Q/SZJ191001-2017后保險杠（系統(tǒng)）模態(tài)分析規(guī)范SpecificationOfModeAnalysisForRearFascia(Component)20XX20XX-09-30實施20XX-08-28發(fā)布XXXX汽車工程技術有限公司發(fā)布Q/SZXX-X-2017后保險杠（系統(tǒng)）模態(tài)分析規(guī)范范圍本標準規(guī)定了后保險杠（系統(tǒng)）模態(tài)分析方法及結果處理方法。本標準適用于CAE部門后保險杠（系統(tǒng)）模態(tài)分析。規(guī)范性引用文件無。術語和定義無。摘要ABSTRACT本分析規(guī)范的目的是為了確定后保險杠系統(tǒng)及其附件(霧燈)的第一階模態(tài)。Thepurposeofthisanalysisistodeterminethefirstnaturalfrequencyoftherearfasciaassemblyandfoglampinthevehicle.流程圖ProcessFlowDiagram建模建模Model1stmode>28Hz確定安裝點fixedpoint約束邊界Boundary設置參數(shù)計算Setparameter結束End優(yōu)化Optimization圖1流程圖Fig1ProcessFlowDiagram工具描述ToolDescription仿真分析過程中需要用到的如下軟件:Thefollowingsoftwarefacilitatestheanalyticalsimulationprocess:前處理(Preprocessors):Hypermesh求解器(AnalysisCode):MSC.Nastran后處理(Postprocessors):Hyperview建模和分析過程Modeling/AnalysisProcedure單位Units分析中所用單位制如下所示:Theunitsusedintheanalysisareasfollows:力(Force) 牛頓(N)質量(Mass) 噸(Ton)長度(Length) 毫米(mm)時間(Time) 秒(Second)內容Contents無坐標系CoordinateSystems整車全局坐標系。Vehicleglobalcoordinatesystem.建模技巧ModelingTechniques后保險杠系統(tǒng)和車身之間的零部件用RBE2約束1-3DOF，霧燈可以用集中質量代替Thecomponentsareattachedbyrigidconnections(RBE21-3)betweenrigidvehiclebodyandrearfasciaassembly.It’slefttouserdiscretiontoincludewhatcomponentsintothemodelbesidestherearfasciaassembly.Forfoglamps,includearepresentativehosingwithfoglampmass.假設和限制Assumptions/Limitations無載荷和邊界條件Loads/BoundaryConditions約束Constrains：約束后保險杠與車身連接點，約束1-6DOFOneapproachistouserearfasciaassemblyonly.Theboundaryconstraintsaredefinedattheattachmentbetweenrigidvehiclebodyandrearfasciaassembly.TheconstraintsinallDOFtotheassumedrigidvehiclebody.加載Loads：無圖2邊界約束Fig2Boundarycondition結果Results無性能要求PerformanceRequirements后保險杠一階模態(tài)大于28Hz，霧燈局部模態(tài)大于29Hz，以上模態(tài)值大于整車目標要求的1.1倍。1stFasciaresonantfrequency>28Hz,1stFasciaintegratedfoglampresonantfrequency>29Hz,AboveFrequencyvaluesareabout110%ofinvehicleAnalysistargets.分析要求ANALYSISREQUIREMENTS列出后保險杠的呼吸，彎曲，扭轉模態(tài)表，霧燈的模態(tài)。ModemapofNaturalResonantFrequency