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1、VOL.9,NO.5WATERRESOURCESRESEARCHOCTOBER1973AnalysisofCoupledHeat-FluidTransportinPartiallyFrozenSoilR.L.HARLANWaterResourcesBranch,Departmento]theEnvironment,Ottawa,Ontario,CanadaAnanalogycanbemadebetweenthemechanismsofwatertransportinpartiallyfrozensoilsandthose
2、inunsaturatedsoils.ByuseofthisanalogyaDarcianapproachisappliedtotheanalysisofcoupledheat-fluidtransportinporousmediawithfreezingandthawing.Withtheaidofanumericalmodel,freezing-affectedsoil-waterredistributionandinfiltrationtofrozensoilareexaminedfromaphenomenolog
3、ical.pointofview,andtheeffectsofsoiltypeandinitialconditionsontheresponseofahypotheticalsoilcolumnarestudied.Ingeneral,themodelshowsthattherateofupwardredistributionofsoilwatertoafreezingzoneatthesoilsurfacedecreasesfromcoarse-texturedsoilstofine-texturedsoilsand
4、decreaseswithin-creaseindepthtothewatertable.Subsequentredistributionduringmeltingofthefrostwedgeisshowntooccurataratelessthanthatassociatedwithfreezing.Infiltrationtopar-tiallyfrozensoilisalsoshowntohaveasignificantinfluenceonsoil-waterredistributionandtherespon
5、seofthegroundwatertable.Conceptually,waterinsoilsatmoisturecon-pendmainlyontemperature[AndersonandtentslessthansaturationcanbevisualizedHoekstra,1965b]andexceptforverydrysoilsasoccupyingwedge-shapedvolumesintercon-tobenearlyindependentoftotalwatercon-nectedbythin
6、liquidfilmsexistingbetweentent,thatis,liquidwaterplusice[Lowetal.,clayplateletsandonparticlesurfaces[Kemper,1968a;Williams,1968].Thethicknessofthe1960].Liquidtransferbetweenwedge-shapedliquidfilmsdecreasesfrom50Aormoreatvolumesandthereforethroughsoilingeneral0?Ct
7、oabout9Aat--5?C;from--5?Ctomusttakeplacethroughthesefilms.Becauseliquidnitrogentemperatures,filmthicknessde-thepropertiesoftheseadsorbedfilmsdonotcreasesfromabout9Ato3A[Anderson,changesignificantlywithtemperaturesabove1968].0?C,liquidtransferunderathermalgradient
8、Whensoilandwaterataconstantvaporisassumedtobeinsignificantformostfieldpressureandtemperatureareinequilibrium,andlaboratorysituations.Thevalidityofthistheresult