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TrainingManualDYNAMICS11.0预览在这个例子中,将研究球体和矩形盒接触碰撞的柔体动力学问题：–首先做模态分析以确定结构固有频率–包括接触和塑性变形的柔体动力学分析TrainingManualDYNAMICS11.0Demo:打开模型•打开“ImpactProblem.wbdb”文件•FromtheProjectpage,openthe“ImpactProblem”SimulationDatabaseExaminethepartsinthe“Geometry”branch.Notethatthe“plate”parthasanelasto-plasticbilinearisotropichardeningdefinitionthatcanbeviewedinthe“EngineeringData”page.Frictionalcontactbetweenthe“ball”and“plate”partshasalreadybeendefined.Meshcontrolshavealsoalreadybeenaddedtocreateathin-solidmesh(solid-shellelementtype)withafinermeshdensitynearthepointofimpact.•用单位设置工具,确认目前单位制是“Metric(mm,kg,N,°C,s,mV,mA)”TrainingManualDYNAMICS11.0Demo:定义模态分析对“plate”部件做模态分析，以确定结构的固有频率。•从工具栏中添加“NewAnalysisModal”•详细设置菜单“AnalysisSettings,”change“MaxModestoFind:20”TrainingManualDYNAMICS11.0Demo:添加约束•在“Modal”分枝中,从工具栏中选择“SupportsFixedSupport”ANamedSelectionhaspreviouslybeencreatedtodesignatethebaseofthepartthatistobefixed.•IntheDetailsviewof“FixedSupport,”change“ScopingMethod:NamedSelection”andthenuse“NamedSelection:Fixed_Base”TrainingManual碰撞问题作业1BTrainingManualDYNAMICS11.0Demo:RequestModalResults•选择“Solution”分支,插入“DeformationTotal”•Sinceonlythe“plate”partisofinterest,the“ball”partneedstobesuppressed•Right-clickon“Geometryball”andselect“Suppress”.Notethattheassociatedcontactpairwillalsobeautomaticallysuppressed•求解Themodelshouldtakelessthanaminutetosolveona3.2GHzPC.TrainingManualDYNAMICS11.0Demo:观察模态分析结果•选择“TotalDeformation”来观察阵型，可以从“Timeline”中观察阵型。•Selectthe“SolutionInformation”branch.Searchfortheword(Ctrl-F)“ParticipationFactor”,thenscrolldowntothelistofparticipationfactorsinthey-direction.Notethatmodesupto#6(~450Hz)havehighparticipationfactors.FromtheearlierguidelinepresentedinSectionB,wewilluseatimestepof1/20for~1e-4second,basedonthismode.(Thereareotherhigher-frequencymodesthatmaycontributetotheresponseofthesystem,butinthissimpleexample,weareonlyconsideringthefirstsixmodes.)TrainingManualDYNAMICS11.0Demo:改变分析类型改变分析类型“ModaltoFlexibleDynamicAnalysis”•选择“Modal”分枝,在详细设置窗口中改变“AnalysisType:FlexibleDynamic”•Intheflexibledynamicanalysis,theballwillimpacttheplate,sothe“ball”partneedstobeunsuprressed.•Right-clickon“Geometryball”andselect“Unsupress”NotethattheassociatedcontactregionshouldalsoautomaticallybecomeunsuppressedTrainingManualDYNAMICS11.0Demo:分析设置•选择“AnalysisSettings”分枝.在详细设置窗口中改变如下参数:–StepEndTime:5e-3–InitialTimeStep:1e-4–MinimumTimeStep:1e-4–MaximumTimeStep:1e-3仿真时间是5milliseconds.基于之前的模态分析结果,0.1milliseconds是一个合适的时间步长.TrainingManualDYNAMICS11.0Demo:初始条件Thespherewillhaveaninitialvelocityof(0,5m/s,1m/s)•Selectthe“InitialCondition”branch.Inthedetailsview,setthefollowingparameters:–InputType:ConstantVelocity–DefineBy:Components–YComponent:-5000–ZComponent:1000–ScopingMethod:GeometrySelection–Geometry:[Body-selectthe“ball”part]Sincenothingwasspecifiedforthe“plate”part,thatpartisassumedtobeinitiallyatrest.TrainingManualDYNAMICS11.0Demo:RequestResults•Afterselectingthe“Solution”branch,inadditiontotheexisting“TotalDeformation”result,addotherresultsthatmaybeofinteresttoyou:–StressEquivalent(von-Mises)–StrainEquivalent(von-Mises)–StrainEquivalentPlasticStrain•Selectthe“Solution”branch,thenadd“ProbeForceReaction”.IntheDetailsview,select“BoundaryCondition:FixedSupport”TrainingManualDYNAMICS11.0Demo:求解柔体动力学•Clickonthe“Solve”icontoinitiatethesolutionThisflexibledynamicanalysisinvolveslargedeflectioneffects,contact,andplasticity,henceitisnonlinear.Thesolutioncanbemonitoredbyselectingthe“SolutionInformation”branch,thechangingthe“SolutionOutput:ForceConvergence”intheDetailsview.Thisanalysistakesapproximately30minutesona3.2GHzPC.TrainingManualDYNAMICS11.0Demo:观察结果•Afterthesolutioniscomplete,reviewresultsAplotandanimationof“EquivalentStress”isshownontherightTrainingManualDYNAMICS11.0Demo:添加变形图•Changetheselectionfilterto“BodySelect”andonlyselectthe“plate”body.Then,underthe“Solution”branch,insert“DeformationDirectional”.IntheDetailsview,change“Orientation:YAxis”.Right-clickand“RetrieveResults”Notethattheperiodfrommintominis(4.6-1.5=3.1msorafrequencyof320Hz.Thisisinlinewithourexpectationsofexcitingmodesupto450Hz.Ifthetimestepwasmuchlarger,thedynamicresponsemaynothavebeencapturedassmoothly.TrainingManualDYNAMICS11.0Demo:添加图表•Selectboth“EquivalentPlasticStrain”and“DirectionalDeformation”,thenclickonthe“NewChartandTable”iconontheStandardToolbar.•Inthenewlyadded“Chart”branch,change“OutputQuantitiesEquivalentPlasticStrain(min):Omit”intheDetailsviewNotetheplotofthey-deformationandmaxequivalentplasticstrain.Duringthesimulation,theequivalentplasticstrainincreasesupuntil0.3ms,whereitremainsrelativelyconstantuntil1.1ms,whereuponitincreasesmoreuntilreachingthemaxplasticstrainvalueof2.6%.Afterthat,the“ball”haslostcontactwiththe“plate,”sonofurtherplasticstraindevelops.TrainingManualDYNAMICS11.0