NVH分动器建模规范

Q/SZJ191001-2017NVH分动器建模规范ModelingSpecificationOfTransferCaseForNVH20XX20XX-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-2017NVH分动器建模规范范围本标准规定了NVH分动器建模方法。本标准适用于CAE部门分动器NVH模型建模。规范性引用文件下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件，仅注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本（包括所有的修改单）适用于本文件。有限元网格建模规范CAE整车模型命名规范术语和定义无。摘要Abstract本规范是关于分动器的NVH建模。根据分析频率范围和分析类型不同，建模方式可分为简化和详细建模，详细信息见后。ThisdocumentprovidestheproceduresformodelingofthetransfercasesubsystemforNoiseandVibrationanalysis.Dependingonthefrequencyrangeandtypeofanalysistwodifferentmodelingtechniquesaredescribed.Theyarethesimplifiedanddetailedmethod.Furtherinformationcouldbefoundinfollowingsectionsandinusedanalysisprocedure.工具描述ToolDescription仿真分析过程中需要用到的如下软件:Thefollowingsoftwarefacilitatestheanalyticalsimulationprocess:前处理(Preprocessors):Hypermesh求解器(AnalysisCode):MSC.Nastran后处理(Postprocessors):HyperView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包含两种建模方式：简化和详细，采用哪种方式建模由分析决定。Thisprocedureincludestwodifferentmodelingtechniques,simplifiedanddetailed.Whichoneistobeuseddependsontheanalysisthatshouldbeperformedonthemodel.坐标系CoordinateSystems见随后的建模说明Seethesectionformodelingguidelinesofcoordinatesystems建模技巧ModelingTechniques分动器将动力从变速器输出轴分配到前后传动轴。一般安装在变速器后端，有时还带有一个分动器适配器。在分动器中有齿轮/链与前传动轴连接，后传动轴直接与变速器输出轴相连。Thefunctionofthetransfercaseistosplitthepowerfromthetransmissionshaftintothefrontandrearpropshafts.Itistypicallyassembledattherearofthetransmission,sometimeswithatransfercaseadapter.Insidethetransfercasetherearegears/chainstoconnecttheinputtransmissionshafttothefrontpropshafts.Therearpropshaftsisconnecteddirectlytothetransmissionshaft.图1分动器模型简化建模SimplifiedModelingTechnique对于低于200Hz的NVH问题，可使用简化建模方法。第一步——定义几何和质量参数需要四个点的位置，分别是变速箱连接点、后传动轴连接点、前传动轴连接点和分动器质心。质量和转动惯量定义在质心处。第二步——定义局部坐标系和轴承点局部坐标系原点是变速箱连接点，后传动轴连接点是Z轴，前传动轴连接点位于XZ平面。这三个连接点分别建立同心的轴承点。第三步——定义连接在轴承点上创建RBE2单元，并释放6自由度（绕Z轴）。所有轴承点用RBE2与分动器的质心相连。使用CBEAM单元来连接变速箱连接点和后传动轴连接点。建立MPC方程来定义变速箱连接点与前传动轴连接点之间转动关系。MPC的系数由齿轮传动比决定。第四步——定义显示动画单元用PLOTEL单元来表示分动器的轮廓，并与质心用RBE2相连。FormostNVHproblemsoflessthan200Hz,thetransfercasecouldbemodeledusingthesimplifiedtechnique.Step1–Definegeometry&masspropertyFourgridlocationsareneeded.TheyaretheTransmissionShaftinterfacepoint,TheRearPropshaftinterfacepoint,TheFrontPropshaftinterfacepointandtheCGofthetransfercase.ThemassandinertiaaredefinedattheCGgrid.Step2–DefinelocalcoordinatesystemandbearingpointThelocalcoordinatesystemisdefinedwiththeTransmissionShaftinterfacepointastheorigin,theRearPropshaftinterfacepointontheZ-axisandtheFrontPropshaftinterfacepointlyingontheXZplane.Foreachofthethreeinterfacepointsacoincidentpointiscreatedtobeusedasbearingpoint.Step3–DefineconnectionsAnRBE2iscreatedtoconnecteachinterfacepointwithitsbearingpoint.TherotationalDOF(6)shouldbefreedsothattheshaftscanrotatefreely.ThebearingpointsareattachedtotheCGwithRBE2.ArigidbutmasslessCBEAM(ormorethanone)iscreatedtoconnecttheTransmissionShaftinterfacepointtotheRearPropshaftinterfacepointtotheTransmissionShaftinterfacepoint.ThecoefficientoftheMPCarebasedonthegearratiobetweenthosetwointerfacepoints.Step4–DefineanimationelementsRBE2canbecreatedoneachshaftinterfacepointforanimation.PLOTELscanalsobecreatedtorepresenttheboundaryofthetransfercaseforanimation.ThePLOTELsshouldbeconnectedtotheCGpointwithRBE2.图2简化分动器模型详细建模对于超过200Hz的NVH问题，可使用详细建模方法。ForNVHproblemshigherthan200Hzorifshellmodesoftransfercasearedesired,thedetailedmodelingtechniqueshouldbeused.详细建模的目的是为了得到分动器的结构模态。外铸件用体单元建模，内部用位于质心的质量点。轴承点可用轴承表面与铸件用RBE3相连表示。其它和简化建模一样。Thepurposeofthedetailmodelistocapturestructuralmodesofthetransfercase.Theoutsidecastingcanbemeshedwithbrickelementsor10-nodetetras.TheinternalpartscanberepresentedbylumpedmassattheCG.ThebearingpointsaretobeconnectedtothecorrespondingbearingsurfaceofthecastingviaRBE3.Otherthanthese,therestoftheconnectionsaresimilartothesimplifiedmodel.详细模型建模技巧DetailedModelingTechniques参考《有限元网格建模规范》.假设和限制Assumptions/Limitations假设Assumptions这种建模方法假定所有组件的行为都是线性的。不模拟非线性行为。Thismethodofmodelingassumesallcomponentsbehaveinalinearfashion.Nonlinearbehaviorisnotsimulated.限制Limitations无。载荷和边界条件Loads/BoundaryConditions无。结果Results无。性能要求PerformanceRequirements无。分析要求ANALYSISREQUIREMENTS无。参考文件DOCUMENTATION无。联系人CONTACTS无。例子EXAMPLES$Coordinatesystem$CORD2R68100002178.59930.528.23512614.6530.481.5+2189.9-195.4434.5$CGGRID68067092500.20.528.6810000CONM2681000068067090.00+0+0.00+00.00+00.00+00.00+00.00+00.00+0$InputfromtransmissionGRID68000032178.59930.528.23516810000GRID681000068100000.00+00.00+010.6810000GRID681000168100000.00+00.00+010.6810000CBEAM68100016810000680000368100011.0.00+00.00+0RBE2681000268067091234566810000PLOTEL680000068067096810000PLOTEL680000168000036810001RBE268100036810000123456810001$OutputtoRearpropGRID68000002614.6530.481.56810000GRID681000268100000.00+00.00+0428.54836810000GRID681000368100000.00+00.00+0428.54836810000CBEAM68100046810000680000068100031.0.00+00.00+0RBE2681000568067091234566810002PLOTEL680000268067096810002PLOTEL680000368000006810003RBE268100066810002123456810003$OutputtoFrontpropGRID68000012189.9-195.4434.56810000GRID68100042189.9-195.4434.56810000RBE2681000768067091234566810004PLOTEL680000468067096810004RBE268100086810004123456800001$MidpointofthroughshaftGRID681000568100000.00+00.00+0219.27416810000CBEAM68100096810000681000168100051.0.00+00.00+0CBEAM68100106810000681000568100031.0.00+00.00+0PLOTEL680000568100016810005PLOTEL680000668100056810003PBEAM681000068100001000.200000.200000.0.00+0400000.MAT168100002.07+8.287.80-12$AttachmenttofrontoutputGRID68100066810000243.45140.00+0219.27416810000GRID68100076810000243.45140.00+0219.27416810000RBE2681001168067091234566810007PLOTEL680000768067096810007RBE268100126810007123456810006CBEAM68100136810000681000668000011.0.00+00.00+0PLOTEL680000868100066800001$ChainMPC6810000681000561.68100066-1.$AnimationGRID681000868100000.00+050.219.27416810000RBE2681001468100051234566810008PLOTEL680000968100056810008GRID68100096810000243.4514-50.219.27416810000RBE2681001568100061234566810009PLOTEL680001068100066810009GRID6810010