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中英文翻译在全接触条件下盘式制动器摩擦激发瞬态热弹性不稳定的研究.doc

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中英文翻译在全接触条件下盘式制动器摩擦激发瞬态热弹性不稳定的研究.doc

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CIR2PI/L,WHERENISTHENUMBEROFHOTSPOTSONTHECIRCUMFERENCEOFTHEDISCCIRANDLISWAVELENGTHOFPERTURBATIONSTHESYMBOLST0MANDP0MINTHEABOVEFORMULAEDENOTETHEAMPLITUDESOFINITIALNONUNIFORMITIESEGFLUCTUATIONSBOTHPERTURBATIONS2AND3WILLBESEARCHEDASCOMPLEXFUNCTIONSTHEIRREALPARTDESCRIBINGTHEACTUALPERTURBATIONOFTEMPERATUREORPRESSUREFIELDOBVIOUSLY,IFTHEGROWTHRATEB0,THEINITIALFLUCTUATIONSAREDAMPEDONTHEOTHERHAND,INSTABILITYDEVELOPSIFB〉021TEMPERATUREFIELDPERTURBATIONHEATFLUXINTHEDIRECTIONOFTHEXAXISISZEROWHENTHERIBBEDPORTIONOFTHEDISCISCONSIDEREDNEXT,LETUSDENOTEKIKI/QICPICOEFFICIENTOFTHELAYERITEMPERATUREDIFFUSIONPARAMETERSKI,QI,CPIARE,RESPECTIVELY,THETHERMALCONDUCTIVITY,DENSITYANDSPECIFICHEATOFTHEMATERIALFORI1,2THEYHAVEBEENRECALCULATEDTOTHEENTIREVOLUMEOFTHELAYERI3WHENTHERIBBEDPORTIONOFTHEDISCISCONSIDEREDTHEPERTURBATIONOFTHETEMPERATUREFIELDISTHESOLUTIONOFTHEEQUATIONSWITHANDITWILLMEETTHEFOLLOWINGCONDITIONS1,THELAYERS1AND2WILLHAVETHESAMETEMPERATUREATTHECONTACTSURFACE2,THELAYERS2AND3WILLREACHTHESAMETEMPERATUREANDTHESAMEHEATFLUXINTHEDIRECTIONY,3,ANTISYMMETRICCONDITIONATTHEMIDPLANETHEPERTURBATIONSWILLBEZEROATTHEEXTERNALSURFACEOFAFRICTIONPADIF,INSTEAD,ZEROHEATFLUXTHROUGHEXTERNALSURFACEHASBEENSPECIFIED,WEOBTAINPRACTICALLYIDENTICALNUMERICALSOLUTIONFORCURRENTPADSIFWEWRITETHETEMPERATUREDEVELOPMENTININDIVIDUALLAYERSINASUITABLEFORMWEOBTAINWHEREAND22THERMOELASTICSTRESSESANDDISPLACEMENTSFORTHESAKEOFSIMPLICITY,LETUSCONSIDERTHERIBBEDPORTIONOFTHEDISCTOBEISOTROPICENVIRONMENTWITHCORRECTEDMODULUSOFELASTICITYTHOUGH,ACTUALLY,THESTIFFNESSOFTHISLAYERINTHEDIRECTIONXDIFFERSFROMTHATINTHEDIRECTIONYSUCHSIMPLIFICATIONIS,HOWEVER,ADMISSIBLEASTHEYIELDINGCENTRALLAYER3PRACTICALLYDOESNOTTAKEEFFECTONTHEDISCFLEXURALRIGIDITYUNLIKEFULLSIDEWALLSLAYER2GIVENATHERMALFIELDPERTURBATION,WECANEXPRESSTHESTRESSSTATEANDDISPLACEMENTSCAUSEDBYTHISPERTURBATIONFORANYLAYERTHETHERMOELASTICPROBLEMCANBESOLVEDBYSUPERIMPOSINGAPARTICULARSOLUTIONONTHEGENERALISOTHERMALSOLUTIONWELOOKFOR

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