Thermal Conductivity of Compost Biocover Subjected to Freeze-Thaw Cycles

F. Moghbel, M. Fall

In the proceedings of: GeoManitoba 2012: 65th Canadian Geotechnical Conference

Session: M3C - GeoEnvironmental II

ABSTRACT: In this article, the key heat transfer parameter, thermal conductivity, of a biocover made of compost in wide range of water contents, freeze-thaw cycles (FTC) is investigated by means of transient method. The samples are kept at -12C for freezing and at room temperature (23C) for thawing. The results obtained have shown that the FTCs have impact on thermal conductivity of compost biocover. However, approximately more than 70% of total thermal conductivity changes occur in the first three FTCs. Moreover from the results, it has been found that the linear relation between thermal conductivity and degree of saturation is valid even under FT condition. Furthermore, it is found that the previously available thermal conductivity models (e.g. Kersten, 1949; Johansen, 1975 and Cote and Konrad, 2005) cannot adequately capture the effect of FTC on the thermal conductivity of compost biocover. Therefore, using the experimental data of the current study, a modified model isproposed.

RÉSUMÉ: Dans cet article, le paramètre clé de transfert de chaleur, la conductivité thermique, d'un biorecouvrementcomposéde compost soumis à une large gamme de teneur en eau et de cycles de gel-dégel (CGDtransitoire. Les échantillons sont conservés à -12C pour la congélation et à la température ambiante (23C) pour la décongélation. Les résultats ont confirmé que les CGDs influencent la conductivité thermique du biorecouvrement. Cependant, environ 70% des changements de la conductivité thermique se produisent dans les trois premiers CGDs. En outre, même dans des conditions GDs, la relation linéaire entre la conductivité thermique et le degré de saturation est prédiction de la conductivité thermique (par exemple Kersten, 1949; Johansen, 1975 et Côté et Konrad, 2005) ne peuvent pas considérer suffisamment l'effet de la CGD sur la conductivité thermique du biorecouvrement compost. Par conséquent, en utilisant les résultats expérimentaux de l'étude actuelle, un modèle modifié est proposé.

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Cite this article:
F. Moghbel; M. Fall (2012) Thermal Conductivity of Compost Biocover Subjected to Freeze-Thaw Cycles in GEO2012. Ottawa, Ontario: Canadian Geotechnical Society.

@article{Paper381,author = F. Moghbel; M. Fall,title = Thermal Conductivity of Compost Biocover Subjected to Freeze-Thaw Cycles,year = 2012}