专业英语ppt课件汽车专业英语ppt课件-与汽车专业英语读译教程配套-宋进桂制作8-U4TA

UNIT4GASOLINEFUELINJECTIONTEXTAGasolineDirectInjection(GDI)andThrottle-by-wire,PROFESSIONALENGLISH,UNIT3GASOLINEFUELINJECTIONTEXTAGasolineDirectInjection(GDI)andThrottle-by-wireGasolineDirectInjectionMitsubishiGDIVolkswagenAGsdirect-injection(FSI)ToyotaDIengineElectronicThrottleThrottle-By-Wire,本次课学习内容,本次课学习目标,掌握GDI系统的特点掌握GDI系统的原理掌握电子节气门原理,NEWWORDS,drasticdrstika.激烈的，猛烈的GDI=gasolinedirectinjection(汽油直接喷射)forerunnerf:rnn.先驱（者），先锋，祖先CVT=continuouslyvariabletransmission（无级变速器）characteristicskriktristiksn.特性（曲线）exoticigztikn.奇异的，外来的，异国情调的FSI=fuelstraightinjection燃油直接喷射layoutleiautn.规划，设计（图案），布置stickstikn.棒，棍；v.粘住，粘铁estateisteitn.状态，时期，不动产,signaturesigntn.签名，署名，信号acronymkrnimn.只取首字母的缩写linchpinlintpinn.关键justicestisn.正义，正当，公平，欣赏，审判effervescentefvesnta.冒泡的，兴奋的superbsju:p:bn.壮丽的，华美的，最上等的，无比的drawbackdr:bkn.缺点，障碍brilliantbrilinta.灿烂的，闪耀的DI=directinjected,directinjection直接喷射crucialkru:()la.至关紧要的nitrogennaitr()nn.氮lean-burnli:n-b:na.稀薄燃烧,incorporateink:preitv.合并，混合，组成公司；a.合并的，一体化的liplipn.嘴唇，唇缘helicalhelik()la.螺旋状的quintessentialkwintisenla.精髓的，精萃的，典范的，本质的stratifystrtifaiv.使成层promoteprmoutv.促进，加速，激励，提升vicinityvisinitin.附近，临近，接近coincidentalkouinsident()la.一致的，符合的，巧合的purifypjurifaiv.净化，使纯净occludeklu:dv.使闭塞，吸收stoichiometricstikimetrika.化学当量的，理想配比的,homogeneoushmi:njsa.相似的，均匀的crossoverkrsouvn.跨越，交叉，交迭，穿过throttle-by-wirertl-bai-wai线控节气门servomotors:voumoutn.伺服电动机，辅助电动机，伺服传动装置ASR=anti-slipregulator或accelerationslipregulation防滑调节装置ABS=anti-lockbrakingsystem防抱死制动系统takeoffteikfn.起飞，开始beatbi:tn.敲打，拍子;v.打，打败trusttrstv.&n.信任，信赖limp-homelimp-houmn.跛行回家,makeup补充，修理，整理，形成allbut几乎，差不多turbolag增压滞后inconjunctionwith连同一起volumetricefficiency容积效率VVT-i(VariableValveTiming,intelligent)智能型可变气门定时cruisecontrol巡航控制tractioncontrol牵引控制laydown设计，制定，主张,PHRASESANDEXPRESSIONS,GasolineDirectInjection(GDI)andThrottle-by-wireGasolineDirectInjectionConventionalgasolineenginesaredesignedtouseanelectronicfuelinjectionsystem,replacingthetraditionalmechanicalcarburetionsystem.Multi-pointinjection(MPI),wherethefuelisinjectedthrougheachintakeport,iscurrentlyoneofthemostwidelyusedsystems1.AlthoughMPIprovidesadrasticimprovementinresponseandcombustionquality,itisstilllimitedduetofuelandairmixingpriortoenteringthecylinder.Tofurtherincreaseresponsetimeandcombustionefficiency,whileloweringfuelconsumptionandincreasingoutput,systemsmayusedirectinjection.Gasolinedirectinjectionenginesareengineeredtoinjectthegasolinedirectlyintothecylinderinamannersimilartodieseldirectinjectionengines.,Directinjectionisdesignedtoallowgreatercontrolandprecision,resultinginbetterfueleconomy.Thisisaccomplishedbyenablingcombustionofanultra-leanmixtureundermanyoperatingconditions.Directinjectionisalsodesignedtoallowhighercompressionratios,deliveringhigherperformancewithlowerfuelconsumption.Currently,directinjectiongasolineenginesarebeingdeployedthroughouttheworldinpassengercars.,MitsubishiGDIMitsubishiMotorsisaimingtoachievebothlowfuelconsumptionandhighoutput.MMCisaworldforerunnerinthedevelopmentofdirectcylinderinjectiongasolineengines,knownasGDI,whichwerefirstintroducedinthe1996Galant.GDIsuppliesfueldirectlytotheinsideofthecylinder.Avarietyofair-fuelmixturescanbecreatedaccordingtochangesinthefuelinjectiontiming.UsingmethodsandtechnologiesuniquetoMitsubishi,theGDIengineprovidesbothlowerfuelconsumptionandhigheroutput.Thisseeminglycontradictoryanddifficultfeatisachievedwiththeuseoftwocombustionmodes.Putanotherway,injectiontimingschangetomatchengineload.,Ultra-leanCombustionModeUndermostnormaldrivingconditions,uptospeedsof120km/h,theMitsubishiGDIengineoperatesinultra-leancombustionmode,resultinginlessfuelconsumption.Inthismode,fuelinjectionoccursatthelatterstageofthecompressionstrokeandignitionoccursatanultra-leanair-fuelratioof30:40(35:55,includingEGR).SuperiorOutputModeWhentheGDIengineisoperatingwithhigherloadsorathigherspeeds,fuelinjectiontakesplaceduringtheintakestroke.Thisoptimizescombustionbyensuringahomogeneous,coolerair-fuelmixturewhichminimizesthepossibilityofengineknocking.ThesetwomodesarerepresentedinFigure4-1.ThepistonoftheGDIengineisshowninFigure4-2.,Fig.4-1TwocombustionmodesoftheGDI,Fig.4-2ApistonofMitsubishiGDIengine,Inaddition,theGDI-CVTintroducedinthe2000LancersignificantlyreducesenergylossbyintegratedcontrolthatmakesthemostofGDIcharacteristics3.High-precisiontorquecontrolandlargerangeforlowfuelconsumptionaswellastheCVTcharacteristicsofquickandcontinuouscontrolofthelargegearchangeratiosenabletopclasslevelfueleconomyandanexceptionallysmoothride4.VolkswagenAGsdirect-injectionTheAudisnew2LI-4improvesgreatlyonthehighstandardssetbythe1.8Titreplaces.WhiletheAudimissestheexotic5-valve-per-cylinderconfigurationofthe1.8T,the2LFSImakesupforitsmore-conventional4-valvelayoutbystickingafuelinjectorintothecombustion-chamber,realestatethatusedtobeoccupiedbyAudissignaturefifthvalve.,Directinjectiongasoline(DIG)technologyisthefastest-emergingpowerandeconomyenhancinginnovationinthepowertrainsectorandwiththe2LFSI(VolkswagenAGsdirect-injectionacronymforFuelStraightInjection),AudianditsVWparentisleadingthepack.AudisaysFSIwillbeitsgasoline-enginelinchpingoingintothefuture.Soon,everyAudi-brandenginewillfeaturetheFSIsystem.FSIaddsnewlevelsofpowerandtorque,yetalsodeliversfuel-economygainsthat,attheleast,offsetwhattypicallywouldbelostingeneratingincreasedpower.Forexample,althoughthe2LFSIdevelops30hpand40-pluslb-ft.(41Nm)moretorquethanthesmaller1.8T(asusedbyAudi),acontinuouslyvariabletransmission-equippedA4withthenewenginegets20%betterfueleconomyincitydrivinganddoes10%betteronthehighway.,ThenumbersdontdojusticetotheeffervescentnatureofthenewI-4.Thethrottleresponseisthelastwordinimmediate,andthisisoneofthoserare4-cyls.Thatcontinuallyhitsthefuelcutofflongbeforenoiseandvibrationsuggestagearchangeisinorder.Twinbalanceshaftscertainlyhelpinthatregard.The2Lmillhasavariable-lengthintakemanifoldandasuperbBorgWarnerTurboSystemsvariable-turbineturbochargerthat,whencombinedwithFSI,allbuteliminatesturbolag,justaboutthelastremainingdrawbackofturbocharging.The2LI-4isclaimedtobetheworldsfirstautomotiveenginetocombineDIGtechnologyandturbocharging.IfAudisbrilliantnew4-cyl.engineistypicalofwhathappenswhendirectinjectionandturbocharginggettogether,weexpecttoseemuchoftheautoindustryfollowinAudisinnovativefootsteps.,ToyotaDIengineToyotaMotorCorp.hasdevelopeda4-stroke,direct-injected(DI)gasolineengine.InconjunctionwiththenewDIengineisanothercrucialitem:aproduction-ready3-wayexhaustcatalystcapableofoxidizingtheoxidesofnitrogen(NOX)-richexhaustinherenttolean-burnengines.Thenewengine,designatedD-4byToyota,isa2LDOHCinline4-cyl.Compressionratiois10:1,andtheengineoperatesefficientlyonregularunleadedgasoline.TheD-4incorporatesahighlyoptimizedcombustionchamber:Thepistoncrownsarefittedwithalipped,cup-likeformationthatfocusestheinjectedair/fuelmixturetightlyaroundthesparkplugformaximumburn.Intakeairisdrawnthroughhelicalportsthatcreateahighdegreeofhorizontalswirl,whichToyotasayscombineswiththelippedcombustionchambertonotonlymaintainhighlystablecombustionaquintessentialproblemforlean-burnersbutalsotostratifytheair/fuelmixture.,Additionalswirlispromotedwithspecialswirl-inducinghigh-pressureinjectors.Theendresultisafuel-richmixtureinthedirectvicinityofthesparkplug,withextremelyleanair/fuelratiosnearthecylinderwalls.TheD-4canoperatestablywithair/fuelratiosashighas50:1,comparedwiththecompanysexistingindirect-injectedlean-burnenginethatoperateswithmaximumair/fuelratiosofroughly24:1.Toyotasaysacoincidentaladvantageofthehighlystratifiedchargeemployedinthenewengineisacooleraircharge,duetoincreasedfuelvaporization.Thecoolerchargeincreasesvolumetricefficiency,andtheenginealsoisfittedwiththecompanysVVT-i(VariableValveTiming,intelligent)systemtopreciselycontroleachcylindersintakeevent.,Lean-burnenginesareknownfortheircharacteristichighlevelsofNOXemissions.ThecompanysaysthenewD-4usesahighdegreeofexhaustgasrecirculation(EGR)-asmuchas40%whentheengineoperatesinthelean-combustionmode-andthenaturalEGR-likeoperationoftheVVT-isystemtodrasticallyreduceNOXproduction.Thenew3-waycatalystusesastorage/reductiondesigntopurifyoccludedNOXatthestoichiometriclevel-whentheengineoperatesinleanmodes,excessNOXisstoreduntilitcanbecombined/purifiedwithexhaustgasesproducedduringstoichiometricoperation.Thenewenginereliesonpowerful,preciseengine-managementsoftwaretoaccuratelytailorfuel-injectiontimingandduration.Athighloads,suchasduringheavyacceleration,fuelisinjectedearlierinthecompressionstroke,creatingahomogeneousmixtureandoptimumpower.,Crossoverpointsbetweenhomogeneousandstratifiedmixturesproducesemi-stratifiedair/fuelmixtureforsmoothtorquetransition.Torqueproductioninthelow-andmiddle-speedrangesisimprovedby10%overconventionalengines,whilefueleconomyintheJapanese10-15urbanfueleconomytestisimprovedbyasignificant30%orbetter.Moreover,ToyotaclaimsthequickerresponsepresentedbytheDIdesignimproves0to62mph(0-100km/h)andpassingaccelerationtimesby10%.,ElectronicThrottleThrottle-By-WireSomeofthenewestMotronicsystemshaveanelectronicthrottle(alsoknownasathrottle-by-wiresystem).Theelectronicthrottlehasnomechanicallinkbetweentheacceleratorpedalandthethrottlevalve.Instead,asshowninFig.4-3,anacceleratorsensorpicksupyourmovementorpositionoftheacceleratorpedal.Itsignalsthecontrolunitaboutpedalmovement,andthecontrolunitsignalstheservomotoronthethrottleshafttoopen.Theelectronicthrottle(BoschcallsitEGAS)maysoundlikesomethingnoneofusneeds,butithasmanybenefits.,Fig.4-3ElectronicthrottlesendsacceleratorsignaltoMotroniccontrolunitDCmotormovesthrottlevalve,modifiedbyenginetemperature,idlerpm,andmaximumrpm,Thethrottleopeningsignalmaybemodifiedaccordingtoenginerpmandenginetemperature.Itcanprovidesimplifiedcruisecontrol.Itcanalsocontrolminimumrpm,replacingtheidle-speedstabilizer,andcon