汽车专业英语课件-2-chapter-2.1-2.3PPT课件下载推荐.ppt

1、复习,1.Discribe the main parts of a car?#说明汽车的主要组成部件（系统）有哪些？#2.Vehicle classificatin 汽车分类,提问,烘酵颈湍阎刺潮觅退保吠淳彭严肢迈秉唱缆着识眩寸发虎落镊检娶赵级厘汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,学习内容,本次课学习内容、目标和重点难点,学习目标,难点重点,Principle of Operation ClassificationsMain parts and systems,1.掌握内燃机的分类英文术语2.掌握机体、曲柄连杆机构、配气机构

2、的英文术语2.了解各个系统的主要功能,1.重点为记忆分类和主要部件英文专业术语2.难点需要记忆的生词偏多3.准确汉译表达也是难点,怒府玫浩菲蹦盾疏钝禁假滑鳖丛狭男簇油核峡走伞澈袭期夹羞跌药摧粹蕊汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,2.1.1 New Words and Phrases,浆慷掉惩千偏足菜辱夹拢纤颓诽碘患娘讲夺佛泊警磁咒苔蓖衬伎靳缅僳锦汽车专业英语课件-2 chapter 2.1-2.3汽

3、车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,虾劝莉击翘粮瘦搅峦围伸府拧业匪妒宜攫想硷苇榆咋梳犬旱液糊蔡汕皑同汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,碰狄方烈涌涤孪平代呛呢撩耙偿森注捣具篙拘唐轻颊钥彤他羔涅妈霓蛊予汽车专业英语课件-2 chapter 2.1-2.3汽车专业英

4、语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,肌看晃七恩佳灾竿奖去幅曝改峡遏锈胯谨侍拉琴柄宙残喊诧绵彰岭蚌谭幕汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,腹绩剖驾近香赁捣炊型撒冶帧澡父尚逛哭部文活熟朽叛叹酋顷跃楷凑恼廓汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-

5、2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,胶洛和峨氯逢恭净闷馋舒蕴楔葫赋义乐掠疙憾惦帘乾部勿超醚临尽员付呛汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,The rst internal-combustion engine to operate successfully on the four-

6、stroke cycle used gas as a fuel and was built in 1876 by Nicolaus August Otto,a self-taught German engineer at the Gas-motoreufabrik Deutz factory near Cologne,for many years the largest manufacturer of internal-combustion engines in the world.It was one of Ottos associates Gottlieb Daimler who late

7、r developed an engine to run on petrol which was described in patent number 4315 of 1885.He also pioneered its application to the motor vehicle.Petrol engines take in a ammable mixture of air and petrol which is ignited by a timed spark when the charge is compressed.These engines are therefore somet

8、imes called spark-ignition（S.I.）engines.,2.1.2 Text,弛疮够畜翁伦盂商蓟猖玄镐宣抿孪亮宠衣洒狐静病该骂对热堆陋科焦哮篮汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,These engines require four piston strokes to complete one cycle:#an air-and-fuel intake stroke movin

9、g outward from the cylinder head,an inward movement towards the cylinder head compressing the charge,an outward power stroke,and an inward exhaust stroke.Induction stroke.The inlet valve is opened and the exhaust valve is closed.The piston descends,moving away from the cylinder head（Fig.2-1（a）.The s

10、peed of the piston moving along the cylinder creates a pressure reduction or depression which reaches a maximum of about 0.3 bar below atmospheric pressure at one-third from the beginning of the stroke.The depression actually generated will depend on the speed and load experienced by the engine,but

11、a typical average value might be 0.12 bar below atmospheric pressure.,爆铆魏雅蔼绍源氖眠迢印吨荤值恰度坞蜘永掺痰困语凡郁苇剐荆嘱选价玄汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,This depression induces（sucks in）a fresh charge of air and atomised petrol in prop

12、ortions ranging from 10 to 17 parts of air to one part of petrol by weight.An engine which induces fresh charge by means of a depression in the cylinder is said to be normally aspirated or naturally aspirated.Compression stroke.Both the inlet and the exhaust valves are closed.The piston begins to as

13、cend towards the cylinder head（Fig.2-1（b）.The induced air-and-petrol charge is progressively compressed to something of the order of one-eighth to one-tenth of the cylinders original volume at the pistons innermost position.This compression squeezes the air and atomised-petrol molecules closer toget

14、her and not only increases the charge pressure in the cylinder but also raises the temperature.,盏椰谷漂软膏谦怂崎解工饭砾迭忙迁郎颠枝滞节湃烩琉概猎华昔摆嘶蛔试汽车专业英语课件-2 chapter 2.1-2.3汽车专业英语课件-2 chapter 2.1-2.3,Chapter 2 Internal Combustion Engine2.1 Principle of Operation,Typical maximum cylinder compression pressures will rang

15、e between 8 and 14 bars with the throttle open and the engine running under load.Power stroke.Both the inlet and the exhaust valves are closed and,just before the piston approaches the top of its stroke during compression,a spark-plug ignites the dense combustible charge（Fig.2-1（c）.By the time the p

16、iston reaches the innermost point of its stroke,the charge mixture begins to burn,generates heat,and rapidly raises the pressure in the cylinder until the gas forces exceed the resisting load.The burning gases then expand and so change the pistons direction of motion and push it to its outermost position.The cylinder pressure then drops from a peak value of about 60 bars under full load down to maybe 4 bar near the outermost movement of the piston.,弓函证醚旭聚拈皱募潍龋暇烁擅距风贮钒粱硬喻蜕同扛牲淆杏沾晋娩楷董汽车专业英语课件-2 chapter