车辆工程汽车离合器的外文文献翻译

湖北文理学院毕业设计(论文)英文翻译题目有限元热分析的陶瓷离合器专业车辆工程班级Xxx姓名Xxxx学号2010138xx指导教师职称Xxx副教授2014年2月25日湖北文理学院毕业设计（论文）报告纸-1-Fethermalanalysisofaceramicclutch1.IntroductionAbrasivedryrunningvehicleclutchesareforceclosurecouplings.Torqueandspeedtransmissionareensuredbythefrictionalforcegeneratedbetweentwopressedsurfaces.Reasonsfortheapplicationofceramicasafrictionmediumincludegoodheatandwearresistanceproperties,whichprovidetheopportunitytodrivehigherpressures,andalowdensity.Thus,anincreasingpowerdensityisenabledwithaparallelminimizationofconstructionspace.MeasurementswithafirstprototypeofaclutchdiskusingceramicfacingswereperformedatKarlsruheUniversityinalaboratoryspecializedinpassengercardrivesystemtesting.Inthecourseofanalysisthefiniteelement(FE)modelwastobeconstructedwiththeknowledgeofmeasurementdataandmeasurementconditions.Calculationswereintendedtodeterminethetemperaturedistributionoftheclutchdiskanditsenvironmentateachmomentintimecorrespondingtomeasurements.Itisessentialtobefamiliarwiththetemperaturerangeinordertoexaminethewearcharacteristicsofthesystem.Thus,importantinformationisderivedfrommeasurementdata.Incriticalloadcases,thehighestexpectedtemperaturesmustbeforecastinspaceandtimeinordertoprotectmeasuringinstrumentsclosetothelocationofheatgeneration.Thegoalofthisstudyistoanalyzeandmodifytheclutchsystemtoprovidebetteroperatingconditionsbyimprovingtheheatconductionandconvectionofthesystemortoincreasetheamountoftheenergyconvertedintofrictionalheat.Furthermore,itisdesiredtofindbetterdesignsolutionsformoreefficientclutchsystems.CalculationswereperformedbytheCosmosDesignStarsoftware.Duringmodeldevelopment,greatcarehadtobetakenforpropersimplificationofgeometry,theselectionofelementsizes,andthecorrectadjustmentoftimestepsduetothesubstantialhardwarerequirementsfortransientcalculations.Changesinthermalparameterssuchasthesurfaceheatconvectioncoefficientandthermalloadhadtobetakenintoconsiderationonanon-goingbasisintermsoftimeandlocation.Thetwosidesoftheanalyzedtestclutchsystemcanonlybemanagedbytwoindependentmodelslinkedbyheatpartition,湖北文理学院毕业设计（论文）报告纸-2-accordingtothehypothesisthatthecontacttemperaturemustbeidenticalonbothsideswhilethereispropercontactbetweenthemanditsvaluemustbeadjustedbyiteration.Calculationsrevealedthattheheatpartitionchangedbycycleanditdifferedalongtheinnerandoutercontactrings.Asaresultofthedifferentcoolingcharacteristicsbetweentheceramicandsteelside,aheatflowislaunchedfromtheceramicsidetothesteelside.Thisheatflowwasalsodeterminedbyiteration,itsvaluealsochangesbycycleanddiffersalongtheinnerandoutercontactrings.2.FirstprototypeofaclutchusingengineeringceramicsasfrictionmaterialTheexaminedclutchdiskwasdevelopedaccordingtothe“specificceramic”productdevelopmentprocessestablishedattheInstituteforProductDevelopment(IPEK)attheUniversityofKarlsruhe.Thisdevelopmentprocessalreadyhasthepossibilityforconnectiontoarealtransmissionshaft;further,ithasacushionspringdeviceforthefacingsallowinggoodstartbehaviour.Abrasiveclutchesmustcomplywiththefollowingbasicrequirements:hightorquetransmissionaccordingtohighfrictioncoefficients,highcomfort(novibrationsthroughself-inducedchattering),homogeneoustemperaturedistribution,lowwearcharacteristic.Acriticalelementoftheswitchistheabrasivedisk.Withregardtothedesignutmostcaremustbetakentoselecttherightmaterial.Ahighandconstantfrictioncoefficient,，wearresistanceandthermalresistancearedesiredcharacteristics.Theclutchdiskhasinsteadofthegenerallyappliedring-shapedabrasiveinlettworowsofSSIC(assintered)ceramicpellets.Thesepelletsareplacedon6separatesegments.Thesegmentsarefixedtothecentralhubbyrivets.Eachsegmentconsistsof4plates,2workingasfacingspringsand2ascarriers.3.MeasurementsMeasurementswereperformedatthedepartmentofpowertraindevelopmentoftheInstituteforProductDevelopment(IPEK)attheKarlsruheUniversity(TH)Research湖北文理学院毕业设计（论文）报告纸-3-University,whereacategoryIVcomponenttestrigisusedfortestsofnewfrictionalmaterialsandexaminationsofnewmaterialsinrealclutchdisks.Realconditionsareappliedbythesimulationofdrivingresistance(e.g.startingintheplane,startingatthehill).Itisacomponenttestrigleveledonthefourthpositionofthetribologicaltestingenvironment.Inordertogiveanideaofdimensions:theequipmentlengthisabout4-5m.Thetwoelectricmotorsandtheaxialforcearecontrolledindependentlybycomputer;therebymanyoperationalstatescanberealized.Thisenablestheequipmenttocompleteamyriadoftribologicalmeasurementsallwhileproperlymodelingtheoperationofaclutchdiskinapassengercar.ItisalsoequippedwithanautomaticITmeasurementsystem.Measurablequantitiesincludethefollowing:twoheavy-dutyelectricmotors(150KW,BaumullerDS160L-305),devicesuitableforexertingaxialforce,torquemeter(MannerSensortelemetrieMF100),axialforcemeter,steeldiskinfriction,replaceableheadtoaffixthedevicetobetested,temperaturealongtwodifferentradiiat0.4mmbelowtheabrasivesurfaceofthesteeldisk(OmegaHJMTSS-IM100U-150-2000,J-typeiro-constantanthermocouples),revolutionsperminuteforbothsides(PolyteneLSV065).Thegreatestchallengeoutoftheseistemperaturemeasurementaswewould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