外文资料--Thermal analysis of locomotive wheel-mounted brake disc.pdf外文资料--Thermal analysis of locomotive wheel-mounted brake disc.pdf

收藏 分享

资源预览需要最新版本的Flash Player支持。
您尚未安装或版本过低,建议您

IRANC2112012ELSEVIERLTDALLRIGHTSRESERVEDAPPLYINGANDLESSSUSCEPTIBLETOBRAKEFADE,WHICHLARGELYCONTRIBUTEDTOTHEIRPOPULARITY1THETHERMALANALYSISOFBRAKEDISCSISAPRIMARYSTAGEINTHESTUDYOFTHEBRAKESYSTEMS;BECAUSETHETEMPERATUREDETERMINESTHERMOMECHANICALBEHAVIOROFTHESTRUCTUREINTHEBRAKINGSURFACE,HIGHTEMPERATURESANDTHERMALGRADIENTSAREPRODUCEDTHISGENERATESSTRESSANDDEFORMATIONSINXSTRUCTUREOFEINTHELOCALHEATTRANSFERCOEFfiCIENTDISTRIBUTIONTHEREFORE,ASSUMINGACONSTANTVALUEFORHEATTRANSFERCOEFfiCIENTDOESNOTSEEMTOBELOGICALINTHISPAPER,THERMALANALYSISOFTHEWHEELMOUNTEDBRAKEDISCR920KFORTHEER24PCLOCOMOTIVEWHICHISMANUFACTUREDINMAPNALOCOMOTIVEENGINEERINGANDMANUFACTURINGCOMPANYMLCINCOOPERATIONWITHSIEMENSAGISINVESTIGATEDDRIVINGFORCEOFER24PCLOCOISSUPPLIEDUSINGADIESELELECTRICENGINEWITHTHEMAXIMUMSPEEDOF160KM/HTHISLOCOMOTIVEISUSEDTOPULLTHEPASSENGERWAGONSFORCALCULATINGTHEHEATTRANSFERCOEFfiCIENT,CORRESPONDINGAUTHORTEL989197481360;FAX982188013029CONTENTSLISTSAVAILABLEATAPPLIEDTHERMALENGINEERING512013948E952EMAILADDRESSBEHNAMGHADIMIUTACIRBGHADIMIBRAKESINMANYDIFFERENTTYPESOFVEHICLESSEVERALADVANTAGESOFBRAKEDISCSOVERSHOESBRAKESAREREPORTED,INCLUDINGBETTERSTOPPINGPERFORMANCEDISCCOOLEDREADILY,EASYTOCONTROLNOTSELFCALCULATIONSINBRAKEDISCS5,12,13ASITISREPORTEDINTHEEXPERIMENTALRESULTS,COMPLETHEVENTILATEDTYPEBRAKEDISCCAUSESAGREATCHANGASTHESPEEDRESTRICTIONOFTRAINSCONTINUESTOEXPAND,OVERHEATINGANDTHERMALDEFORMATIONONBRAKESYSTEMSAREGOINGTOBECRITICALFOREMERGENCYBRAKINGEVENIFDYNAMICBRAKINGSYSTEMSAREUSEDINNORMALSERVICEBRAKING,THEIRPERFORMANCESARENOTSUFfiCIENTTOENSUREANEMERGENCYBRAKINGATHIGHSPEEDSOFRICTIONBRAKINGSYSTEMSHAVECRUCIALROLEINEMERGENCYBRAKINGFORSEVERALYEARS,BRAKEDISCSINCREASINGLYBECAMEMOREPOPULARTHANSHOESTRANSFERONTHETOTALAMOUNTOFDISSIPATEDENERGYTOTHESURROUNDISINSIGNIfiCANT3E7,ANDCONDUCTIONANDCONVECTIONMODESOFHEATTRANSFERPLAYACRUCIALROLEINCONTRIBUTIONOFHEATEXCHANGEOFTHEBRAKESYSTEMTHEPROBLEMOFTHEflUIDflOWBETWEENTHEfiNSOFTHEVENTILATEDTYPEOFBRAKEDISCSISOFTENANALYZEDININDIVIDUALSTUDIESBASEDONTHECFDMETHOD8E11NEVERTHELESSOFTENANAVERAGE,CONSTANTVALUEOFTHEHEATTRANSFERCOEFfiCIENTISUSEDATTEMPERATURE1INTRODUCTIONWHICHTHECONSEQUENCESAREMANIFESTEDBYTHEAPPEARANCEOFCRACKS2DURINGTHENORMALBRAKING,INflUENCEOFTHERADIATIONHEATARTICLEINFOARTICLEHISTORYRECEIVED17SEPTEMBER2012ACCEPTED29OCTOBER2012AVAILABLEONLINE7NOVEMBER2012KEYWORDSWHEELMOUNTEDBRAKEDISCPADHEATTRANSFERLOCOMOTIVE13594311/ESEEFRONTMATTERC2112012ELSEVIERLTDHTTP//DXDOIORG/101016/JAPPLTHERMALENG20121005ABSTRACTINRECENTDECADESTHEIMPROVEMENTOFTHEBRAKINGPERFORMANCESAREREQUIREDDUETOHIGHSPEEDOFTRAINSTHEGENERATEDFRICTIONALHEAT,DURINGBRAKINGOPERATIONCAUSESSEVERALNEGATIVEEFFECTSONTHEBRAKESYSTEMSUCHASBRAKEFADE,PREMATUREWEAR,THERMALCRACKSANDDISCTHICKNESSVARIATIONITISTHENIMPORTANTTODETERMINETHETEMPERATUREfiELDOFTHEBRAKEDISCINTHEPRESENTWORK,THERMALANALYSISOFTHEWHEELMOUNTEDBRAKEDISCR920KFORTHEER24PCLOCOMOTIVEISINVESTIGATEDTHEBRAKEDISCANDflUIDZONEARESIMULATEDASA3DMODELWITHATHERMALCOUPLINGBOUNDARYCONDITIONTHEBRAKINGPROCESSISSIMULATEDINLABORATORYANDTHEEXPERIMENTALDATAAREUSEDTOVERIFYTHESIMULATIONRESULTSDURINGTHEBRAKING,THEMAXIMUMTEMPERATUREWASOBSERVEDINTHEMIDDLEOFBRAKINGPROCESSINSTEADOFTHEBRAKINGENDPOINTMOREOVER,ALARGELAGGINGWASOBSERVEDFORfiNSTEMPERATUREWHICHRENDERSNOCOOLINGATTHEBEGINNINGOFTHEBRAKINGDISCSURFACETEMPERATURESINCREASEDBRAKINGTIME,ANDTHENDECREASEDLAGGINGEFFECTRENDERSNOCOOLINGATTHEBEGINNINGOFTHEBRAKINGWITHINCREASINGTHERMALANALYSISOFLOCOMOTIVEWHEELMOUNTEDBGHADIMIA,,FKOWSARYA,MKHORAMIBASCHOOLOFMECHANICALENGINEERING,COLLEGEOFENGINEERING,UNIVERSITYOFTEHRAN,TEHRAN,BMECHANICALENGINEERINGDEPARTMENT,MAPNALOCOMOTIVECOMPANY,KARAJ,IRANHIGHLIGHTSATEACHTIMESTEPTHELOCALHTCWASCALCULATED,ANDUSEDFORDISCTHERMALNUMERICALRESULTSCOMPAREWELLWITHEXPERIMENTALDATAAPPLIEDTHERMALJOURNALHOMEPAGEWWWELSEVIALLRIGHTSRESERVED1BRAKEDISCANALYSISSCIVERSESCIENCEDIRECTENGINEERINGERCOM/LOCATE/APTHERMENGPARTSIFTHELOCOMOTIVESTOPSCOMPLETELYV2U20THENALLTHEROTATINGPARTSWILLBEEXPRESSEDRELATIVETOTHEREVOLUTIONSOFTHEWHEELEQ1CANBEREWRITTENASFOLLOWSEB12M1IR2WMV2112KCFMV212flYWHEELMASSESANDASSEMBLYOFLOCOWHEELLENGINEERING512013948E952949THEflUIDflOWWITHINTHECHANNELWASMODELEDUSINGTHEFLUENTCFDSOFTWAREATEACHTIMESTEP,DUETOTHELOCOMOTIVESPEEDANDTEMPERATUREDISTRIBUTIONINTHEBRAKEDISC,THELOCALHEATTRANSFERCOEFfiCIENTOFfiNSWASCALCULATEDANDWASAPPLIEDASABOUNDARYCONDITIONFORTHEBRAKEDISCTHERMALANALYSISANEXPERIMENTALDATAVERIfiEDTHEMODELINGRESULTS2EXPERIMENTALSETUPARAILWAYBRAKEDISCSYSTEMISTESTEDONTHEZFDYNAMOMETERFIG1INTHEFAIVELEYTRANSPORTCOMPANYANDRESULTSWEREREPORTEDTOMLC14ZFDYNAMOMETERISABLETORUNWITHSPECIfiCMISSIONPROfiLESINDRYANDWETCONDITIONSTHEDYNAMOMETERHASANELECTRICMOTOROF536KWANDUPTOFOURCOUPLEABLEflYWHEELMASSESTOSIMULATEVARIOUSWEIGHTSANDLOADSOFVEHICLESTHEMEASUREMENTOFTEMPERATUREISAVERYIMPORTANTSTEPINTHETESTPROCEDUREFORTHISPURPOSE,AKTYPETHERMOCOUPLEIN15MMTHICKNESSWASUSEDFORMODELINGTHEBRAKINGPHENOMENA,LOCOMOTIVEWHEELWASACCELERATEDWITHTHECONSTANTVALUEOF08M/S2ANDREACHEDTOTHEDESIREDVELOCITY,THENTHEBRAKINGSTARTEDANDCAUSEDCONSTANTDECELERATIONWITHTHERATEOF1117M/S2DURINGTHEBRAKING,BRAKINGSURFACEANDfiNSWALLTEMPERATURESWERERECORDEDANDUSEDFORVALIDATINGTHENUMERICALRESULTS3MODELINGTHEER24PCLOCOMOTIVECONSISTSOFTWOBOGIESEACHBOGIEHASFOURWHEELSWITHONESETOFWHEELMOUNTEDBRAKEDISCSWHICHCONSISTSOFTWOBRAKEDISCSARRANGEDONBOTHSIDESOFAWHEELANDAREBOLTEDTOGETHERTHROUGHTHEWHEELWEBFIG231THERMALMODELINGREGARDINGTOTHEUNIFORMPRESSUREORTHECONSTANTWEARFIG1ZFDYNAMOMETERWITHCOUPLEABLEBGHADIMIETAL/APPLIEDTHERMABOUNDARYCONDITIONATTHECONTACTSURFACE,TWOMETHODSAREAVAILABLEFORCALCULATINGTHEBRAKINGHEATGENERATIONRATEUNIFORMPRESSUREDISTRIBUTIONINTHECONTACTREGIONISOFTENVALIDWHENTHEPADISNEWHOWEVERAFTERBRAKINGFORSEVERALTIMES,ASSUMPTIONOFUNIFORMWEARISMOREPRAGMATICINTHISSTUDY,THEPADWASUSEDSEVERALTIMESANDUNIFORMWEARBETWEENPADANDBRAKEDISCISSTABILIZED,HENCETHEHEATflUXISJUSTAFUNCTIONOFTIMEANDITISINDEPENDENCEOFTHESPATIALVARIABLES5FORAVEHICLEWHICHISDECELERATINGONALEVELSURFACEFROMAHIGHERVELOCITYV1TOALOWERVELOCITYV2THEBRAKINGENERGYEBCANBEWRITTENASEB12MC16V21C0V22C1712IC16U21C0U22C171WHEREIISRELATEDTOTHEMASSMOMENTOFINERTIAOFTHEROTATINGPARTS,MLOCOMOTIVEMASSANDUISTHEANGULARVELOCITYOFROTATINGFIG2AWHEELMOUNTEDBRAKEDISC,BWHEELMOUNTEDBRAKEDISCR920K,SET,MOUNTEDWHERELISTHEHEATGENERATIONRATIO,Q00DANDQ00PARETHEHEATflUXABSORBEDBYTHEBRAKEDISC,ANDPAD,RREPRESENTSDENSITY,CISTHESPECIfiCHEAT,KTHETHERMALCONDUCTIVITYANDTHEINDEXDANDPINDICATEDISCANDPAD,RESPECTIVELYUSINGEQ4AND5,THEHEATTABLE1BRAKEDISCR920KDATABRAKINGMASSPERBRAKEDISCKG54565WHEELDIAMETERORIGINMM1100BRAKEDISCOUTERDIAMETERMM920BRAKEDISCINNERDIAMETERMM640WIDTHOFRINGMM24WIDTHOFfiNSMM30DENSITYOFBRAKEDISCMATERIALKG/M37246SPECIfiCHEATOFBRAKEDISCMATERIALJ/KGK500THERMALCONDUCTIVITYOFBRAKEDISCMATERIALW/MK58DENSITYOFBRAKEPADKG/M32180SPECIfiCHEATOFBRAKEPADJ/KGK1090THERMALCONDUCTIVITYOFBRAKEPADW/MK167AVERAGEFRICTIONCOEFfiCIENTM032AMBIENTTEMPERATUREC14C55STARTTEMPERATUREOFBRAKEDISCC14C55DECELERATIONOFVEHICLEAVERAGEM/S21177ENGINEERING512013948E952BGHADIMIETAL/APPLIEDTHERMAL950WHEREKCFISTHECORRECTIONFACTORFORROTATINGMASSESANDRWISTHEWHEELRADIUSBRAKINGPOWERPBISEQUALTOBRAKINGENERGYDIVIDEDBYTHEBRAKINGTIMET,ORPBDEBDT3FORCONSTANTDECELERATION,EQ2ANDEQ3YIELDTHEBRAKEPOWERASPBKCFMAV1C0AT4WHEREAISTHEDECELERATIONOFTHELOCOMOTIVETHEDISTRIBUTIONOFBRAKINGENERGYBETWEENPADANDDISCCANNOTBEPREDICTEDREADILYGENERALLY,THERMALCONDUCTIVITYOFTHEBRAKEPADSISSMALLERTHANTHEDISCKPKD,SOONECANCONSIDERTHATTHETOTALAMOUNTOFTHEBRAKINGHEATWILLBECOMPLETELYABSORBEDBYTHEBRAKEDISCTHISASSUMPTIONLEADSTOHIGHERTEMPERATUREESTIMATIONFORBRAKEDISCTOAVOIDTHISISSUE,SUPPOSETHATTHEBRAKINGOPERATIONTIMEISSHORT,HENCETHEPADANDBRAKECANBECONSIDEREDASSEMIINfiNITESOLIDSANDTHEHEATGENERATIONRATIOCANBECALCULATEDASFOLLOWS15LQ00DQ00PRDCDKDRPCPKP125FIG3MESHCONSTRUCTION,ABRAKEDISC,BflUIDREGIONflUXONTHEBRAKINGSURFACECANBEFOUNDQ00DLAL1KCFMAV1C0AT6WHEREAISTHEDISCANDPADCONTACTAREA32MODELINGANDBOUNDARYCONDITIONSFORFEMANDCFDANALYSIS,THREEDIMENSIONAL3DCONSTRUCTIONSOFBRAKEDISCANDCOOLINGAIRDOMAINWEREMODELEDFIG3FORSOLVINGTHECONTINUITY,MOMENTUMANDENERGYEQUATIONS,FLUENTUNSTEADYSOLVERWASUSEDWITHSIMPLEALGORITHMFORPRESSUREANDVELOCITYCOUPLINGANDKC0ΕREALIZABLEMODELFORVISCOUSflOWMODELINGPHYSICALPROPERTIESOFBRAKEDISCANDBOUNDARYCONDITIONSFORANALYSISAREGIVENINTABLE1HEATflUXINTHEBRAKINGSURFACEISCALCULATEDFROMEQ6ATEACHTIMESTEP,ACCORDINGTOTHELOCOMOTIVESPEEDANDDISTRIBUTIONOFTEMPERATUREINTHEBRAKEDISC,THEFIG4THERMALSIMULATIONOFBRAKEDISCR920K,ONESTOPSFROM154KM/HLENGINEERING512013948E952951BGHADIMIETAL/APPLIEDTHERMALOCALHEATTRANSFERCOEFfiCIENTOFfiNSISCALCULATEDBYSOLVINGTHERANSANDENERGYEQUATIONSINTHEflUIDZONE,ANDUSEDASABOUNDARYCONDITIONFORTHEBRAKEDISCTHERMALANALYSISTHENTHEENERGYEQUATIONWASSOLVEDINTHEBRAKEDISCANDTEMPERATUREDISTRIBUTIONATTHESUBSEQUENTTIMESTEPWASCALCULATEDTHISPROCEDURECONTINUESUNTILTHELOCOMOTIVECAMETOASTOP4RESULTSANDDISCUSSIONTHETHERMALANALYSISOFWHEELMOUNTEDBRAKEDISCOFMAPNALOCOER24PCWASCONDUCTED,INTHECASEOFONEEMERGENCYSTOPFROM154KM/HFIG4SHOWSNUMERICALRESULTSINGOODCOMPARISONWITHEXPERIMENTALDATAFROMTHISfiGURE,ITISSEENTHATTHEDISCSURFACETEMPERATUREWILLINCREASEWITHINCREASINGBRAKINGTIMEANDTHENITDECREASESDUETOASIGNIfiCANTREDUCTIONINHEATGENERATIONVALUEOVERTHEBRAKESURFACEDUETOTHEHEATCONDUCTIONEFFECTS,ITISPOSSIBLETOSEEALARGEDELAYORTIMELAGINfiNSTEMPERATURETHISLAGGINGEFFECTRENDERSNOCOOLINGATTHEBEGINNINGOFTHEBRAKING,SOTHESURFACETEMPERATUREWILLINCREASESHARPLYAFTERAFEWSECONDS,THEHEATflUXAFFECTSTHEfiNSANDfiNSTEMPERATUREINCREASESBYCONVECTIONCOOLINGOFTHEfiNS,BRAKINGHEATDISSIPATESTOTHEAIR,ANDTHERATEOFINCREASINGINSURFACETEMPERATUREWILLBEREDUCEDTEMPERATUREDISTRIBUTIONONTHEBRAKEDISCINTHREEDIFFERENTTIMESISPRESENTEDINFIG5DUETONONUNIFORMCOOLINGOFTHEfiNSINTHEIRLENGTH,THEMAXIMUMTEMPERATUREWASOBSERVEDINTHEDIFFERENTREGIONSINTHEDIFFERENTTIMESFROMFIG5ITISOBVIOUSTHATTHETEMPERATUREVALUEATTHETOPOFTHEfiNSISGREATERTHANTHETEMPERATUREVALUEBETWEENTHEfiNSTOELABORATETHISBEHAVIOR,THEDISTRIBUTIONOFVELOCITYVECTORATT205SISPRESENTEDINFIG6LINEARANDROTATIONALVELOCITYEFFECTSFIG5TEMPERATUREDISTRIBUTIONSOFTHEONTHEAIRflOWTHROUGHTHEDISCARECLEARLYVISIBLEINTHISfiGURESTAGNATIONANDWAKEREGIONREGIONAATTHETOPOFTHEfiNS,ANDHIGHAIRVELOCITYABOUT22M/SCANBESEENBETWEENTHEfiNSREGIONBSTAGNATIONREGIONCAUSEDLOWLOCALHEATTRANSFERC
编号:201311071000213302    类型:共享资源    大小:1.43MB    格式:PDF    上传时间:2013-11-07
  
1
关 键 词:
外文资料 外文翻译
  人人文库网所有资源均是用户自行上传分享,仅供网友学习交流,未经上传用户书面授权,请勿作他用。
关于本文
本文标题:外文资料--Thermal analysis of locomotive wheel-mounted brake disc.pdf
链接地址:http://www.renrendoc.com/p-93302.html
关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服客服 - 联系我们

网站客服QQ:2846424093    人人文库上传用户QQ群:460291265   

[email protected] 2016-2018  renrendoc.com 网站版权所有   南天在线技术支持

经营许可证编号:苏ICP备12009002号-5