Lesson 1 Types of Diesel Engine

《Lesson 1 Types of Diesel Engine》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Lesson1TypesofDieselEngine第1课柴油机的种类1.Theinventionofthedieselenginein1892hasbeenattributedtoRudolfDiesel,aGermanmechanicalengineerandinventor.Sincethendieselengineshaveplayedanimportantroleintheshippingindustrybecauseoftheirimprovedengineefficienciesanddesignscomparedtootherformsofp

2、ropulsionsuchassteamorgasturbines.Dieselenginesareknownbythenameofcompressionignitionenginesduetotechnicalreasons.Thereareseveralwaysofclassificationofdieselenginesbasedonvariousparameters.Accordingtotheirspeeds,dieselenginesmaybedividedintothreetypes:slowspeed,mediumspeedandhighsp

3、eeddieselengines.1.1892年柴油机的问世归功于德国机械工程师、发明家鲁道夫·狄塞尔。自此，由于与其他形式的推进装置比如蒸汽机或燃气轮机相比，柴油机在效率和设计上更具优势，在航运业发挥了很重要的作用。川出于技术原因，柴油机也叫压燃机。基于不同的参数柴油机有若干种分类方法。柴油机根据速度可分三类:低速、中速和高速柴油机。SlowSpeedDieselEngines低速柴油机2.Slowspeeddieselenginesarelarge,especiallytall,andheavyandoperateonthetwo-strokecycle

4、.Theyarethelargestdieselengineseverbuilt.Enginepowerupto100,000kWisavailablefromasingleengine.Theyaretalltoallowforlongstrokeswhichimproveengineefficiency.Thelargephysicalsizeoftheengineandcomponentsleadstoslowrotationalspeedwithspeedsupto300r/minconsideredtobeslow.Forequivalentpow

5、eroutput,thetwo-strokedieselengineissignificantlylighterthanthefour-strokeone.Thisismostapparentforlargepowerrequirementswherethetwo-strokeengineproducesmuchmorepowerforthesameweight.2.低速柴油机体积大，高度特别高，而且重量大，以二冲程循环运转。这是迄今为止建造出的最大型的柴油机。单独一台发动机就能提供高达100000kW的功率。这类柴油机之所以高是为了容许长冲程，从而提高发动

6、机的效率。大体积的柴油机和部件使得转速较慢，为300r/min，这被视为低速。对于相同的输出功率，二冲程柴油机明显轻于四冲程柴油机。这一点对于满足大功率的需求是非常明显的，相同重量时二冲程柴油机能产生更大的功率。3.Large,slowspeed,two-strokemarinedieselenginesoffertheadvantagesof•burningpoorerquality,cheaperfuel;•providinglargepowerfromasingle,lesscomplicatedmachinecomprisingfewerindivi

7、dualcylindersandmovingparts•havingalowrotationalspeedallowingthemtobedirectlycoupledtothepropellerandremovingtheneedforgearboxes;and•beingreversibleandthuseliminatingtheneedforreversinggearorcontrollablepitchpropellers.3.大型低速二冲程船用柴油机有以下优点:·燃烧质量较差、价格低廉的燃料;··由单台不太复杂的发动机提供大功率，分段气缸和运动部

8、件数量较少;·具有低转速，能够直接连接螺旋桨，不需要