CEL-L03-VolumeFractionTool

Abaqus/CAEVolumeFractionToolLecture3L3.2CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitOverview•Introduction•Usingthevolumefractiontool•TipsIntroductionL3.4CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitIntroduction•ItisnotrequiredthattheEulerianmeshconformtoinitialmaterialboundaries.•Elementsmaybepartiallyfilledwithmaterial.•OftenasimplerectangulargridEulerianmeshisused.•Theregular-shapedelementsaremoreaccurateandlesscomputationallyexpensivethandistortedelements.•Material-filledEulerianelementsinfluencetheAbaqus/Explicitstabletimeincrementsize(Δt)inthesamewayLagrangianelementsdo.whereLeistheelementcharacteristiclengthandcdisthedilatationalwavespeed(i.e.,speedofsoundinthematerial)edLtcL3.5CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitIntroduction•TheAbaqus/CAEvolumefractiontoolcancalculatehowmuchmaterialeachEulerianelementcontains.MeshedEulerianpartinstanceReferencepartinstancerepresentinginitialmaterialdomainvolumefractiontoolAdiscretefieldusedtoassignmaterialtotheEulerianpartinstanceL3.6CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitIntroduction•Thereferencepartinstancemayrepresentamaterial-filledregionoranemptyregion(i.e.,onefilledwithvoid).Materialinstance(e.g.,adropletoffluid)DiscretefieldDiscretefieldMaterialinstance(e.g.,fluidsurroundingaroundobject)UsingthevolumefractiontoolL3.8CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool•Example:WashingmachinewithhigherwaterlevelOriginalwaterlevelInitialwaterlocationdefinedwithsomesimplepartitionsintheEuleriangeometry.Newwaterlevel•Twotubbafflesandballinitiallyimmersedinwater.•UsevolumefractiontooltodefineinitialwaterlocationthatdoesnotoverlaptheLagrangianbodies.L3.9CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool•Eulerianpartmustbemeshedbeforeyoucanapplythevolumefractiontool.•Theresultingdiscretefieldwillcontainelementvolumefractionsthatareuniquetothismesh•IfyouremeshtheEulerianpart,youwillneedtoreapplythevolumefractiontool.1.CreateandmeshtheEulerianpartL3.10CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool•Theparttypecanbe:•deformable,•Eulerian,•ordiscreterigid.•Itmustbe:•athree-dimensionalsolid•orafully-enclosedthree-dimensionalshell.•Thereferencepartinstancecanbe:•unmeshedgeometry,•meshedgeometry,•Inthiscasethemeshwillbeusedinthevolumefractioncalculation,evenifthepartisonlypartiallymeshed.•oranorphanmeshpart;2.CreateareferencepartrepresentinginitialmaterialgeometryAquarterofthereferenceparthasbeenremovedfromthedisplaysotheholeintheinteriorisclearlyvisible.Entirereferencepart(translucent)L3.11CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool3.InstancethepartsandpositionthereferencepartwithintheEulerianpartAgain,aquarterofthereferencepartinstancehasbeenremovedfordisplaypurposesonly.L3.12CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool•TheresultingdiscretefieldcontainstheelementvolumefractionsrequiredtodefinetheinitialpositionofthewaterinthecurrentEulerianmesh.•Ifyouremeshthepartyoumustrecreatethediscretefield.4.UsethevolumefractiontoolL3.13CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool5.AssignmaterialtoEulerianpartDouble-clicktoselecttheEulerianregion(theentirepartinstanceinthisexample)ChoosethediscretefieldcreatedbythevolumefractiontoolL3.14CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitUsingthevolumefractiontool•Inthisexample,thereferencepartinstance’sonlypurposeistoidentifytheinitiallocationofthewaterwithintheEuleriandomain.•Ifthereferenceinstanceisnotmeshed,Abaqus/CAEwillomititfromtheanalysisautomatically;•hence,suppressingthereferenceinstanceisoptionalinthisexample.•Suppressionisrecommended,however,toavoidunintentionaluseofthereferencegeometrywhendefiningloads,boundaryconditions,etc.6.Suppressthereferencepartinstance(optional)AssemblywithreferencepartinstanceAssemblywithreferencepartinstancesuppressedTipsL3.16CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitTips•IfyouremeshtheEulerianpart,youmustreapplythevolumefractiontool.•Thediscretefieldcreatedbythevolumefractiontoolismeshdependent.•Whenyouassignmaterialsusingdiscretefields,thecorrespondinginput(.inp)filecontainsalineperelementperfield.•IftheEulerianmeshisfinetheinputfilesizewillbelarge.•Whereapplicable,partitiontheEuleriandomaingeometryanduseelement-basedsetstodefinetheinitialvolumefraction.L3.17CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitTips•ForafineEulerianmeshvolumefractioncalculationscanbeslow.•Forsuchcases,considerusingthelowaccuracysetting.•Aloweraccuracyresultsinfasterperformanceforthetool.•Thevolumefractiontoolcancreateasetcontainingallnodesconnectedtoelementswithnonzerovolumefractionsinthediscretefield.•Thissetissometimesusefulfor:•Verifyingthatnonzerovolumefractionsweredefinedwhereyouexpected.•Applyinginitialconditions,boundaryconditions,etc.L3.18CoupledEulerian-LagrangianAnalysiswithAbaqus/ExplicitTips•ToinitializeamaterialinseveraldifferentregionsintheEuleria