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Heating unsaturated medium sand / J. Ewen in Géotechnique, Vol. 39 N°3 (Septembre 1989) 

Public ISBD [article]  in Géotechnique > Vol. 39 N°3 (Septembre 1989) . - pp. 455 –470 Titre : Heating unsaturated medium sand Type de document : texte imprimé Auteurs : J. Ewen, Auteur ; H. R. Thomas, Auteur Année de publication : 2007 Article en page(s) : pp. 455 –470 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Partial  saturation  Temperature  Computation  Sands  Soil  properties Résumé : A theoretical, experimental and numerical investigation of combined heat and mass transfer in unsaturated sand is described. The theoretical formulation adopted is that of Philip & de Vries but slightly different forms of the vapour transfer dif-fusivities are developed. Experimental work is reported on the determination, for a medium sand, of the full set of material parameters incorporated in the formulation, using both methods developed by the Authors and standard techniques. Explicit equations are given for the capillary potential, unsaturated hydraulic conductivity and thermal conductivity as functions of moisture content and temperature. Laboratory experimental results are presented for the steady temperature distribution within an unsaturated sample of the sand in which a rod is buried and heated. The pattern of moisture content values achieved reveals a two region response, a dry zone surrounding the rod and wet sand elsewhere. The development of a numerical simulation of the heating experiment using a finite difference solution algorithm is described. A self implicit scheme, driven to steady state through a false transient, was employed. Good agreement was found between temperatures in the simulation and the experiment. The work described is unusual in that equal emphasis has been placed on experimentation, especially the determination of the soil's physical properties, and numerical modelling and the two-dimensional coupled partial differential equations describing combined heat and mass transfer have been solved without simplification. ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/search?value1=%27soil+properties%27&option1=ful [...] [article] Heating unsaturated medium sand [texte imprimé] / J. Ewen, Auteur ; H. R. Thomas, Auteur . - 2007 . - pp. 455 –470. Génie Civil Langues : Anglais (eng) in Géotechnique > Vol. 39 N°3 (Septembre 1989) . - pp. 455 –470 Mots-clés : Partial  saturation  Temperature  Computation  Sands  Soil  properties Résumé : A theoretical, experimental and numerical investigation of combined heat and mass transfer in unsaturated sand is described. The theoretical formulation adopted is that of Philip & de Vries but slightly different forms of the vapour transfer dif-fusivities are developed. Experimental work is reported on the determination, for a medium sand, of the full set of material parameters incorporated in the formulation, using both methods developed by the Authors and standard techniques. Explicit equations are given for the capillary potential, unsaturated hydraulic conductivity and thermal conductivity as functions of moisture content and temperature. Laboratory experimental results are presented for the steady temperature distribution within an unsaturated sample of the sand in which a rod is buried and heated. The pattern of moisture content values achieved reveals a two region response, a dry zone surrounding the rod and wet sand elsewhere. The development of a numerical simulation of the heating experiment using a finite difference solution algorithm is described. A self implicit scheme, driven to steady state through a false transient, was employed. Good agreement was found between temperatures in the simulation and the experiment. The work described is unusual in that equal emphasis has been placed on experimentation, especially the determination of the soil's physical properties, and numerical modelling and the two-dimensional coupled partial differential equations describing combined heat and mass transfer have been solved without simplification. ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/search?value1=%27soil+properties%27&option1=ful [...]