汽车专业毕业设计翻译

SeminaroftheAssemblyofEuropeanRegionsonRenewableandAlternativeSourcesofEnergy,1-2July2005,Porjus,Norrbotten(S)PAGEPAGE9WORKSHOP3:CLEANVEHICLEANDCITYCENTRETRANSPORTSOLUTIONSInterestincleaner,lesspollutingvehiclesandfuelhasgrownrapidlyoverrecentyears.Thisinteresthasbeenspurredbythreefactors:* Increasingawarenessandconcernregardingtheenvironmentaleffectsofvehicleuse* Thefinancialsavingsthatvehicleoperatorscanmakebyswitchingtocleanervehicles* Increasinglystringentemissionslegislation. Biomassistheonlyrenewablesourceoftransportationfuels.Theserenewablefuels,calledbiofuels,producefeweremissionsthanpetroleumfuels.TheEuropeanUnionispromotingthemarketingofgreenercarsviaacombinationofbindingandnon-bindingmeasures.'Cleanvehicles'includelowemissionconventionallyfuelledvehiclesaswellasthosepoweredbyalternativefuels.Theproductionofsuchvehicles,generatinglessCO2emissions,requiresinnovationinfuels,alternativepower-traintechnology,noisereductionandnewmaterials.Overall,theEuropeanUnion’saimistoreach-by2010atthelatest-anaverageCO2emissionfigureof120g/kmforallnewpassengercarsmarketedintheUnion.Presentationofthemostimportanttechnologiesandfuelsisgivenbelow.

Source:EuropeancarindustryandfuturechallengesWith42%ofglobalproductioncomingfromtheEUin2002,theregionhasthelargestsinglemarketforpassengercarsintheworldandiswellpositionedtoleverageeconomiesofscaleandscope.ButonemajorchallengeliesintheadvantageJapanesecarmakershavegainedindevelopingenvironmentallyfriendlytechnologies,“mostprominentlythedevelopmentofnewtechnologies/fuelcombinations,includingfuelcells”AccordingtotheCommission’s2004competitivenessreport:DutchPresidency:ResultsofthecompetitivenessCouncil–Competitivenesspackageandautomativeindustry(nov25AccordingtotheCommission’s2004competitivenessreport:DutchPresidency:ResultsofthecompetitivenessCouncil–Competitivenesspackageandautomativeindustry(nov25th,2004)Biofuels(I):marketshareandmakingprocess-Biofuelscurrentlyrepresentaround0.3percentonlyofdieselandgasolineconsumptionintheEU.InMay2003,theCommissionadoptedadraftdirectivewhichrequiresMemberStatestotakethenecessarymeasurestoincreasethemarketshareofbiofuels.TheMemberStatesmustensurethattheminimumshareofbiofuelssoldontheirmarketsis2percentby31December2005atthelatest,and5.75percentbyDecember2010.AnyMemberStatesettinglowerobjectiveswillhavetojustifythisonthebasisofobjectivecriteria.TheCommissionestimatesthataneffectiveimplementationofthe2003BiofuelsDirectivecouldsave19milliontonnesofoilby2010.-Technicallyspeaking,biofuelscanbepreparedfromplantsaccordingtotwothreemajormethodsbasedeitherontheuseof1)glucidesorcelluloseorof2)fatsorof3)anyorganicmaterial.Inthefirstmethod,thestarchcontainedinthetuber(beetroot,potato)ortheseed(cereals)aswellastheglucosecontainedinthesap(canesugar)undergovariouschemicalprocesses–hydrolysispossiblyandalcoholtransformation.Themainbiofuelspreparedusingthismethodareethanolandethyltertiarybutylether(ETBE),whichbothcanbemixedwithpetrolinahigherproportionthanethanolHowever–accordingtoEUlegislation,mixturescontaining5–30%ethanolareprohibited.Higherandlowerblendsthanthisareallowed.(Directives1998/70/EC,2003/17/EGand2003/30/EG).Researchersareinvestigatingtechnologiesformakingethanolfromthecellulose(fiber)componentinbiomass,likemunicipalsolidwastesandagriculturalresiduesleftinthefieldafterharvest.ApilotplantisoperatinginSwedensincemorethanayear.Technicallythisisanexcellentmethod,thoughstilltooexpensive.ThistypeofEthanolmadefromorganicfeedstockissometimescalledbioethanoltodistinguishitfromethanolmadefromoil.Bioethanolreducesexhaustemissionsfromcarbonmonoxideandhydrocarbons.Inaddition,bydisplacinggasolinecomponentssuchassulfur,bioethanolhelpsreducetheemissionsoftoxiceffluentsfromautomobiles.Mostimportantisthatbioethanolreducesemissionsofclimategases(CO2)with70–95%,dependingonproductionmethods.Inthesecondmethod,vegetaloilsfromrapeoilmeal,orevenfromsunflower,whicharemainlytriglycerides,lead,afteresterification,todiesterswhicharealsousedasbiofuels.Thisiscommonlyknownasbiodiesel.Biodieselreducesemissionsofcarbonmonoxide,hydrocarbonsandclimategases,butincreasestheemissionsofparticulates(PM10)andnitrogeneoxideNOxdramatically.Particlefilterscancuretheparticleemissions,butthereisyetnocommerciallyavailablemethodtoreduceNOx.HencebiodieselisbestusedinareasnotsufferingfromotherhighNOx-emissionsInthethirdmethod,organicmateriallikesewagefromwatertreatmentplants,restaurantwaste,offalsfromslaughteries,surpluscropsetcarefermentedanaerobicallytoproducemethaneandcarbondioxide(CO2).ThisiscurrentlycommonlypractisedinmostEuropeancities.AftertakingtheCO2away(bye.g.waterscrubber),thisiscalledBiogasandisthecleanestfuelthatiscommerciallyavailable.Biogasemitsalmostnohealthhazardousorclimategasesatall.Biofuels(II):presentationofthevariousfuelsandtechnologies-LiquifiedPetroleum(LPG)LPGismostlypropaneandisusedextensivelywhereportablegasisrequired.Itisproducedduringtheoilrefiningprocess.LPGisagasatroomtemperatureandpressure,butisstoredasaliquidunderpressurebothon-boardvehiclesandatdepots.Apartformthefuelstorageanddeliverymechanisms,LPGenginesareverysimilartopetrolengines,anddeliversimilarperformance.Infact,mostLPGvehiclesarebi-fuel,allowingthedrivertochangefromLPGtopetrolandviceversa.Inmotorvehicles,itaddresses,tosomeextent,theproblemsofpollutionasanalternative,mainlytopetrol.Althoughitisnotrenewableandisstillbasedonfossilfuels,LPGisclaimedtobecleaner.Forexample,theUKgovernmentisencouragingitsusebylargetaxconcessionsandsubsidiesforconvertingsomepetrolcars.TheVauxhallVectraDualfuelSource:NaturalgasApartfrombeingacleansourceofenergy,

naturalgasofferstheadvantageofensuringsecurityofsupply.Itisapproximately92%methane,withthereminderbeingamixtureofnitrogen,ethane,propaneandothergases.Naturalgas,unlikeLPG,doesnotliquefyeasily,soisstoredonboardvehicleseitherincompressedorliquefiedform.Henceitisanexcellentenginefuel,butneitherformofon-boardfuelstorageisasconvenientasthestorageofpetrolordiesel.Forthisreasonthemajorityofnaturalgasvehiclesareheavy-dutytrucksandbuses,aslargerandheavierfueltanksposelessofaproblemforthesevehicles.The

2003ReportofthehighlevelexpertsonAlternativeFuelsfortheCommissioncomestotheconclusionthatnaturalgasistheonlyalternativefuelwithpotentialforsignificantmarketsharewellabove5%by2020whichcouldpotentiallycompetewithconventionalfuelsintermsoftheeconomicsofsupplyinamaturemarketscenario.(Theywerenottotallyup-dated–seeunderEthanolandBiogas)"Natural”gascouldgainabroadermarketshareifsupportedbylong-termtaxandexcisedutyadvantages,providingstableconditionsuntilabroadmarkethasdeveloped.Maturevehicletechnologyisavailable,butdiversityofproductsandservicesstillneedtobeimproved,"saysthereport.TosupportabroadercommercialisationofnaturalgasvehiclesatEuropeanlevel,thereportrecommendsthatcodesandstandardsshouldbeharmonisedfortheuseofnaturalgasasamotorvehiclefuel.

BiogasMostofthecharacteristicsfornaturalgasalsoappliesforbiogas.TechnicallybiogasisthesamegasasNaturalgas–thoughrenewable–andallvehiclesthatcanusenaturalgas,canalsousebiogas.Oppositetowhatissaidabove–bothinEuropeandgloballytherearemuchmorelight-dutyvehiclesinoperationthanHeavy-duty.Furthermore-allmodernbiogas/naturalgaslight-dutyvehiclesaredual-fuels,withonetankforgasandoneforpetrol,givingthepossibilitytodrivealsoinareaswherethefuellinginfrastructureisnotfullydevelopedFurthermore–producedinreasonablescale,biogasiseconomicallycompetitivewithdiesel.AccordingtoSwedishandFinnishstudiesbiogashasthepotentialtosubstituteabout10%ofthecurrentenergyusedfortransport.BiogasiscurrentlyusedastransportfuelinSweden,FranceandSwitzerland.NetherlandandPolenareabouttostartwithinafewyears.EthanolEthanolisthemostcommonvehiclebiofuelintheworld–morethan6millioncarsdriveonethanoltoday,mostoftheminBrazilandinUSA.Aspureethanolmaygivestartingproblemsduringcoldconditions,100%ethanolisonlyusedundercontrolledcircumstances(e.g.inbusfleets)orinhotclimates.Normallyethanolisblendedwith15%petroltoavoidthisproblem.Allethanolcarscanalsorunonpetrol,oranymixtureofethanolandpetrol,meaningthatyoucanchoosetofillyourcarwithpetrolifthereisnoethanolstationathand.AccordingtoTheInternationalEnergyAgencyIEA,Ethanolhasthepotentialtosubstitute10%ofthepetroland3%ofthedieselby2020.Whenthecellulose-basedethanoliseconomicallyviable,thispotentialincreasesdramatically.-BatteryelectricvehiclesBatteryelectricvehiclesproducenoemissionsthemselvesandaregenerallychargedfromthenationalgridviastandardthreepinsockets.Severaldifferentbatterytechnologiesexistincludinglead-acid(nowquitedated),nickel-cadmium,nickel-metalhydride,andlithiumion.MostelectricvehiclestodayarePeugeotsorCitroens,whichusenickel-cadmiumcells.Withtheirlimitedranges,batteryvehiclesarenotappropriatetoreplaceconventionalvehiclesforthemajorityofapplications,buttheyareappropriateforcertainnichemarketssuchasurbandeliveryvehicles.TheelectricthinkcarSource:HybridsTheterm‘hybrid’usuallyreferstoavehiclethathasbothanelectricmotorandaninternalcombustionengine(ICE).Thesehavetraditionallybeeneither‘serieshybrids’inwhichtheICEactsasageneratorproducingelectriccurrentforthemotor,or‘parallelhybrids’inwhichboththeelectricmotorandtheICEcandrivethewheels.BoththeToyotaPriusandtheHondaInsightmakeuseofinnovativenewhybridtechnologyandproduceimpressivefueleconomyandemissionsresults.TheToyotaPriusSource:-HydrogenandFuelcellsHydrogenisacleanandstorableenergyvectorthatcanbeproducedfromavarietyofprimaryenergysources(includingfossil,renewableandnuclear).InSeptember2003,theCommissionpresentedaCommunicationproposingthecreationofaEuropeanHydrogenandFuelCellsTechnologyPartnershipinordertopromotehydrogenresearchinEurope.Thisisregardedasapotentiallyabundantalternativesourceofenergy.TheCommissionlaunchedthe'EuropeanHydrogenPlatform'inJanuary2004.Hygrogen'sadvocatesclaimthatthe'hydrogeneconomy'wouldsolveenvironmentalproblems(suchasglobalwarmingandpollution)andsecureindependenceofenergysupply.Afuelcellisaconversiondevicethatcombineshydrogenfuelandoxygenfromtheairtoproduceelectricity,heatandwater.Itwasinventedwaybackinthe19thcenturybuthasnotbecomepopularinthemassmarket,partlybecausetheyareveryexpensiveandthealternativesweremoreappropriatefortheirtime.Inadditiontheycanbelarge,difficulttooperateandthetechnologyiscomplex.Moreresearchanddevelopmentisneededbutneverthelesstheyarecurrentlybeingusedinasmallway.Nowthattheneedforcleanenergy,withloworzeroemission,isurgentlyrecogniseditistobeexpectedthatfuelcellswillbecomepracticalalternativessoon.FuelCellBusinGermanySource:www.envocare.co.ukCleanerpetrolanddieselEmissionsfrompetrolanddieselengineshavebeensignificantlyreducedoverthelasttenyears,drivenmainlybyEuropeanlegislation,andwillcontinuetobereducedinthefuture.Loweremissionsfromconventionalfuelsareachievedbyarangeoftechnologiesincludingcleanerformulationsofthefuels,aftertreatmenttechnologiesthatremovepollutantsfromthevehicleemissions,andbyimprovementstofueldeliveryandcombustionprocesses.Sources:DutchPresidency:ResultsofthecompetitivenessCouncil–Competitivenesspackageandautomativeindustry(nov25th,2004)Cleanurbantransport–resultsfromtheresearchProgramme–EuropeanCommission–July2001FUELCELLSWhiletherearedifferenttypesoffuelcells,protonexchangemembraneor"PEM"fuelcellsarenowusedinmostprototypefuelcellvehicles.

EachPEMfuelcellusesathin

catalyst-coatedmembranethatisenclosedbetweengraphiteorceramicplates.

Onesideofthemembraneactsasananode,andisexposedtohydrogengas.

Theothersideofthemembraneservesasthecathode,andisbathedinairtoprovideoxygen.

Attheanodeside,acatalyticreactionoccurs,causing

thehydrogentobeseparatedintoprotonsandelectrons.

Theprotonsdiffusethroughthemembraneandreachthecathode.

Theelectrons,however,cannotpassthroughthismembraneandgoroundthemembranetoreachthecathodethuscausinganelectriccurrentastheytravel.

Oncetheelectronsreachthecathode,anothercatalyticreactiontakesplaceastherecombinedhydrogenatomsjoinwithoxygentoproducewater.IndividualPEMfuelcellsareassembledtogethertoformfuelcellstackswhichproduceenoughelectricitytorunacar,minivans,sportutilityvehiclesandtransitbuses.Although,fuelcellvehiclesemitonlywater,thesourceofthehydrogenasfuelcanbelesspollutionfree.Thereareseveralmethodsofsupplyinghydrogen:

centrallylocatedhydrogenproductionplantscoulddistributethehydrogeninliquidformtolocalfuelstationswhocouldthendispenseittofuelcellvehiclescapableofstoringthehydrogenineitherliquidorgaseousformintanksonthevehicle.

(Liquidhydrogenmustbestoredatextremelylowtemperatureswhereasgaseoushydrogenmustbestoredatveryhighpressure.)Somecompaniesarenowworkingonalternativestothesespecialisedstoragetanksincludingametalhydridestoragedevicethatabsorbshydrogen.

Thiswill

increasetheamountofhydrogenthatcanbestoredonthevehicles.Fuelssuchasnaturalgas,methanol,ethanol,propaneandpetrolallhavehydrogenaspartoftheirmolecularstructure.

Byusinganon-board"reformer"itispossibletoremovethehydrogenfromthesefuelsanduseittodirectlypowerthefuelcell.

Thisdirectly

benefitsmotoristasitavoidstheneedtouse

large,heavypressuregasstoragetanksandgivesthevehiclealongerrange.

A

liquidfuellikemethanolcanbestoredanddistributedinmuchthesamewayaspetrolisnow.Fromanemissionsperspectiveifpurehydrogenisusedasafuel,theonlytailpipeemissioniswaterbutfuelcellvehiclesthatusereformerswillemitsmallamountsofregulatedpollutantslikecarbonmonoxide.However,theselevelsaremuchlowerthanintheinternalcombustionenginesbecauseafuelcell

powerunitoperatesatmuchlowertemperatures.

基于C8051F单片机直流电动机反馈控制系统的设计与研究基于单片机的嵌入式Web服务器的研究MOTOROLA单片机MC68HC（8）05PV8/A内嵌EEPROM的工艺和制程方法及对良率的影响研究基于模糊控制的电阻钎焊单片机温度控制系统的研制基于MCS-51系列单片机的通用控制模块的研究基于单片机实现的供暖系统最佳启停自校正（STR）调节器单片机控制的二级倒立摆系统的研究基于增强型51系列单片机的TCP/IP协议栈的实现基于单片机的蓄电池自动监测系统基于32位嵌入式单片机系统的图像采集与处理技术的研究基于单片机的作物营养诊断专家系统的研究基于单片机的交流伺服电机运动控制系统研究与开发基于单片机的泵管内壁硬度测试仪的研制基于单片机的自动找平控制系统研究基于C8051F040单片机的嵌入式系统开发基于单片机的液压动力系统状态监测仪开发模糊Smith智能控制方法的研究及其单片机实现一种基于单片机的轴快流CO〈,2〉激光器的手持控制面板的研制基于双单片机冲床数控系统的研究基于CYGNAL单片机的在线间歇式浊度仪的研制基于单片机的喷油泵试验台控制器的研制基于单片机的软起动器的研究和设计基于单片机控制的高速快走丝电火花线切割机床短循环走丝方式研究基于单片机的机电产品控制系统开发基于PIC单片机的智能手机充电器基于单片机的实时内核设计及其应用研究基于单片机的远程抄表系统的设计与研究基于单片机的烟气二氧化硫浓度检测仪的研制基于微型光谱仪的单片机系统单片机系统软件构件开发的技术研究基于单片机的液体点滴速度自动检测仪的研制基于单片机系统的多功能温度测量仪的研制基于PIC单片机的电能采集终端的设计和应用基于单片机的光纤光栅解调仪的研制气压式线性摩擦焊机单片机控制系统的研制基于单片机的数字磁通门传感器基于单片机的旋转变压器-数字转换器的研究基于单片机的光纤Bragg光栅解调系统的研究单片机控制的便携式多功能乳腺治疗仪的研制基于C8051F020单片机的多生理信号检测仪基于单片机的电机运动控制系统设计Pico专用单片机核的可测性设计研究基于MCS-51单片机的热量计基于双单片机的智能遥测微型气象站MCS-51单片机构建机器人的实践研究基于单片机的轮轨力检测基于单片机的GPS定位仪的研究与实现基于单片机的电液伺服控制系统用于单片机系统的MMC卡文件系统研制基于单片机的时控和计数系统性能优化的研究基于单片机和CPLD的粗光栅位移测量系统研究单片机控制的后备式方波UPS提升高职学生单片机应用能力的探究基于单片机控制的自动低频减载装置研究基于单片机控制的水下焊接电源的研究基于单片机的多通道数据采集系统基于uPSD3234单片机的氚表面污染测量仪的研制基于单片机的红外测油仪的研究96系列单片机仿真器研究与设计基于单片机的单晶金刚石刀具刃磨设备的数控改造基于单片机的温度智能控制系统的设计与实现基于MSP430单片机的电梯门机控制器的研制基于单片机的气体测漏仪的研究基于三菱M16C/6N系列单片机的CAN/USB协议转换器基于单片机和DSP的变压器油色谱在线监测技术研究基于单片机的膛壁温度报警系统设计基于AVR单片机的低压无功补偿控制器的设计基于单片机船舶电力推进电机监测系统基于单片机网络的振动信号的采集系统基于单片机的大容量数据存储技术的应用研究基于单片机的叠图机研究与教学方法实践基于单片机嵌入式Web服务器技术的研究及实现基于AT89S52单片机的通用数据采集系统基于单片机的多道脉冲幅度分析仪研究机器人旋转电弧传感角焊缝跟踪单片机控制系统基于单片机的控制系统在PLC虚拟教学实验中的应用研究基于单片机系统的网络通信研究与应用基于PIC16F877单片机的莫尔斯码自动译码系统设计与研究基于单片机的模糊控制器在工业电阻炉上的应用研究基于双单片机冲床数控系统的研究与开发基于Cygnal单片机的μC/OS-Ⅱ的研究基于单片机的一体化智能差示扫描量热仪系统研究HYPERLINK"/detail.ht