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1、WuhanInstituteofShipbuildingTechnologyPowerEngineeringDepartmentLuobinLesson12MEEngines第12课ME柴油机Theintroductionoftheelectronicallycontrolledcamshaft-lesslowspeeddieselengines,whichisnowgainingmomentum,isamilestoneindieseltechnologythatdeservesaplaceinhistorylikeRu
2、dolfDiesel'sfirstengineinAugsburg,the1912motorvesselSelandia,theintroductionofturbochargingontwo-strokedieselsin1954,andthefirstSCR(SelectiveCatalyticNoxReduction)systemsonshipsin1989.正在得到发展的电控无凸轮轴低速柴油机的应用,是值得载入史册的柴油机技术史上的里程碑,如同鲁道夫·狄塞尔在奥斯伯格的第一台发动机,1912年第一艘柴油机动力轮船塞
3、拉迪亚号,1954年透平增压首次应用在二冲程柴油机上,1989年选择催化还原氮氧化物减排系统在船上首次应用。Camshaft-controlleddieselengineshavebeenthestateofthearteversincethebirthofreciprocatingmachineryandhavebeenrefinedanddevelopedeversince.凸轮轴控制式柴油机是自从往复式机器诞生以来就采用的工艺形式,并不断地得到优化和发展。However,amechanicalcamisfixedon
4、cemadeand,inspiteofvariousmechanicalandhydraulicadd-ondeviceslikeVIT.然而机械凸轮一旦安装就固定在那儿,尽管有各种机械和液压的外加装置,如可变喷油定时(VIT)机构等,定时控制的可调性仍然是受机械凸轮限制的。etc.,timingcontrolpossibilitiesarelimitedwithmechanicalcams.Notleastfuelinjectionpressurecontrolandvariationovertheloadrangeha
5、velimitationswithacamcontrolledengine.凸轮控制式柴油机受燃油喷射压力的控制及其在一定负荷范围内变化的限制。Therefore,themainpurposeofchangingtoelectroniccontrolistoensurefuelinjectiontimingandrate,aswellastheexhaustvalvetimingandoperation,exactlywhenandasdesired.因此,(由机械式)改为电控的主要目的是保证喷油正时、喷油率以及排气阀正时
6、和运行都能按需准时。Especiallywithrespecttothefuelinjectionrate,thecontrolsystemhasbeensodesignedthatitispossibletomaintainaratherhighinjectionpressurealsoatlowload,withoutthelimitationfromthecamshaft-controlledengine,wherethiswouldresultintoohighpressureathighload.特别是关于喷油率
7、,(无凸轮轴)控制系统的设计使得即使在低负荷时也可能保持相当高的喷射压力,而不受到凸轮轴控制柴油机的类似限制,因为凸轮轴控制柴油机会导致高负荷时喷油压力过高。Bothcamangle,inclinationandlengthareelectronicallyvariable.“凸轮角度、曲率和作用长度”都是电子可调的。Inaddition,theMEenginefeatureselectroniccontrolofthecylinderlubeoilfeed,byhavingourproprietaryAlphaLubri
8、catorsintegratedinthesystem.此外,通过系统内安装独有的Alpha注油器,ME型机器还具有电控气缸油供油的特点。WiththeAlphaLubricationsystem,about0.3g/bhphcyl.Oilcanbesaved,comparedwithengineswi