整车拖钩牵引强度分析规范

Q/SZJ191001-2017整车拖钩牵引强度分析规范SpecificationofStrengthAnalysisforFullVehicleTowingHook20XX20XX-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整车拖钩牵引强度分析规范范围本标准规定了轻型车前后拖钩牵引强度分析的方法和要求。本标准适用于CAE部门整车拖钩牵引强度分析。规范性引用文件GB32087-2015轻型汽车牵引装置术语和定义拖钩固定或安装在汽车上，通过拖绳，拖缆或拖杆等装置进行连接，实现车辆牵引或被牵引的部件。摘要Abstract本规范规定了整车前后拖钩强度分析的模型建模要求，边界约束，工况载荷和结果评价方法。Thespecificationprovidesthestrengthanalysismethodsandrequirementsforfrontandreartowinghook.流程图ProcessFlowDiagramYesYesNo截取/更新Nastran模型Cut/updateNastranmodel转化Abaqus模型TransformAbaqusmodel更新材料和焊点Updatematerial&spot创建接触对Setcontactpairs施加载荷和约束Load&constrain提交计算Submitcomputer满足要求？OK？结束End优化Optimization图1流程图Fig1ProcessFlowDiagram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):Abaqus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(N)质量(Mass) 吨(Ton)长度(Length) 毫米(mm)时间(Time) 秒(Second)内容Contents分析模型包括拖钩总成，截取的白车身模型，如拖钩在副车架上，还应包括副车架。截取的前后拖钩有限元分析模型如图2和图3所示：TheanalysismodelcontentincludestheFErepresentationoftowinghookassemblyandthecuttingBIWmodel.Iftowinghookisfixedonthesubframe,itshouldcontainsubframemodel.ThecuttingmodelasfollowFig2andFig3图2前拖钩有限元模型Fig2FrontHookFEA图3后拖钩有限元模型Fig3RearHookFEA白车身模型截取方法如下：前拖钩分析时截取车身前部，从前车门铰链安装轴线向后350mm处截取，如图4左图所示；后拖钩分析时截取车身后部，按照图4右图所示尺寸截取。ThemethodofcuttingBIWmodelasfollow:Forfronttowinghookanalysismodel,cuttingthe350mmdistancefromthehingeaxisoffrontdoortobackward,retainingthefrontpart.Seethefigure4.Forreartowinghookanalysismodel,cuttingthe350mmdistancefromthecornerofrearwheelcovertoforward,retainingthebackpart.Seethefigure4.图4车身截取模型Fig4CuttingBodyModel坐标系CoordinateSystems整车坐标系Globalcoordinatesystem建模技巧ModelingTechniques拖钩与螺纹管之间的连接采用TIE方式连接；车身焊点采用Fastener类型，CONN3D2单元，BEAM属性；车身焊缝单元采用壳单元进行模拟。在拖钩加载过程中容易出现穿透和干涉的地方增加接触。网格质量要求，翘曲小于12°，雅克比大于0.6，局部应力区域没有三角形单元，关键安装点周围没有三角形单元，模型三角形单元数量小于10%，拖钩及其连接区域单元细化。Thelinkbetweentowinghookandscrewedpipeadoptstietype.Thebodyspotadoptsfastenertype,CONN3D2elementandbeamproperty.Thebodyweldusesshellelementtosimulate.Besides,duringtheloadingforceonthetowinghook,themodeladdscontactpairstothewhereeasytopenetrateandinterference.Meshqualityrequirements,Warpage<12,Jacobin>0.6,Notrianglesinlocalstressarea,notriangularelementsaroundkeyfixpoints,Triangleselement<10%,Towinghookandlinkingareasmeshrefine.假设和限制Assumptions/Limitations假设Assumptions与物理试验相比较，对于焊点焊缝失效和钣金局部撕裂的地方，分析模型假设没有焊点焊缝失效和钣金撕裂。对于拖钩螺纹连接处，假设分析模型没有螺纹失效。Incomparisonwiththephysicaltest,wherespotweldsmailfailandmaterialmaylocallytear,theanalyticalmodelassumesnoweldsfailureandnomaterialtear.Tothescrewingconnectionoftowinghook,theanalyticalmodelassumesnoscrewingfailure.限制Limitations材料非线性属性被赋予拖钩和白车身模型。NonlinearmaterialpropertiesareassignedtothetowinghookandBIWparts.载荷和边界条件Loads/BoundaryConditions约束Constrain前拖钩：约束车身截面节点123DOF，前减震支柱安装点123DOF；后拖钩：约束车身截面节点123DOF，后减震弹簧支座123DOF；Fronttowinghook:CuttingsectionnodesDOF123,frontshocktowerSPCDOF123Reartowinghook:CuttingsectionnodesDOF123,rearspringseatSPCDOF123载荷Load表1工况描述Table1CaseDescription工况Case载荷Load方向Direction工况Case载荷Load方向Direction1F1水平拉伸，卸载Horizontalpull,unloading6F6向左25°压缩，卸载25°leftpush，unloading2F2水平压缩，卸载Horizontalpush,unloading7F7向上5°拉伸，卸载5°uppull，unloading3F3向左25°拉伸，卸载25°leftpull，unloading8F8向下5°压缩，卸载5°downpush，unloading4F4向右25°压缩，卸载25°rightpush，unloading9F9向下5°拉伸，卸载5°downpull，unloading5F5向右25°拉伸，卸载25°rightpull，unloading10F10向上5°压缩，卸载5°uppush，unloading注：F1=F2=F3=F4=F5=F6=F7=F8=F9=F10=0.5*整车满载质量*gF1=F2=F3=F4=F5=F6=F7=F8=F9=F10=0.5*grossvehicleweight*g图5前拖钩约束与载荷Fig5FrontTowingHookSPC&Load图6后拖钩约束与载荷Fig6RearTowingHookSPC&Load结果Results在odb结果文件中输出位移，应力和塑性应变Outputdisplacement,stressandplasticstraininodbresultfile性能要求PerformanceRequirements拖钩及其周围车身部件最大应力小于材料抗拉极限，最大塑性应变小于5%；车身上残余位移小于5mmMaxstressoftowhookandaroundbodypartlessthanmaterialUTS,Maxpla