整車(chē)FEM建模手冊(cè)-絕密

PAGEPAGE24用于碰撞被動(dòng)安全性CAE分析FEM建模手冊(cè)車(chē)身模型建模要求一般要求GeneralRequirements1.Thepartsshallbemodelledusinglinear(3or4noded)shellelements.2.Thepartsshallbemodelledonthemidsurface.Ifthedeliveredgeometryisnotamidsurfacerepresentation,thegeometryshallbemodifiedtorepresentthemidsurface.3.Noelementsareallowedtocrossthe“symmetry”liney=0(nodesshallbepositionedony=0)4.Theshellelementsshallbeconsistentlydefined.5.Thepartsshallbemodelledinthefollowingunitsettings:Lengthinmillimetres(mm)Timeinsecond(s)MassintonneForceinNewton6.EachpartshallhaveoneuniquePID,withthefollowingexceptions:PartsmadeoftailoredblanksshallbedividedintodifferentPIDsaccordingtothedifferentthicknessandmaterialqualitiesoftheparts.ExtrudedpartsshallbedividedintodifferentPIDsaccordingtothedifferentthicknessandmaterialsofextrusion.Thethicknessatdifferentlocationsonacast/mouldedpart7.Thepreferrednamingconventionasbelow:ST3700=1234567_A1A_3.5_B-Pillarmaterialdrawingnodrawingrevthicknesspartname8.AllpartswithidenticalmaterialspropertiesshallrefertothesameMID.9.Onemodelshallbeusedforallcrashsimulation建模要求MeshingGuideline1.Deformationareashallbemeshwithaaveragelength10mm.Deformationareashallbemeshwithaminimumlengthofnotlessthan5mm.Maximumlengthshallnotexceed12mm.注：變形區(qū)域：正面碰撞：A柱與B柱中間位置以前的所有零件及其某些零件的前部（車(chē)門(mén)除外），另外前端吸能部件，包括縱梁前段、翼子板支撐結(jié)構(gòu)等的平均單元長(zhǎng)度為8mm；側(cè)面碰撞：前后從A柱至C柱（包括A柱與C柱），橫向左半部所有零件及其某些零件的左半部（框內(nèi)的零件及其某些零件的框內(nèi)部分）；背面碰撞：C立柱（包括C立柱）以后的所有零件及其某些零件的后部（車(chē)門(mén)除外）。2.Noneformationareashallbemeshwithaaveragelength15mm.Allpartsshallbemeshwithaminimumlengthofnotlessthan5mm.Maximumlengthshallnotexceed18mm.3.NopenetrationsareallowedintheFEmodel.FEmodeshallbeglobalpenetrationcheck.(partthicknessscaleis0.65.)4.Elementtype:QUAD4andTRIA3(max10%ofthefullmodel)5.ElementCheck:Aspectratio<3.0Skewness<60Warping<15CrashTimeStep*＞8.1e-07InternalAngleMinMaxQUAD40140TRIA30120Jacobian>0.5*CrashtimestepforpartB-pillarsystem,longitudinal,bumpersystemis6.0e-7Thepartshallbecompletelymeshed.Un-meshedareasshallnotexistA“freeedge”checkshallbeperformedtoverifythatthereareno”cracks”inthemesh.A“shellelementnormal”checkshallbeperformedtoverifythatthenormalsareconsistentlydefinedNoduplicategridpointnumbersshallexist.NoduplicateelementnumbersshallexistNoduplicatestructuralelementsshallexist.Aduplicateelementisdefinedasanelementofthesametypeandattachedtothesamegridpointsasanotherelement.Avoidpackingtrianglestogethertothesamegridpoint6.ModellingoffilletIftheradiusofthefilletissmallerthan5mm–norepresentationofthefilletIftheradiusofthefilleris=/>5mm,aminimalofoneelementinfilletismodelled.7.ModellingofflangesSpotweldedflangesshallbemodelledaccordingtothefigurebelow:Trytokeeptheoriginalangleoftheflange.In(a),theflangehasanewangle,whichisnotrecommended.Therecommendedpracticeistomodeltheflangeasin(b).Thisisforassemblyreasons;flangeswithlargeangulardifferencesmayyieldpoorweldingelements8.ModellingofhemflangesHemflangescanberecognizedbythatthepartisfoldingarounditself(seefigurebelow)Hemflangesshouldbemodelasfigurebelow:9.Modellingofholesa)BoltholesForboltholes,6ormorenodesaroundisrequiredaroundtheperimeterofthebolthole.Theouterperimeterofwashers,distancesandnutsintheboltjointshallbeprojectedonthepartandmodelledusingpreferably6ormorenodesaroundtheprojectedperimeter.Incaseswheretheaverageelementlengthissmallcomparedtothesizeofthewasher,itisallowedtousemorethanonerowofelementsbetweentheouterandtheinnerwasherperimeter.Iftheouterperimeterofwashers,distancesandnutsintheboltjointisnotknown,acirclewithcentreinpointCandadiameterof2.0×Dmin(Dmin=minimumdiameterofbolthole)maybeused.Itisallowedtoslightlymodifytheperimeterofeithertheboltholeortheprojectedoneofwashers,distancesandnutsinthebolt,ifthatimprovestheelementqualityaroundthebolthole.Iftheminimumdiameteroftheholeissmallerthantheminimumelementlength(5mm),theholeshallnotbemodelled.b)RivetholesRivetholesshallnotbemodelled10.ModellingofspotweldSpotweldaremodelledasPLINKinpamcrashmodel.PLINKisdefinedbyoneindependentnodedescribingthelocationofthespotweldaswellasthepartswhichisneededtobespotwelded.ThelocationofspotweldtobedefinedinVIPfilePLINKForarcwelding,thepositionofthearcweldingshallberepresentedbyanode.ThisnodetobemodelledwithTIEDCONTACT(TYPE32)–“NodetoElement”12.ModellingforglueModellingofglueisbySOLID(PENTA/HEXA).Thesolidistobemadegridtogridtoitsconnectingparts.13.鉸接厚度不同的鑄造鉸鏈體用SOLID(PENTA/HEXA)單元模擬，其余用殼單元模擬。較銷(xiāo)用spring單元模擬，spring單元只有三個(gè)移動(dòng)自由度方向的剛度，三個(gè)轉(zhuǎn)動(dòng)自由度方向的剛度為零。較銷(xiāo)與鉸鏈體之間用rigid單元連接。動(dòng)力傳動(dòng)系統(tǒng)模型建模要求（1天）GeneralEachpartoftheenginecomponentstobemodelledseparatelyintodifferentPIDsEnginepackagecanbeseparatedintoafewdifferentcategoriesasperbelow:a)ENGINE:EngineblockCylinderHeadCylinderCoverOilpanb)AGGREGATES:GeneratorWaterpumpAirconditioningcompressorOilFilterPulleys,etcc)INJECTIONSYSTEM:ManifoldAirductAirfilterIgnitionsystemd)ENGINEBAYCOMPONENTS:WatertanksBatteryBrakebooster,brakecylinder,brakefluidtankABSFuseboxe)GEARBOXGearboxDriveshaftDifferentialf)EXHAUSTSYSTEM:ExtractorCatalyticconverterPipesSilencersBrackets/Hooksg)ENGINEMOUNTINGh)COOLER:Radiator,AirconditioncoolerFan,CageBracketsetcMeshingGuideline1.EngineMeshingsize15~20mmOnlyoutersurfaceismeshToavoidhourglassissues,theribsaretobemodelledwith2elementrows.發(fā)動(dòng)機(jī)本體在分析中作為剛體處理，但必須保證單元質(zhì)量，為此可以作適當(dāng)?shù)膸缀魏?jiǎn)化處理2.AggregatesMeshingsizeis10mmThesepartsaremostlynotdeformablebuttherecouldbeapossiblerupturetoitsbracketsBracketshavetobemodelledmiddlesurfacewithtruethicknessAggregatescanbemodelwithoutershell.Toavoidhourglassissues,theribsaretobemodelledwith2elementrows.3.InjectionsystemandenginebaycomponentsMeshingsizeis10mmPartstobemodelledwithoutersurface4.GearboxMeshingsizeis15~20mmPartstobemodelledwithoutersurface5.ExhaustsystemMeshingsizeis10mmExhaustmanifold/extractorandcatalyticconverterismodelledwithoutershellPipes,silenceranditsribsandtobemodelwithmiddlesurfaceAllpartsforexhaustsystemtobeconnectedgridtogrid.Thecompartmentinthesilencerhastobemodelledinrib(pleaseseefigurebelow)6.EnginemountingMeshingsizeis10mmEnginemountingtobemodelledwithmiddlesurface橡膠墊采用彈簧單元模擬7.CoolerMeshingsizeis10mmFan,fancage,pipesneedtobemodelledwithshellsHoneycombonthecooler/radiatortobemodelledwithSOLIDelements.Aminimumof3layersofsolidismodelledoverthethicknessofcooler.底盤(pán)系統(tǒng)模型建模要求一般要求底盤(pán)系統(tǒng)模型包括轉(zhuǎn)向系統(tǒng)轉(zhuǎn)向拉桿轉(zhuǎn)向助力器齒輪結(jié)構(gòu)轉(zhuǎn)向柱轉(zhuǎn)向盤(pán)支架懸架系統(tǒng)輪胎羊角擺臂彈簧減振器橡膠墊建模要求1、轉(zhuǎn)向系統(tǒng)轉(zhuǎn)向拉桿用R和BEAM單元模擬轉(zhuǎn)向拉桿套筒采用尺寸為mm殼單元模擬轉(zhuǎn)向助力器與齒輪系統(tǒng)只建殼體，采用尺寸為mm殼單元模擬轉(zhuǎn)向柱采用BEAM單元模擬轉(zhuǎn)向柱套筒采、支架、轉(zhuǎn)向盤(pán)用尺寸為mm殼單元模擬、懸架系統(tǒng)懸架系統(tǒng)輪胎采用氣袋模型模擬，因此采用尺寸完15MM的殼單元建立封閉體，輪轂采用尺寸為20MM的殼單元作彈性體處理。連接擺擺臂、輪轂、懸架、轉(zhuǎn)向拉桿等的羊角采用RIGID單元作為剛性體處理，在其原點(diǎn)附質(zhì)量單元，其質(zhì)量為羊角本身質(zhì)量加制動(dòng)系統(tǒng)的質(zhì)量。板殼件擺臂采用殼單元，實(shí)體件擺臂采用SOLID單元。螺旋彈簧和橡膠墊的彈性屬性采用BAR單元模擬，螺旋彈簧外形輪廓采用殼單元模擬，周?chē)鷱椥圆牧咸幚?。減振器外形輪廓與彈簧托架采用殼單元模擬。座椅模型建模要求MeshingGuidelineSeatpositionTheseatmustbepositionedinthemiddleforbothslidingrailaxis