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http://dx.doi.org/10.7843/kgs.2013.29.2.5

Evaluation of Conventional Prediction Models for Soil Thermal Conductivity to Design Horizontal Ground Heat Exchangers  

Sohn, Byonghu (Green Building Research Division, Korea Institute of Construction Technology)
Wi, Jihae (School of Civil, Environmental and Architectural Engrg., Korea Univ.)
Park, Sangwoo (School of Civil, Environmental and Architectural Engrg., Korea Univ.)
Lim, Jeehee (School of Civil Engrg., Purdue Univ.)
Choi, Hangseok (School of Civil, Environmental and Architectural Engrg., Korea Univ.)
Publication Information
Journal of the Korean Geotechnical Society / v.29, no.2, 2013 , pp. 5-14 More about this Journal
Abstract
Among the various thermal properties, thermal conductivity of soils is one of the most important parameters to design a horizontal ground heat exchanger for ground-coupled heat pump systems. It is well known that the thermal conductivity of soil is strongly influenced by its density and water content because of its particulate structure. This paper evaluates some of the well-known prediction models for the thermal conductivity of particulate media such as soils along with the experimental results. The semi-theoretical models for two-component materials were found inappropriate to estimate the thermal conductivity of dry soils. It comes out that the model developed by Cote and Konrad provides the best overall prediction for unsaturated sands available in the literature. Also, a parametric analysis is conducted to investigate the effect of thermal conductivity, water content and soil type on the horizontal ground heat exchanger design. The results show that a design pipe length for the horizontal ground heat exchanger can be reduced with an increase in soil thermal conductivity. The current research concludes that the dimension of the horizontal ground heat exchanger can be reduced to a certain extent by backfilling materials with a higher thermal conductivity of solid particles.
Keywords
Ground-coupled heat pump system; Horizontal ground heat exchanger; Soil thermal conductivity; Water content; Prediction model;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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