Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Evaluation of Effective Thermal Conductivity and Thermal Resistance in Ground Heat Exchanger Boreholes

지중 열교환기 보어홀에서의 유효 열전도도 및 열저항 산정

  • Sohn Byong Hu (Fire & Engineering Services Research Department, KICT) ;
  • Shin Hyun-Joon (Fire & Engineering Services Research Department, KICT) ;
  • Park Seong-Koo (Fire & Engineering Services Research Department, KICT)
  • 손병후 (한국건설기술연구원 화재 및 설비 연구부, (주)지오테크) ;
  • 신현준 (한국건설기술연구원 화재 및 설비 연구부, (주)지오테크) ;
  • 박성구 (한국건설기술연구원 화재 및 설비 연구부, (주)지오테크)
  • Published : 2005.08.01
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Abstract

The objective of this study is to determine the effective thermal conductivity and thermal resistance values in test boreholes with three different fill materials. To evaluate these heat transfer properties, in-situ tests on four vertical boreholes were conducted by adding a monitored amount of heat to water over various test lengths. Two parameter estimation models, line-source and numerical one-dimensional models, for evaluation of thermal response test data were compared when applied on the same four data sets. Results show that the average thermal conductivity deviation between measured data and these two models is in the range of $3.03\%$ to $4.45\%$. The effect of increasing grout thermal conductivity from 1.34 to 1.82 $W/m^{\circ}C$ resulted in overall increases in effective formation thermal conductivity by $11.1\%$ to $51.9\%$ and reductions in borehole thermal resistance by $11.6\%$ to $26.1\%$.

Keywords

References

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