14-瞬态动力学分析

瞬态分析CasterWheelTest,Workshop1目标,Ourgoalistodeterminethedynamicresponseofacasterwheelexposedtoasideimpactsuchashittingacurb.ThismaybesimulatedinaphysicaltestbydroppingaheavyStrikerToolonthesideofthewheel.Thedroppedweightrepresentssideimpactonthewheel.TheWheelandStrikerToolaremadeofSteel.AssumethefarfaceoftheWheel/Axleisconstrained.AssumethesidesoftheStrikerareconstrainedtoslideupanddownverticalrails.Assumeadampingratioof0.02(i.e.2%),ConstrainEnd,StrikerTool,Wheel,Workshop1起始页,FromtheWorkBenchProjectLauncherstartSimulation.ifalreadyinSimulationuseFileNewFortrainingpurposes,clickon“No:donotsaveanyitems”OnceinSimulationclickonToolBarGeometryFromFile.tobrowseforandopencaster_test2.agdb,Note:WemodeledtwoStrikerToolshere.Theupperoneisattheinitialdropheight.TheloweroneisatimpendingcontactwiththeCasterWheel(onlyoneisusedinthesimulation),Workshop1设置,WhentheGeometryhasloaded,choose“FlexibleDynamics”ontheMapofAnalysisTypesClickonNewAnalysisMapof.ifnecessary.Enter.001(seconds)astheendtimeClickOKChoose/Verifythemetricunitsystem.“Unitsmetric(m,kg,N,)”,4,2,1,3,.001,Workshop1-Preprocessing,Thefirstpreprocessingstepsaretosuppresstheupperstrikerandspecify/verifythatSteelisassigned.FirstSuppresstheupperStriker.ExpandthegeometryBranch,anddeterminewhichpartistheupperStriker.RMBSuppressBodyWewillincorporatethelowerStrikerinthesimulationonly.WewillapplyaninitialvelocitytothelowerStrikertoaccountforitsmomentumduetothedropheight&force.NowVerifythatSteelisassigned.ClickonthefirstpartintheexpandedGeometryBranchIntheGraphicsWindow,RBMselectAll(parts)InDetails,choose/verifythatSteelisassignedtoalltheparts.,6,5,Workshop1-Preprocessing,DefinethecontactbetweenthebottomoftheStrikerToolandthetopEdgeoftheCasterWheelLMBonConnectionsintheOutlineTree.InsertManualContactRegionUseFaceselectSelectandthetoprimofthewheelundertheStrikeras“Target”.SelectandthebottomoftheStrikerToolas“Contact”.Change“UpdateStiffness”to“EachEquilibriumIteration”,8,7,9,Workshop1环境,Applyconstraintsontheendoftheboretoopposeloadsonthewheel.WithintheFlexibleDynamicBranchInsertFixedSupportUseFaceSelect,LMBandpickfourannularsurfacesonthebottomoftheaxlehole.Rotatethewheelsoyouarelookingatthebottomofthewheel(thesidefacingawayfromthestrikertooling)UseFacePickandpickthefourfaces.CollectthefoursurfacesbyholdingdowntheLMBandsweepingthecursoroverall4quadrants,oruse+LMB,orboxpickmethods.Click,11,12,Workshop1环境,TheStrikerToolisguidedonrailssoitcanonlytravelupanddownwhendroppedonthewheel.InsertFrictionlessSupportUseLMBandpickallfoursidesoftheStrikerToolblock.Rotatetheblockandusefacepickandasnecessarytopickallfacesonthesides(butnotthetoporbottom)Note:The“foursides”oftheblockmayconsistofmorethan“four”totalfacesdependingonhowthe(CAD)geometrywasoriginallygenerated.,aFace,aFace,14,13,Workshop1环境,ApplyagravityinertialloadRMBInsertStandardEarthGravitytoaccountforweight(mass)andtoacceleratetheStrikerdownwardtowardstheWheel.IntheDetailswindow,changetheDirectioninthiscaseto+X(lookattheXYZTriadtounderstandglobalorientation),15,16,Workshop1环境,ApplyaninitialvelocityontheStriker.IntheOutlineTree,clickonInitialCondition.InDetails:Change“AtRest”to“ConstantVelocity”UseBodySelectandpickandApplytheStrikerPart.ChangetheDirection“DefinedBy”to“Components”Enter10m/sfor“X”initialvelocityisassignedtothepickedStrikerbutnottheCasterWheel,17,18,Workshop1求解设置,CheckonAnalysisSettingsintheOutlineTreeIntheDetailswindow,definetheanalysissettingsinthe“timedomain”Verify“1”forNumberofStepsVerify“1”forCurrentStepNumberVerify“.001”forStependtimeEnter“.0001”forInitialTimeStepEnter“.00003”forMinimumTimeStepEnter“.0002”forMaximumTimeStep,19thru24,Concerningthetimestepentries(steps19thru24)itmaytakesomehandcalculationsand/ortrial&errortofindvaluesthatareappropriateforthescaleandseverityofyournon-linearproblem.,Workshop1DynamicSolution,WiththeBranchesprepared,wearereadytosolvetheDynamicsimulation.Asafinalcheckverifythestatussymbolsnexttothebranches.Allbranchesshouldhaveeither:Lighteningbolt(ready)Greencheckmark(complete)Solve.ToolBarButtonSolveNote:solvingfromtheToolbar“thunderbolt”causesallunsolvedbranchestobesolved.Hadwewishedtosolveonlyonebranchwecouldhavehighlightedonlythatbranchorobjecttobesolved.,25,The“mousemenu”SolvemayonlysolveasingleobjectandnotevaluateobjectselsewhereintheOutlineTree,Workshop1结果,AftertheSolutioniscompletedreviewtheresults.VeryimportantinmanyproblemslikethisSetResultScaleto“1.0(TrueScale)“Insertadditionalsolutionobjectsofinterest,.Workshop1结果,TogetanoverallviewoftheDynamic(transient)resultsstepthrutheTimeLineforeachresultplotofinterest.EvaluateanyobjectsthathavelosttheirGreenCheckmark(possiblybecausetheDisplaytimehaschangedduetochangesintheTimeline.RemembertoAnimate(Play&Stop)themodefromtheTimelinewindow.Youcantypicallyrotatethemodelduringanimationtoo.RemembertotrytheVectorGraphics