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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Thermal Conductivity Measurement of Grouting Materials for Ground Heat Exchanger Borehole

지중 열교환기 보어홀 그라우팅 재료의 열전도도 측정

  • 손병후 (한국건설기술연구원 화재.설비연구부) ;
  • 신현준 (한국건설기술연구원 화재.설비연구부)
  • Published : 2006.06.01
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Abstract

This paper concerns the measurement of thermal conductivity of grouting materials for ground loop heat exchanger. A thermal conductivity meter, QTM-500 based on modified transient hot wire method was used to measure the thermal conductivity of neat bentonite and mixtures of bentonite and various additives. Relative to the total mixture mass, as the percent additive was increased the mixture thermal conductivity increased. For the bentonite-silica sand mixtures, the higher density of the sand particles resulted in much higher mixture thermal conductivity. The quartzite and silica sands produced the largest increases in mixture thermal conductivity, while common masonry and limestone sands produced lower thermal conductivity increases.

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References

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