汽车仪表板建模规范

Q/SZJ191001-2017仪表板建模规范SpecificationOfInstrumentPanelModeling20XX20XX-XX-XX实施20XX-XX-XX发布XXXX汽车工程技术有限公司发布Q/SZXX-X-2017仪表板建模规范范围本标准规定了仪表板建模方法及结果处理方法。本标准适用于CAE部门仪表板建模。规范性引用文件无。术语和定义无。摘要IP通常包括（CCB、中控台等等），它对内饰车身刚度影响很大。此外，IP还包括许多代表非结构质量体系的内饰零件。AnIPassemblytypicallyincludesstructuralmembers(crosscarbeam,tunnelbraces,etc.)significanttothetrimmedbodystiffness.Inaddition,anIPassemblyincludesmanytrimitemsthatrepresentnon-structuralmassinthesystem.本文描述了仪表板的建模规范，用于整车级的NVH分析。这些标准也可以参考中控台的建模。Thisdocumentdiscussesmodelingguidelinesforinstrumentpanelassembliestobeusedinfullvehiclesystemlevelnoiseandvibrationanalysis.Theseguidelinescouldalsobereferencedforthemodelingofinteriorconsoles.流程图ProcessFlowDiagram无工具描述ToolDescription有限元模型的建模需要用到有限元前处理软件。分析需要用NASTRAN软件。模型的检测与验证需要用有限元后处理软件。Thefiniteelementmodelshouldbedevelopedinanapprovedfiniteelementmodelingpreprocessor.AnalysisshouldbedoneusingNASTRAN.Modelcheckingandverificationshouldbedonewithanapprovedfiniteelementpostprocessor.目前有限元前、后处理软件有HyperMesh和HyperView。Thecurrentlyapprovedfiniteelementpre-andpostprocessorsareHyperMeshandHyperView.建模和分析过程Modeling/AnalysisProcedure单位Units分析中所用单位制如下所示:Theunitsusedintheanalysisareasfollows:力(Force) 牛顿(N)质量(Mass) 吨(Ton)长度(Length) 毫米(mm)时间(Time) 秒(Second)内容Contents本文中的有限元模型按结构划分应包括，几何形状和材料特性，以及精确的质量和惯量组成。Thecontentsofthefiniteelementmodelshouldincludeastructuralrepresentation,composedofthegeometryandmaterialproperties,aswellasaccuratemassandinertiarepresentation.坐标系CoordinateSystems根据7.4描述的建模指导选择合适的坐标系。Seesection7.4formodelingguidelinesofcoordinatesystems.建模技巧ModelingTechniques简化建模技巧拟。SimplifiedModelingTechnique除了CCB、中控台和重要的结构构件（如果它们存在），在IP建模中用一个或几个CONM2单元来表示质量、惯量并用它们来模拟内饰。CONM2单元应该加载在构件的CG位置。RBE3单元是用于连接在IP或车身结构上的CONM2单元的连接位置。CONM2单元应该建在RBE3单元的中心节点上。RBE3单元的从点应使用6个自由度，主点应使用1-3自由度。Exceptforthecrosscarbeam,tunnelbracesandsignificantstructuralmembers(iftheyexist),theIPassemblyismodeledusingoneorseveralCONM2elementstorepresentmassandinertiaofthetrim.TheCONM2elementsshouldbelocatedatthecomponent’sCG.RBE3elementsareusedtoconnecttheCONM2elementtotheattachmentlocationsontheIPorbodystructure.TheCONM2elementshouldbeplacedatthedependentgridoftheRBE3elements.AllsixDOFsofdependentnodeoftheRBE3elementshouldbeused,andDOF1-3areusedfortheindependent.注意：简化的IP模型是很容易创建，需要很少的计算机资源运行。但是它不考虑IP的刚性和它的局部模态。有时候它可能会导致局部模态在实际结构中可能不存在连接位置。WARNING:ThesimpleIPmodeliseasytocreateandneedslittlecomputerresourcestorun.However,itdoesnotconsidertheIPflexibilityanddoesnotrepresentIPlocalmodes.Occasionallyitmaycauselocalmodesattheattachmentlocationswhichmaynotexistintherealstructure.详细建模技巧DetailedModelingTechnique对于这部分的详细模型的建立过程，需要特别注意以下事项：用壳单元模拟整个IP骨架。用壳单元模拟整个IP附件。模型的泡沫材料质量作为非结构质量（NSM）覆盖在IP的泡沫上。模型的IP附件内饰板和用集中质量表示出风口和格栅。模型的HVAC，鼓风机，收音机，组合仪表尽量用壳单元，用PSHELL卡片输出非结构质量。不要用RBE3和集中质量来表示这些零件。确保所有的锁扣和铰链（例如手套箱）模型的模态不超过60Hz。锁扣应该用实体单元建模，锁于锁壳连接用RBE2单元，自由度1-3。铰链模型的建模应按下面方法：模型中不存在任何不支持的内饰零件。在车身模型中的连接口零件通常不完全连接。不要人为的约束这些零件。这些零件最好用非结构质量表示。Forthebuildingofdetailedmodelsforthiscomponent,payingparticularattentiontothefollowingitems:•ModeltheentireIPstructureusingPlateelements.•ModeltheentireIPretainerusingplateelements.•Modelthefoammassasnon-structuralmass(NSM)overtheareaofIPcoveredwithfoam.•ModeltheIPretainertrimpanelanduseconcentratedmassestorepresentventsandcontrols.•ModeltheHVAC,BlowerMotor,Radio,andInstrumentcluster,ascloselyaspossiblewithShellelementsandusedistributedNSMinthePSHELLcard.DonotuseRBE3sandConcentratedMasstorepresentthesecomponents.•Ensurethatanylatchesandhinges(i.e.glovebox)aremodeledcorrectlysuchthatnoartificialmodesofthesecomponentsexistupto60Hz.LatchesshouldbemodeledwiththesolidelementsofthestrikerconnectedwithRBE2sinDOF123tothesolidelementsofthelatchplate.HingesshouldbemodeledwithaseriesofRBE2salongthelengthofthehingeusingthemethodshownbelowDonotleaveanyunsupportedtrimcomponents(i.e.HVACductsormodules)inthemodel.Inthebodymodelthereistypicallynotsufficientattachmentprovidedfortheinterfaceofthesecomponents.Donotartificiallyconstrainthesecomponents.Thesecomponentsarebetterrepresentedasnon-structuralmass.假设和限制Assumptions/Limitations无载荷和边界条件Loads/BoundaryConditio