资源描述：
《On a Darcy-Stefan Problem arising in freezing and thawing of saturated porous media.pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、ContinuumMech.Thermodyn.(1999)11:181–191cSpringer-Verlag1999OnaDarcy–StefanProblemarisinginfreezingandthawingofsaturatedporousmediaJoseFranciscoRodrigues´1,JoseMiguelUrbano´21C.M.A.F./UniversidadedeLisboa,Av.Prof.GamaPinto,2–P-1649-003Lisboa,Portugal2C.M.U.C./UniversidadedeCoimbra,Apartado3008–
2、P-3000Coimbra,PortugalReceivedOctober20,1998AmodelwithphasechangeformaterialconvectioninasaturatedporousmediumwithafrozenregionisformulatedasaDarcy-Stefanproblem.WeproposeanewgeneralizedformulationforthisStefan-typeproblemwithconvectiongovernedbyDarcy'slaw.Thisapproach,whichisvalidforirregularg
3、eometrieswithirregularsubregions,hastheadvantageofnotrequiringthesmoothnessofthetemperature,thatrestrictedpreviousmathematicalworkstotwo-dimensionalparticularcases.Weshowexistenceofgeneralizedsolutions,passingtothelimitinsuitableapproximatedproblems,whichinprinciplecanbesolvednumericallybythefin
4、iteelementmethod.1IntroductionInmanyproblemsingeodynamicsandsoilengineeringthewater-icephasechangeplaysanimportantroleonnaturalconvectioninregionsoccupiedbysaturatedporousmedia.Thepresenceandevolutionofthecorrespondinginterface,asshownbyexperimentalobservationsandtheoreticalanalysis,havesignific
5、antinfluenceintheheattransferand,consequently,alsointhefluidmotions.Becauseofthetechnicalimportanceofthisphenomenon,severalmodelshavebeenconsideredforconcreteproblemslikeintheconstructionofpipelinesinpermafrostregions,e.g.GoldsteinandReid[12],liquifiedgasorroadconstructionandmaintenance,e.g.Aguirr
6、e-PuenteandFremond[1],andsoon.Morerecentlythemeltingoficewithnatural´convectioninaporousmediumhasbeenconsideredinparticularcases,e.g.BeckermannandViskanta[4],KazmierczakandPoulikakos[13]orZhangetal.[24].Aninterestingaspectofthenaturalconvectionwithphasechangeinporousmediaistheanalysisofpatterne
7、dgroundformation,e.g.Georgeetal.[11].Applyingalinearinstabilityanalysistoamodelofthisgeophysicalphenomenonformingregularpatterns,McKay[15]hasanalysedtheeffectofvariablethermalparametersonfluidmotionsinthemeltedregion.Althoughphasec
