground heat exchanger size can be reduced to a certain extent by using backfilling material with a higher thermal conductivity of solid particles.

Keywords

References

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