外文翻译-汽车散热器性能

毕业设计（论文）外文参考资料及译文译文题目：AutomotiveRadiatorPerformance汽车散热器性能学生姓名：学号：专业：所在学院：指导教师：职称：20xx年2月27日

AutomotiveRadiatorPerformanceAbstract—Automotiveenginecoolingsystemtakescareofexcessheatproducedduringengineoperation.Itregulatesenginesurfacetemperatureforengineoptimumefficiency.Recentadvancementinengineforpowerforcedenginecoolingsystemtodevelopnewstrategiestoimproveitsperformanceefficiency.Alsotoreducefuelconsumptionalongwithcontrollingengineemissiontomitigateenvironmentalpollutionnorms.Thispaperthrowslightonparameterswhichinfluenceradiatorperformancealongwithreviewssomeoftheconventionalandmodernapproachestoenhanceradiatorperformance.IndexTerms—Automotiveenginecoolingsystem,Performance,RadiatorI.INTRODUCTIONAutomotiveenginecoolingsystemtakescareofexcessheatproducedduringengineoperation.Itregulatesenginesurfacetemperatureforengineoptimumefficiency.Mostautomotiveenginecoolingsystemsconsistoftheradiator,waterpump,coolingfan,pressurecapandthermostat.Radiatoristheprimecomponentofthesystem.Radiatorisaheatexchangerthatremovesheatfromenginecoolantpassingthroughit.Heatistransferredfromhotcoolanttooutsideair.Radiatorassemblyconsistsofthreemainpartscore,inlettankandoutlettank.Corehastwosetsofpassage,asetoftubesandasetoffins.Coolantflowsthroughtubesandairflowsbetweenfins.Thehotcoolantsendsheatthroughtubestofins.Outsideairpassingbetweenfinspickupsandcarriesawayheat.ManuscriptreceivedFebruary,2013.PawanS.Amrutkar,DepartmentofMechanicalEngineering,SinhgadAcademyofEngineering,UniversityofPune,India.SangramR.Patil,DepartmentofMechanicalEngineering,SinhgadAcademyofEngineering,UniversityofPune,India.Performanceofenginecoolingsystemisinfluencedbyfactorslikeairandcoolantmassflowrate,airinlettemperature,coolantfluid,fintype,finpitch,tubetypeandtubepitchetc.Whiledesigningcoolingsystemthreeworstconditionsconsideredbasedonaboveparameters.Highaltitude:Athighaltitude,airdensitybecomeslowandhenceaffectsairmassflowrate.Summerconditions:Duringsummersurroundingairishoti.e.airinlettemperatureismore.Maximumpower:Engineconditionproducingmaximumpowerlikewhenvehicleisclimbinguphill,maximumheatrejectionisrequiredduringthiscondition.Tocompensateallthesefactorsradiatorcoresizerequiredmaybelarge.II.LITERATUREREVIEWC.Oliet,A.Oliva,J.Castro,C.D.studieddifferentfactorswhichinfluenceradiatorperformance.Itincludesairandcoolantflow,findensityandairinlettemperature.Itisobservedthatheattransferandperformanceofradiatorstronglyaffectedbyairandcoolantmassflowrate.Asairandcoolantflowincreasescoolingcapacityalsoincreases.Whenairinlettemperatureincreases,heattransferandthuscoolingcapacitydecreases.Smallerfinspacingandhigherlouverfinanglehavehigherheattransfer.Findensitycanbeincreasedtillitblockstheairflowandheattransferratedecreases.JPYadavandBharatRajSinghintheirstudiesalsopresentedparametricstudyonautomotiveradiator.Intheperformanceevaluation,aradiatorisinstalledintoatestsetup.Thevariousparametersincludingmassflowrateofcoolant,inletcoolanttemperature;etc.arevaried.Followingremarksareobservedduringstudy:Influenceofcoolantmassflowcoolingcapacityoftheradiatorhasdirectrelationwiththecoolantflowrate.Withanincreaseinthevalueofcoolingflowrate,thereiscorrespondingincreaseinthevalueoftheeffectivenessandcoolingcapacity.Influenceofcoolantinlettemperaturewiththeincreaseintheinlettemperatureofthecoolantthecoolingcapacityoftheradiatorincreases.MazenAl-Amayrehinhisstudy,testedthethermalconductivitiesofethyleneglycol+water,diethyleneglycol+waterandtriethyleneglycol+watermixtures,measuredattemperaturesrangingfrom25°Cto40°Candconcentrationsrangingfrom25wt.%glycolto75wt.%glycol.Increasingtheconcentrationofglycolleadstodecreaseofthermalconductivity.Increasingthetemperatureofmixtureresultedinslightincreaseinthermalconductivity.Thevarioustechniquesareusedtoenhancetheperformanceofautomotiveenginecoolingsystem.Itmaybeeitherconventionalormodernapproach.Conventionalapproachreliesonfin,tubeandfandesignoptimization.Moderntechniquesarebasedonnewtechnologieslikenano-technology,heatloadaveragingcapacityoractuatorbasedenginecoolingsystem.Thispaperreviewssomeoftheconventionalandmodernapproachesfocusingonradiatorperformanceenhancement.P.K.Trivedi,N.B.VasavaillustratedtheeffectofTubepitchforbestconfiguredradiatorforoptimumperformance.Heattransferincreasesasthesurfaceareaoftheradiatorassemblyisincreased.Thisleadstochangethegeometrybymodifyingthearrangementoftubesinautomobileradiatortoincreasethesurfaceareaforbetterheattransfer.ThemodificationinarrangementoftubesinradiatoriscarriedoutbystudyingtheeffectofpitchoftubebyCFDanalysisusingCFX.ResultsShowsthatasthepitchoftubeiseitherdecreasedorincreasedthanoptimumpitchoftubes,theheattransferratedecreases.PitambarGadhveandShambhuKumardescribeduseofdimplesurfacetoimproveforcedconvectionheattransfer.Heattransferenhancementisbasedonprincipleofscrubbingactionofcoolingfluidinsidethedimple.Surfacedimplespromoteturbulentmixinginflowandenhanceheattransfer.Anexperimentalsetuphasbeendesignedandfabricatedtostudyeffectofdimpledsurfaceonheattransferinrectangularduct.Resultscomparedwithflatsurfacetubeandfoundheattransferenhancementoverthelaterone.P.Gunnasegaran,N.H.Shuaib,andM.F.AbdulJalalintheirstudynumericalsimulationsonfluidflowandheattransfercharacteristicsoverlouveranglefinCompactHeatExchangersarereported.Acomputationaldomainfromthefluidinlettooutletissolved.Theimpactsofusingvariablelouverangles(+2°,+4°,−2°,−4°,anduniformangle20°)andlouveredfinwithvariablefinpitches(1mm,2mm,and4mm)onboththermalandhydraulicofCHEarepresented.TheNusseltnumberishigherforincreasedordecreasedlouveranglecomparedtouniformlouverangle.ThevariablelouveranglepatternsandlouverfinwithsmallerpitchappliedinCHEscouldeffectivelyenhancetheheattransferperformancewithmoderatedegradationofpressuredroppenaltycomparedtoplainfinsurfaceofCHE.Prof.D.K.Chavan,Prof.Dr.G.S.Tasgaonkarexplainedconventionalradiatorsizeisrectangularwhichisdifficultforcircularfantocoverwholesurfacearea.Itcreateslowervelocityzonesatcornersgivinglessheattransfer.Authorhasproposedtoeliminatecornersanddevelopcircularshaperadiatorwhichiscompact,moreefficientandleadstominimumpowerconsumptiontodriveafanandmaximumutilizationofairflow.Consideringlimitationsofconventionaltechniquestoimprovecoolingsystemperformancevariousnewtechnologiesareadopted.Researchisgoingontostabilizetheresults.K.Y.Leong,R.Saidur,S.N.Kazi,A.H.Mamundescribeduseofnanofluidbasedcoolantinenginecoolingsystemanditseffectoncoolingcapacity.Itisfoundthatnano-fluidhavinghigherthermalconductivitythanbasecoolantlike50%/50%waterandethyleneglycol.Itincreasesheattransfer.Soforsameheattransfer,radiatorcoreareacanbereducedcomparedtobaseone.Itfindsbettersolutiontominimizearea.Thermalperformanceofaradiatorusingnanofluidisincreasedwithincreaseinpumpingpowerrequiredcomparedtosameradiatorusingethyleneglycolascoolant.JohnVetroveccarriedworkonenginecoolingsystemwithheatloadaveragingcapacityusingpassiveheatloadaccumulator.Heatloadaccumulatorisphasechangematerialwhichstoresheatgeneratedduringpeakanddissipatesstoredheatduringreducedheatloadcondition.ThisisachievedbysacrificingphasechangeofPCMfromsolidtoliquidorviceversa.Thisleadstocompactheatexchangerforsameheatrejection.Alsoitreducesloadoncoolingsystem.Systemcanhandlehightransientloadsandpermitsfasterwarmupduringcoldenginestart.M.H.Salah,P.M.Frick,J.R.Wagner,D.M.Dawsondiscussedabouthydraulicactuatedcoolingsystem.Actuatorscanimprovetemperaturetrackingandreduceparasiticlosses.Actuatorbasedenginecoolingsystemusescontrollertocontrolcoolantpumpandradiatorfanoperatingconditions.Itprovidespowertosystemcomponentasperrequirement.Thusitregulatespowerconsumptionofsystemcomponentwithcoolingcapacity.Anonlinearbacksteppingrobustcontrollerisusedtoregulateenginecoolanttemperatureinhydraulicbasedthermalmanagementsystem.Proposedcontrollermaintainedthecoolanttemperaturetoitssetpointwithsystemimprovement.Useofthissystemoffersgreaterpowerdensitywithcompactinnature.III.FUTURESCOPEEnginecoolingsystemcancontributeinsomeoftheengineaspectslikereductioninfuelconsumptionthusminimizingexhaustandfuelemission.Thiscanbeachievedbykeepingengineatoptimumthermaloperatingconditions.Alsothermalloadonengine,enginecomponents,lubricatingfluidcanbereduced.Effectiveenginecoolingsystemcanhelptoshortenenginewarmupperiodduringcoldstartandheatlossrecoverytoimprovedrivingcomfort.Reductioninweightandrequiredspacetofitsystemonavehicleisthemostchallengingtaskindevelopingcoolingsystem.Alsoeffortstobetakentoimplementuseofemergingtechnologieslikenano-technologyandtostabilizetheresultsofthesesystems.Inshort,futurechallengesincludedevelopingmorecompact,lightweight,improvedperformanceandeconomicalenginecoolingsystem.IV.PROPOSEDWORKTheproposedworkisconcernedwithdevelopingexcelsheettocalculateheatrejection.Fewinputparameterswillgiveexactidearegardingheatrejection.Sheetwillhelptoestimateeffectofvaryingtubeandfindensity,coolantflowrateetc.onheatrejection.Theoreticalcalculationofradiatorcoresizeandheatrejectionforagivenengineinputs.Validationofcoresizebysimulationsoftwareandcomparingtheoreticalheatrejectionwithsimulationresults.Optimizingcoresizeasperheatrejectionrequirement.3Dmodelingofradiatorcomponentsheader,tubes,finsandtanks.Finiteelementanalysisofradiatortotestitsrobustnessforthermalandpressureloads.Prototypedevelopmenttovalidatetheradiatorperformance.[1]C.Oliet,A.Oliva,J.Castro,C.D.Pe´rez-Segarra,―Parametricstudiesonautomotiveradiators‖,AppliedThermalEngineering,27,2007[2]JPYadavandBharatRajSingh,―StudyonPerformanceEvaluationofAutomotiveRadiator‖,S-JPSET:ISSN:2229-7111,Vol.2,Issue2,2011[3]MazenAl-Amayreh,―ExperimentalStudyofThermalConductivityofEthyleneGlycolWaterMixtures‖,EuropeanJournalofScientificResearch,ISSN1450-216XVol.44No.2,2011[4]P.K.Trivedi,N.B.Vasava,―EffectofVariationinPitchofTubeonHeatTransferRateinAutomobileRadiatorbyCFDAnalysis‖,InternationalJournalofEngineeringandAdvancedTechnology(IJEAT)ISSN:2249–8958,Volume-1,Issue-6,2012[5]PitambarGadhave,ShambhuKumar,―EnhancementofforcedConvectionHeatTransferoverDimpleSurface–Review‖,InternationalMultidisciplinarye–Journal,2012[6]P.Gunnasegaran,N.H.Shuaib,andM.F.AbdulJalal.―TheEffectofGeometricalParametersonHeatTransferCharacteristicsofCompactHeatExchangerwithLouveredFins‖,ISRNThermodynamics,Volume2012[7]Prof.D.K.Chavan,Prof.Dr.G.S.Tasgaonkar,―ThermalOptimizationofFanassistedHeatExchanger(Radiator)byDesignImprovements‖,InternationalJournalofModernEngineeringResearch(IJMER),Vol.1,Issue1,2011[8]K.Y.Leong,R.Saidur,S.N.Kazi,A.H.Mamun,―Performanceinvestigationofanautomotivecarradiatoroperatedwithnanofluidbasedcoolants(nanofluidasacoolantinaradiator)”,AppliedThermalEngineering,30,2010[9]JohnVetrovec,―EngineCoolingSystemwithaHeatLoadAveragingCapability‖,SAEInternational,2008[10]M.H.Salah,P.M.Frick,J.R.Wagner,D.M.Dawson,―Hydraulicactuatedautomotivecoolingsystems—Nonlinearcontrolandtest‖,ControlEngineeringPractice,17,2009汽车散热器性能摘要：汽车发动机冷却系统是负责带走发动机运转过程中产生的多余的热量。它调节发动机的表面温度，来使发动机达到的最佳效率。最近随着发动机动力的发展迫使发动机冷却系统提出新的策略来改进其性能效率。也可以通过减少燃料消耗以及控制发动机排放，减轻环境污染。本文阐述了参数影响散热器性能以及评论的一些传统和现代的方法来提高散热器的性能。指数—发动机冷却系统、性能、散热器一、介绍汽车发动机冷却系统负责发动机运转过程中产生的余热。它调节发动机表面温度对发动机最佳效率。大多数汽车发动机冷却系统由散热器、水泵、冷却风扇、压力上限和恒温器。散热器是系统的主要组件。散热器是一个热交换器,冷却液通过它带走发动机中的热量。热量从热冷却剂转移到外面的空气。散热器总成由三个主要部分组成核心,进口箱和出口。核心有两套,一套管子和风扇。冷却剂流过管子和风扇之间的空气流。热冷却剂将热量传递至风扇。外部空气通过风扇之间气流带走体内的热量。发动机冷却系统的性能的影响因素,比如空气和冷却剂质量以及流率,进气温度,冷却液,风扇类型、翅片间距、管式和管间距等。在设计冷却系统三个最基本的条件是基于以上参数。高海拔:在高空,空气密度低,因此会影响空气质量流率。夏天条件:在夏季周围空气是热即进气温度。最大力量:发动机最大功率的生产条件如车辆爬上坡时,最大热扭矩在这个条件是必需的。考虑所有这些因素，所需要的散热器核心尺寸可能很大。二、文献综述C.Oliet,A.Oliva,J.Castro,C.D研究不同因素影响散热器性能。它包括空气和冷却液流,风扇和空气入口温度。这是观察到散热器的传热和性能受到空气和冷却剂质量流率的影响很大。随着空气和冷却液流增加，冷却能力也增加。当空气进口温度的增加,传热,从而冷却能力降低。小翅片间距和更高的百叶窗式翅片角有较高的传热。风扇密度可以增加直到空气流动和传热速率降低。JPYadav和BharatRajSingh在他们的研究也提出了参数研究汽车散热器。在散热器的安装测试中得到散热性能参数。冷却剂的各种参数包括质量流率,进气冷却剂温度;等多种多样。以下评论期间观察研究:冷却液质量流量的冷却能力的影响散热器与冷却剂流量有直接关系。与冷却流量的价值,有相应增加的效果和冷却能力的价值。冷却液入口温度的影响提高入口温度的冷却液散热器的冷却能力增加。MazenAl-Amayreh在他的研究中发现,经过测试乙二醇+水的热导率,二甘醇+水和三甘醇+水混合物,测量温度从25°C到40°C和浓度范围从25wt%乙二醇75wt%乙二醇。醇浓度的增加会导致热导率降低。增加混合物的温度能够少量的增加热导率。传统的或现代的方法都能够用来提高汽车发动机冷却系统的性能。传统的方法依赖于风扇,管和风扇设计优化。现代技术是基于新技术如纳米技术、热负荷平均容量或发动机冷却系统执行机构的建立。本文综述的一些传统和现代方法主要用来增强散热器性能。P.K.Trivedi,N.B.Vasava认为管间距的最佳配置能够让散热器发挥最高性能。传热表面积增加会改变散热器装配。这导致改变管子的几何形状或者通过修改汽车散热器的排布可以使表面积增加更好的传热。协议的修改管散热器是由学习管距的影响通过CFD分析使用它。结果表明,管间距的减少或增加比最佳距管,传热率降低。PitambarGadhve和ShambhuKumar称使用凹槽提高强制对流传热表面。强化传热技术基于冷却液与凹槽的摩擦。表面凹槽促进流动和湍流混合增强传热。研究实验设置了带凹槽的和普通矩形的散热性能对比。实验结果与平面管对比之后,发现带有凹槽的传热增强。p.Gunnasegaran:h.Shuaib,m·f和M.F.AbdulJalal在他们的研究中说道在流体流动和传热特性数值模拟百叶窗角度紧凑热交换器。从流体计算域入口出口是解决。使用变量的影响百叶窗角度(+2°,+4°,-2°,-4°,和统一的角度20°)变量和装有百叶窗板的鳍鳍球(1毫米,2毫米和4毫米)的热力和水力切。增加或减少的努塞尔特数较高百叶窗角度而统一的百叶窗角度。变量模式和百叶窗式翅片百叶窗角度较小;该应用能有效地提高传热性能与中度退化的压降比平翅片表面切处罚。Prof.D.K.Chavan,Prof.Dr.G.S.博士解释说传统散热器大小循环风扇难以覆盖矩形整个表面。它创造了低速度区角落给更少的热量转移。作者提出了消除角落和发展更为紧凑的圆形散热器,来提高效率,以便达到最小功耗驱动风扇和最大利用气流。考虑传统技术的局限性,提高冷却系统性能采用各种新技术。研究逐渐变成现实。K.Y.Leong,R.Saidur,S.N.Kazi,A.H.Mamun描述使用基于nanofluid冷却液在发动机冷却系统及其对冷却能力的影响。发现thatnano-fluid有更高的热导率比基础冷却剂50%/50%水和乙二醇。它具有更好的导热性。对于相同的传热,散热器核心区域相比可以减少基地之一。找到更好的解决方案来减少区域。使用nanofluid散热器的热性能相比相同泵功率使用乙二醇作为冷却剂的散热器要好很多。JohnVetrovec使用热负荷蓄电池发动机冷却系统的被动进行热负荷平