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http://dx.doi.org/10.12652/Ksce.2012.32.2C.069

Estimation of Thermal Conductivity of Weathered Granite Soils  

Park, Hyunku (카이스트 건설 및 환경공학과)
Park, Hansol (삼성물산)
Lee, Seung-Rae (카이스트 건설 및 환경공학과)
Go, Gyu-Hyun (카이스트 건설 및 환경공학과)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.32, no.2C, 2012 , pp. 69-77 More about this Journal
Abstract
In general, geothermal energy pile and horizontal ground heat exchangers are installed in shallower depths than conventional vertical ground coupled heat pumps. Consequently their heat exchange performance is strongly governed by thermal conductivity of soil layer. Previous studies have shown that the thermal conductivity of soil above ground water table significantly affects the heat exchange rate because of partially saturated condition in soil and consequent variation of soil thermal conductivity. This paper presents a study result on the prediction of thermal conductivity of weathered granite soils. For weathered granite soils sampled from 5 locations, thermal conductivity tests were conducted with varying porosity and degree of saturation. The existing thermal conductivity models in literatures appeared inappropriate to the weathered granite soils. Hence, an empirical equation was proposed in this paper and its validity was examined by applying it to thermal conductivity test results obtained for weathered granite soils in this study and from literatures.
Keywords
soil thermal conductivity; Korean weathered granite soil; Kersten's number; empirical equation; degree of saturation;
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Times Cited By KSCI : 3  (Citation Analysis)
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