畢業設計（論文）外文參考資料及譯文譯文題目：AutomotiveRadiatorPerformance汽車散熱器性能學生姓名：學號：專業：所在學院：指導教師：職稱：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汽車散熱器性能摘要：汽車發動機冷卻系統是負責帶走發動機運轉過程中產生的多余的熱量。它調節發動機的表面溫度，來使發動機達到的最佳效率。最近隨著發動機動力的發展迫使發動機冷卻系統提出新的策略來改進其性能效率。也可以通過減少燃料消耗以及控制發動機排放，減輕環境污染。本文闡述了參數影響散熱器性能以及評論的一些傳統和現代的方法來提高散熱器的性能。指數—發動機冷卻系統、性能、散熱器一、介紹汽車發動機冷卻系統負責發動機運轉過程中產生的余熱。它調節發動機表面溫度對發動機最佳效率。大多數汽車發動機冷卻系統由散熱器、水泵、冷卻風扇、壓力上限和恒溫器。散熱器是系統的主要組件。散熱器是一個熱交換器,冷卻液通過它帶走發動機中的熱量。熱量從熱冷卻劑轉移到外面的空氣。散熱器總成由三個主要部分組成核心,進口箱和出口。核心有兩套,一套管子和風扇。冷卻劑流過管子和風扇之間的空氣流。熱冷卻劑將熱量傳遞至風扇。外部空氣通過風扇之間氣流帶走體內的熱量。發動機冷卻系統的性能的影響因素,比如空氣和冷卻劑質量以及流率,進氣溫度,冷卻液,風扇類型、翅片間距、管式和管間距等。在設計冷卻系統三個最基本的條件是基于以上參數。高海拔:在高空,空氣密度低,因此會影響空氣質量流率。夏天條件:在夏季周圍空氣是熱即進氣溫度。最大力量:發動機最大功率的生產條件如車輛爬上坡時,最大熱扭矩在這個條件是必需的?？紤]所有這些因素，所需要的散熱器核心尺寸可能很大。二、文獻綜述C.Oliet,A.Oliva,J.Castro,C.D研究不同因素影響散熱器性能。它包括空氣和冷卻液流,風扇和空氣入口溫度。這是觀察到散熱器的傳熱和性能受到空氣和冷卻劑質量流率的影響很大。隨著空氣和冷卻液流增加，冷卻能力也增加。當空氣進口溫度的增加,傳熱,從而冷卻能力降低。小翅片間距和更高的百葉窗式翅片角有較高的傳熱。風扇密度可以增加直到空氣流動和傳熱速率降低。JPYadav和BharatRajSingh在他們的研究也提出了參數研究汽車散熱器。在散熱器的安裝測試中得到散熱性能參數。冷卻劑的各種參數包括質量流率,進氣冷卻劑溫度;等多種多樣。以下評論期間觀察研究:冷卻液質量流量的冷卻能力的影響散熱器與冷卻劑流量有直接關系。與冷卻流量的價值,有相應增加的效果和冷卻能力的價值。冷卻液入口溫度的影響提高入口溫度的冷卻液散熱器的冷卻能力增加。MazenAl-Amayreh在他的研究中發現,經過測試乙二醇+水的熱導率,二甘醇+水和三甘醇+水混合物,測量溫度從25°C到40°C和濃度范圍從25wt%乙二醇75wt%乙二醇。醇濃度的增加會導致熱導率降低。增加混合物的溫度能夠少量的增加熱導率。傳統的或現代的方法都能夠用來提高汽車發動機冷卻系統的性能。傳統的方法依賴于風扇,管和風扇設計優化?，F代技術是基于新技術如納米技術、熱負荷平均容量或發動機冷卻系統執行機構的建立。本文綜述的一些傳統和現代方法主要用來增強散熱器性能。P.K.Trivedi,N.B.Vasava認為管間距的最佳配置能夠讓散熱器發揮最高性能。傳熱表面積增加會改變散熱器裝配。這導致改變管子的幾何形狀或者通過修改汽車散熱器的排布可以使表面積增加更好的傳熱。協議的修改管散熱器是由學習管距的影響通過CFD分析使用它。結果表明,管間距的減少或增加比最佳距管,傳熱率降低。PitambarGadhve和ShambhuKumar稱使用凹槽提高強制對流傳熱表面。強化傳熱技術基于冷卻液與凹槽的摩擦。表面凹槽促進流動和湍流混合增強傳熱。研究實驗設置了帶凹槽的和普通矩形的散熱性能對比。實驗結果與平面管對比之后,發現帶有凹槽的傳熱增強。p.Gunnasegaran:h.Shuaib,m·f和M.F.AbdulJalal在他們的研究中說道在流體流動和傳熱特性數值模擬百葉窗角度緊湊熱交換器。從流體計算域入口出口是解決。使用變量的影響百葉窗角度(+2°,+4°,-2°,-4°,和統一的角度20°)變量和裝有百葉窗板的鰭鰭球(1毫米,2毫米和4毫米)的熱力和水力切。增加或減少的努塞爾特數較高百葉窗角度而統一的百葉窗角度。變量模式和百葉窗式翅片百葉窗角度較小;該應用能有效地提高傳熱性能與中度退化的壓降比平翅片表面切處罰。Prof.D.K.Chavan,Prof.Dr.G.S.博士解釋說傳統散熱器大小循環風扇難以覆蓋矩形整個表面。它創造了低速度區角落給更少的熱量轉移。作者提出了消除角落和發展更為緊湊的圓形散熱器,來提高效率,以便達到最小功耗驅動風扇和最大利用氣流?？紤]傳統技術的局限性,提高冷卻系統性能采用各種新技術。研究逐漸變成現實。K.Y.Leong,R.Saidur,S.N.Kazi,A.H.Mamun描述使用基于nanofluid冷卻液在發動機冷卻系統及其對冷卻能力的影響。發現thatnano-fluid有更高的熱導率比基礎冷卻劑50%/50%水和乙二醇。它具有更好的導熱性。對于相同的傳熱,散熱器核心區域相比可以減少基地之一。找到更好的解決方案來減少區域。使用nanofluid散熱器的熱性能相比相同泵功率使用乙二醇作為冷卻劑的散熱器要好很多。JohnVetrovec使用熱負荷蓄電池發動機冷卻系統的被動進行熱負荷平