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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Evaluation of Ground Temperature and Soil Thermal Diffusivity Using the Soil Temperature Data of KMA

기상청 지중 온도 데이터를 이용한 지중 온도 및 토양 열확산계수 산정

  • Sohn, Byong-Hu (Plant Research Division, Korea Institute of Construction Technology)
  • 손병후 (한국건설기술연구원 설비프랜트연구실)
  • Received : 2011.05.09
  • Accepted : 2011.05.27
  • Published : 2011.06.01
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Abstract

Storing and transferring heat in soils is governed by the soil thermal properties and these properties are therefore needed in many engineering applications, including horizontal ground heat exchanger for ground-coupled heat pumps. This paper presents the evaluation results of the ground subsurface temperature and apparent thermal diffusivity of soils by using ground temperature data collected at the depths of 0.5 m, 1.0 m, 1.5 m, 3.0 m, and 5.0 m at four sites. The existing correlation assuming that the soil was homogeneous and of constant thermal diffusivity was applied to calculate the subsurface temperature and two analytical equations, amplitude and phase equation, were also used to evaluate the soil apparent thermal diffusivity. Comparison of the estimated and of the measured values of the subsurface temperature has shown that the empirical correlation predicts quite accurately the ground temperature at various depths. Based on the one-dimensional heat conduction equation, the apparent thermal diffusivity can be estimated by the two equations.

Keywords

References

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