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Tutorial:HeatandMassTransferwiththeMixtureModelandEvaporation-CondensationModelIntroductionThepurposeofthistutorialistodemonstratethesolutionofamultiphaseprobleminvolv-ingheatandmasstransferusingthemixturemultiphasemodelalongwithEvaporation-Condensationmodel.Thistutorialdemonstrateshowtodothefollowing:UsethemixturemodelinANSYSFLUENTtosolveamixturemultiphaseproblem.UseEvaporation-CondensationmodelSolvethecaseusingappropriatesolversettings.Postprocesstheresultingdata.PrerequisitesThistutorialiswrittenwiththeassumptionthatyouhavecompletedTutorial1fromtheANSYSFLUENT13.0TutorialGuide,andthatyouarefamiliarwiththeANSYSFLUENTnavigationpaneandmenustructure.Somestepsinthesetupandsolutionprocedurewillnotbeshownexplicitly.Inthistutorialyouwillusethemixturemultiphasemodel.Thistutorialwillnotcoverthemechanicsofusingthismodel.Instead,itwillfocusontheapplicationofthemodeltosolveamixturemultiphaseprobleminvolvingheatandmasstransfer.FormoreinformationrefertoSection26.4SettingUptheMixtureModelintheANSYSFLUENT13.0User'sGuide.ProblemDescriptionTheproblemtobesolvedinthistutorialisshowninFigure1.Initially,thecontainercontainswater(theprimaryphase)atatemperatureneartheboilingpoint(372K).Thecenterportionofthebottomwallofthecontainerisatatemperatureof573K,whichishigherthantheboilingtemperature.Becauseofconduction,thetemperatureoftheuidnearthiswallwillincreasebeyondthesaturationtemperature(373K).Vaporbubbleswillformandriseduetobuoyancy,establishingapatternsimilartoabubblecolumnwithvaporescapingatthetopandwaterrecirculatinginthecontainer.cANSYS,Inc.March8,20111HeatandMassTransferwiththeMixtureModelFigure1:ProblemSpeci cationPreparation1.Copythemesh le(boil.msh.gz)totheworkingfolder.2.UseFLUENTLaunchertostartthe2DversionofANSYSFLUENT.FormoreinformationaboutFLUENTLauncherseeSection1.1.2StartingANSYSFLU-ENTUsingFLUENTLauncherintheANSYSFLUENT13.0User'sGuide.3.EnableDouble-PrecisionintheOptionslist.Note:TheDisplayOptionsareenabledbydefault.Therefore,afteryoureadinthemesh,itwillbedisplayedintheembeddedgraphicswindow.SetupandSolutionStep1:Mesh1.Readthemesh leboil.msh.gz.File !Read !Mesh...Step2:General1.Checkthemesh.General !Check2cANSYS,Inc.March8,2011HeatandMassTransferwiththeMixtureModelFigure2:MeshDisplayANSYSFLUENTwillperformvariouschecksonthemeshandwillreporttheprogressintheconsole.Ensurethattheminimumvolumereportedisapositivenumber.2.EnablethetransientsolverbyselectingTransientfromtheTimelist.General !TransientStep3:Models1.De nethemultiphasemodel.Models !Multiphase !Edit...cANSYS,Inc.March8,20113HeatandMassTransferwiththeMixtureModel(a)SelectMixturefromtheModellist.(b)EnableImplicitBodyForcefromtheBodyForceFormulationlist.(c)ClickOKtoclosetheMultiphaseModeldialogbox.2.Enableenergyequation.Models !Energy !Edit...AfteryouenabletheEnergyEquationaninformationdialogboxwillopenremindingyoutocon rmthepropertyvaluesthathavechanged.Step4:Materials1.Copywater-liquid(h2olfromthedatabase.(a)ClicktheFLUENTDatabase...toopentheFLUENTDatabaseMaterialsdialogbox.i.Selectwater-liquid(h2ol)fromtheFLUENTFluidMaterialsselectionlist.ii.ClickCopyandclosetheFLUENTDatabaseMaterialsdialogbox.4cANSYS,Inc.March8,2011HeatandMassTransferwiththeMixtureModel(b)Enter1000kg/m3forDensity.(c)Enter0.0009kg/m-sforViscosity.(d)Enter18.0152forMolecularWeight.(e)Enter0forStandardStateEnthalpy.(f)Enter298.15KforReferenceTemperature.(g)ClickChange/CreateandandcloseCreate/EditMaterialsdialogbox.2.Copywater-vapor(h2ofromthedatabase.(a)ClicktheFLUENTDatabase...toopentheFLUENTDatabaseMaterialsdialogbox.i.Selectwater-vapor(h2o)fromtheFLUENTFluidMaterialsselectionlist.ii.ClickCopyandclosetheFLUENTDatabaseMaterialsdialogbox.cANSYS,Inc.March8,20115HeatandMassTransferwiththeMixtureModel(b)Enter0.5542kg/m3forDensity.(c)Enter2014j/kg-KforCp(Speci cHeat).(d)Enter0.0261w/m-KforThermalConductivity.(e)Enter1.34e-05kg/m-sforViscosity.(f)Enter18.0152forMolecularWeight.(g)Enter2.992325e+07forStandardStateEnthalpy.(h)Enter298.15KforReferenceTemperature.(i)ClickChange/CreateandclosetheCreate/EditMaterialsdialogbox.Notethatthestandardstateenthalpiesofvaporandliquidphasearesetsuchthattheirdi erenceequalstolatentheatofvaporization.Theunitofstandardstateenthalpyiskj/kmolandusuallythelatentheatvalueisavaiableinkj/kg.whilespecifyingithere,multiplythatvaluebymolecularwight.Forcorrectspeci cationoflatentheatitisimportanttosetthereferencetemperatureto298.15K6cANSYS,Inc.March8,2011HeatandMassTransferwiththeMixtureModelStep5:Phases1.De netheprimaryphase.Phases !phase-1 !Edit...(a)EnterliquidforName.(b)Selectwater-liquidfromthePhaseMaterialdrop-downlist.(c)ClickOKtoclosethePrimaryPhasedialogbox.2.De nethesecondaryphase.Phases !phase-2 !Edit...(a)EntervaporforName.(b)EnsurethatairisselectedfromthePhaseMaterialdrop-downlist.cANSYS,Inc.March8,20117HeatandMassTransferwiththeMixtureModel(c)Enter0.0002mforDiameter.(d)ClickOKtoclosetheSecondaryPhasedialogbox.3.SelecttheEvaporation-CondensationModelPhases !Interaction...(a)ClicktheMasstab.(b)SelectliquidfromtheFromPhasedrop-downlist.(c)SelectvaporfromtheToPh