Q/SZJ191001-2017副車(chē)架和橫梁模態(tài)性能評(píng)估PerformanceAssessmentofCradlesorCrossMemberModes20XX20XX-12-31實(shí)施20XX-11-27發(fā)布XXXX汽車(chē)工程技術(shù)有限公司發(fā)布Q/SZXX-X-2017副車(chē)架和橫梁模態(tài)性能評(píng)估范圍本標(biāo)準(zhǔn)規(guī)定了術(shù)語(yǔ)和定義、副車(chē)架和橫梁模態(tài)分析方法及結(jié)果處理方法。本標(biāo)準(zhǔn)適用于CAE部門(mén)的副車(chē)架和橫梁模態(tài)分析。規(guī)范性引用文件無(wú)。術(shù)語(yǔ)和定義無(wú)。摘要Abstract評(píng)價(jià)副車(chē)架和橫梁的模態(tài)性能。Assessthemodalperformanceofavehiclecradleorcrossmember.流程圖ProcessFlowDiagram檢查模型檢查模型CheckModel設(shè)置邊界設(shè)置邊界及載荷SettheboundaryConstraintsandloads提交提交計(jì)算RunNastranSOL103模態(tài)評(píng)估模態(tài)評(píng)估ModesAssess圖1流程圖Fig1ProcessFlowDiagram工具描述ToolDescription仿真分析過(guò)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(guò)程Modeling/AnalysisProcedure所有的模型必須符合NVH建模標(biāo)準(zhǔn)，以及符合噪聲和振動(dòng)分析的建模文檔。AllmodelsmustconformtotheNVHmodelingstandardsasoutlinedaswellastheindividualcomponentmodelingdocumentsasapprovedbytheNoiseandVibrationFocusGroup.單位Units分析中所用單位制如下所示:Theunitsusedintheanalysisareasfollows:力(Force) 牛頓(N)質(zhì)量(Mass) 噸(Ton)長(zhǎng)度(Length) 毫米(mm)時(shí)間(Time) 秒(Second)內(nèi)容Contents對(duì)于這個(gè)案例,下面的子系統(tǒng)必須包含在指定的建模技術(shù)中。包含前副車(chē)架，后副車(chē)架，橫梁。簡(jiǎn)化和詳細(xì)的建模技術(shù)都是允許的，標(biāo)準(zhǔn)是使用詳細(xì)的建模技術(shù)，除非信息不能用于構(gòu)建詳細(xì)的模型。Forthisloadcase,thesubsystemsbelowmustbeincludedwiththespecifiedmodelingtechniques.IncludeFrontCradle,RearCradle,cross.Whenbothsimplifiedanddetailedmodelingtechniquesareallowed,thestandardistousethedetailedmodelingtechniqueunlessinformationisnotavailablefortheconstructionofadetailedmodel.坐標(biāo)系CoordinateSystems整車(chē)坐標(biāo)系。Globalcoordinatesystem.建模技巧ModelingTechniques無(wú)。假設(shè)和限制Assumptions/Limitations無(wú)。載荷和邊界條件Loads/BoundaryConditions約束：副車(chē)架和橫梁無(wú)約束為自由狀態(tài)。Thecradleandcrossistobeassessedinafree-freestate.加載：正則化模態(tài)分析。Loads：normalmodesanalysis.結(jié)果Results模態(tài)結(jié)果是頻率的分析報(bào)告（Hz）。應(yīng)該有六個(gè)剛體模態(tài)，模型應(yīng)通過(guò)所有建模檢查。Themodalresultsshouldbereportedincycles/sec(Hz).Thereshouldbeexactly6rigidbodymodesandthemodelshouldpassallmodelingchecks.性能要求PerformanceRequirements符合NVH底盤(pán)部件結(jié)構(gòu)性能要求。AsprescribedintheN&V“ChassisCradle/CrossMemberStructuralModes”verbiageinthecradle“StatementofRequirements”(SOR).分析要求ANALYSISREQUIREMENTS副車(chē)架和橫梁的一個(gè)特征值求解，所有的模態(tài)都應(yīng)該在性能要求的規(guī)定下提取。AnEigenvaluesolutionshouldbeperformedonthecradleandallmodesshouldbeextractedbelowwhatisspecifiedbytheperformancerequirements.魯棒性分析信息RobustAnalysisInformation對(duì)于魯棒分析的一般描述，請(qǐng)參閱NVH有限元分析的魯棒性分析，下面列出了噪聲因素，控制因素和約束條件如下所示，關(guān)于噪聲和控制因素的一般性建議，請(qǐng)參閱適用的的NVH知識(shí)集。Forageneraldescriptionsofrobustanalysis,pleaserefertotheN&VFiniteElementModelRobustAnalysis.Noisefactors,controlfactors,andconstraintsarelistedbelow.Forgeneralrecommendationsonnoiseandcontrolfactors,pleaserefertotheapplicableNVHknowledgesets.噪音（雜音）因子（NoiseFactors）以下是副車(chē)架和橫梁模型的雜音因子：密度和彈性模量。密度和彈性模量是一個(gè)范圍值，基于圖紙規(guī)范。如果密度參數(shù)在求解中占主導(dǎo)因素的話，應(yīng)把他從噪音因子里去掉，其他雜音因子的限值應(yīng)由開(kāi)發(fā)團(tuán)隊(duì)共同商定。Thefollowingarethenoisefactorsforthecradlemodels:DensityandYoung’sModulus.UncertaintyboundsofdensityandYoung’sModulusshouldbebasedondrawingspecifications.Incasesweredensitydominatesthesolutionthanitshouldbetakenout.Allotherboundsshouldbeagreeduponbythedevelopmentteam.控制因子(ControlFactors)以下是副車(chē)架和橫梁模型的控制因子:零件厚度、單元尺寸和焊接。其他的邊界應(yīng)由團(tuán)隊(duì)共同決定。Thefollowingarethecontrolfactorsforthecradlemodels:Partthickness,elementsizeandwelding.Uncertaintyboundsshouldbeagreeduponbythedevelopmentteam.約束(Constraints)同以上噪聲和控制因子的詳細(xì)說(shuō)明類似。Thosedetailedinthenoiseandcontrolfactors.魯棒性分析原則(RobustAnalysisPrincipals)分析目標(biāo)是通過(guò)了解關(guān)鍵設(shè)計(jì)特征加上制造和分析變量來(lái)優(yōu)化副車(chē)架和橫梁模型及質(zhì)量。由于幾何優(yōu)化很困難，厚度、彈性模量和密度/附件質(zhì)量被作為設(shè)計(jì)更改的變量，而無(wú)需描述具體的設(shè)計(jì)變更。例如，如果厚度隨著優(yōu)化效果顯著提升，這就說(shuō)明需要在截面上進(jìn)行更改。Analysisgoalsaretooptimizeforcradlemodesandmassbyunderstandingthekeydesigncharacteristicsplusmanufacturingandanalyticalvariables.Becausegeometricoptimizationsaredifficulttoexecute,gagethickness,Young’smodulus,anddensity/trimmassareusedtounderstandwheredesignchangesareneeded,withoutspecificallydescribingwh