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1、Chapter Two Automobile Engines2.3 What Is Crankshaft and Flywheel2.4 How Fuel Injection Systems Work2.5 How Car Cooling Systems Work背景知识背景知识 生词生词译文及评析译文及评析 2.3 What Is Crankshaft and Flywheel作业作业背景知识背景知识Flywheel is a heavy wheel attached to the shaft of an engine to keep its speed nearly constant. 生
2、词生词crankshaft n.曲轴castn.铸件forging n.锻件alloy n.合金considerable adj.相当的，可观的mechanical adj.机械的strength n.强度downward adj.向下的thrust n.v.插，插入excessive a.过多的，过度的distortion n.扭曲eliminate v.淘汰，剔除生词生词undue a.不恰当的，过分的vibration n.振动，颤动offset a.偏移的counterweight n.平衡物bearings n.轴承sprocket n.扣连齿(链轮上与链条结合的齿)camshaft
3、 n.凸轮轴damper n.减振器belt n.皮带pulley n.滑轮生词生词generator n.产生器，发电机flywheel n.飞轮impulse n.脉冲overlap n.v.重叠，重复重叠，重复combat v.努力纠正tendency n.倾向comparativelyad.比较地inertia n.惯性译文及评析译文及评析 CramlshaftThe crankshaft is a one-piece casting or forging of heat treated alloy steel of considerable mechanical strength.
4、本句内容的叙述层次与汉语基本一致，本句内容的叙述层次与汉语基本一致，采用采用“顺译法顺译法”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 曲轴曲轴曲曲轴是由合金钢整体铸造或锻造，经过热处理，具有一定轴是由合金钢整体铸造或锻造，经过热处理，具有一定的机械强度的机械强度译文及评析译文及评析 The crankshaft must be strong enough to take the downward thrusts of the pistons during the power strokes without exc
5、essive distortion. 注意翻译的灵活性，进行适当的词性转换。注意翻译的灵活性，进行适当的词性转换。“strong”strong”是是形容词，意思是形容词，意思是“强度高的强度高的”，翻译成，翻译成“具有足够的强度具有足够的强度”比较通顺。同样，不妨把比较通顺。同样，不妨把“without excessive without excessive distortion”distortion”翻译成翻译成“不会产生过度的扭曲不会产生过度的扭曲”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 曲轴必须具曲轴必须
6、具有足够的强度有足够的强度，以承受在作功行程中活塞的向，以承受在作功行程中活塞的向下运动所产生的冲力，而下运动所产生的冲力，而不会产生过度的扭曲。不会产生过度的扭曲。译文及评析译文及评析 In addition, the crankshaft must be carefully balanced to eliminate undue vibration resulting from the weight of the offset cranks. To provide balance, crankshafts have counterweights opposite the cranks. C
7、rankshafts have drilled oil passages through which oil can flow from the main to the connecting-rod bearings.opposite the cranksopposite the cranks不能翻译成不能翻译成“与曲轴相反的与曲轴相反的”，而，而是应该是是应该是“与曲柄偏心相平衡的与曲柄偏心相平衡的”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 另外，曲轴必须仔细地平衡，以避免因曲柄重心偏移而引另外，曲轴必须仔细地
8、平衡，以避免因曲柄重心偏移而引起剧烈振动。为了保持平衡，曲轴上有起剧烈振动。为了保持平衡，曲轴上有与曲柄偏心相平衡与曲柄偏心相平衡的的配重。曲轴上还钻有油道，使润滑油可以从主轴承流到配重。曲轴上还钻有油道，使润滑油可以从主轴承流到连杆轴承上。连杆轴承上。译文及评析译文及评析 The front end of the crankshaft carries three devices, the gear or sprocket that drives the camshaft, the vibration damper, and the fan belt pulley. The pulley dr
9、ives the engine fan, water pump, and generator with a V belt.曲轴带轮和减振器必须作为一个总成进行平衡。曲轴带轮和减振器必须作为一个总成进行平衡。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 在曲轴的前段有三个装置：驱动凸轮轴的齿轮或链轮、减在曲轴的前段有三个装置：驱动凸轮轴的齿轮或链轮、减震器和风扇皮带轮。皮带轮通过震器和风扇皮带轮。皮带轮通过V V型皮带驱动发动机风扇，型皮带驱动发动机风扇，水泵和发电机。水泵和发电机。译文及评析译文及评析 Flywheel
10、The flow of power from the engine cylinders is not smooth. Although the power impulses overlap (on six- and eight-cylinder engines), there are times when more power is being delivered than at other times. This tends to make the crankshaft speed up and then slow down. timestimes翻译为翻译为“有些时候有些时候”； spee
11、d up and then slow speed up and then slow down.“down.“运转速度忽快忽慢运转速度忽快忽慢”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 飞轮飞轮发发动机气缸所产生的动力不均匀的。尽管在六缸或八缸发动机动机气缸所产生的动力不均匀的。尽管在六缸或八缸发动机中，动力冲击重叠发生，但是有时产生的动力会大些。这会使中，动力冲击重叠发生，但是有时产生的动力会大些。这会使曲轴的曲轴的运转速度忽快忽慢运转速度忽快忽慢。However, the flywheel combats th
12、e tendency. The flywheel is a comparatively heavy wheel bolted to the rear end of the crankshaft. The inertia of the flywheel tends to keep it turning at constant speed. Thus, the flywheel absorbs energy as the crankshaft tries to speed up and gives back energy as the crankshaft tries to slow down.
13、“absorbs energy”absorbs energy”、 “ “ gives back energy”gives back energy”、“speed speed up ”up ”、 “ “slow down”slow down”为为“吸收能量吸收能量”“”“释放能量释放能量”“”“加加速速”“”“减速减速”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 然而飞轮可以克服这种倾向。飞轮是一个很重的轮子，用螺栓然而飞轮可以克服这种倾向。飞轮是一个很重的轮子，用螺栓固定在曲轴的后端。飞轮的惯性使飞轮保持恒速运动。
14、这样，固定在曲轴的后端。飞轮的惯性使飞轮保持恒速运动。这样，飞轮在曲轴加速时把能量贮存起来，当曲轴速度减慢时再释放飞轮在曲轴加速时把能量贮存起来，当曲轴速度减慢时再释放出出来。来。译文及评析译文及评析 In effect, the flywheel absorbs power from the engine during the power，stroke (or speedup time) and then gives it back to the engine during the other three strokes (or slow down time ) of the cycle.i
15、n effect = in fact in effect = in fact 事实上事实上事事实上，飞轮在做功行程（或加速过程）中贮存动能，而在其实上，飞轮在做功行程（或加速过程）中贮存动能，而在其它三个行程（或减速行程）中，把动能释放出来。它三个行程（或减速行程）中，把动能释放出来。译文及评析译文及评析 crankshaft: n. 曲轴, 曲柄轴整体式曲轴 one-piece crankshaft 组合式曲轴 assembled crankshaft 曲轴前端 crankshaft front end 曲轴主轴颈 crankshaft main journal 曲轴止推轴承 cranksh
16、aft thrust bearing 曲轴油道 crankshaft oil passage 曲柄 crank 曲柄臂 crank arm 曲柄销 crank pin 汽车英文缩写字母CC 发动机排量单位发动机排量单位:毫升毫升L(Lengtn) 气缸排列法，代表直列。气缸排列法，代表直列。L4，直列，直列4缸缸V（6、8、12） 气缸排列成气缸排列成“V”字型，字型，“6、8、12”表示气缸数表示气缸数量量DOHC 双顶置凸轮轴。双顶置凸轮轴。OHC，顶置凸轮轴。，顶置凸轮轴。EFI 燃油喷射燃油喷射The engine acts as the power unit. The interna
17、l combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine :gasoline ( also called a spark-ignition engine) and diesel ( also called a compression-ignition engine ). Both engines are called heat engines; the burning f
18、uel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the transmission.发动机充当动力装置。内燃机是最常见的：它通过液体燃料在发动机汽缸里燃烧获得动力。发动机有两种类型:汽油机 (也称点燃式发动机)和柴油机(也称压燃式发动机)。这两种发动机都叫做热机；燃料在气缸内燃烧产生的高温高压气体推动曲轴旋转而传递动力。作业作业P23. Translate following ex
19、pressions into English . Translate following sentences into Chinese 背景知识背景知识 生词生词译文及评析译文及评析 2.4 How Fuel Injection Systems Work作业作业背景知识背景知识生词生词fuel n.燃料injection n.喷射injector n.喷油器electronically adv.电子地control v.控制,valve n.电子管supply n.供给 pressurize v.给加压pump n.泵energize v.开始工作时electromagnet n.电磁石plu
20、nger n.活塞squirt v.喷出nozzle n.管口, 喷嘴design v.设计生词生词atomize vt.将.喷成雾状mist n.薄雾burn v.燃烧easily adv容易地, 不费力地amount n.总计, 等于determine v.决定 pulse n.脉搏, 脉冲width n.宽度mount v.安装 intake n.入口, 进气manifold n.歧管spray vt.喷射, 喷溅directly adv直接地, 立即equip vt.装备sensor n.传感器译文及评析译文及评析 A fuel injector is nothing but an e
21、lectronically controlled valve. It is supplied with pressurized fuel by the fuel pump in your car, and it is capable of opening and closing many times per second. “be nothing but” “be nothing but” “不是别的正是不是别的正是”过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 燃油喷射器不是别的而是一个电子控制阀。它由车内的燃燃油喷
22、射器不是别的而是一个电子控制阀。它由车内的燃油泵提供高压油，而且，该喷射器一秒钟内能数次开合。油泵提供高压油，而且，该喷射器一秒钟内能数次开合。译文及评析译文及评析 When the injector is energized, an electromagnet moves a plunger that opens the valve, allowing the pressurized fuel to squirt out through a tiny nozzle. The nozzle is designed to atomize the fuel - to make as fine a
23、mist as possible so that it can burn easily.句子较长，可以采用拆句顺译，拆成短句，句子较长，可以采用拆句顺译，拆成短句，并符合原英文顺序。并符合原英文顺序。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 喷射器工作时，由电磁铁移动柱塞打开阀门，经细小喷嘴喷射器工作时，由电磁铁移动柱塞打开阀门，经细小喷嘴射出高压油。这种专门设计的喷嘴能射出雾化汽油射出高压油。这种专门设计的喷嘴能射出雾化汽油使使燃油尽可能雾化成细小颗粒，故便于燃烧。燃油尽可能雾化成细小颗粒，故便于燃烧。 译文及评
24、析译文及评析 The amount of fuel supplied to the engine is determined by the amount of time the fuel injector stays open. This is called the pulse width, and it is controlled by the ECU.“sthsth is determined by is determined by sthsth” “” “所决定所决定”过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。
25、 发动机的供油量是由喷射器阀门开启的时间长短所决定的，发动机的供油量是由喷射器阀门开启的时间长短所决定的，这就是脉宽，由这就是脉宽，由ECUECU控制。控制。译文及评析译文及评析 The injectors are mounted in the intake manifold so that they spray fuel directly at the intake valves. A pipe called the fuel rail supplies pressurized fuel to all of the injectors.“are mounted in”“ are mounte
26、d in”“ 安装在安装在”。过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 喷油器就安装在进气歧管上，燃油直接射入进气门，油管喷油器就安装在进气歧管上，燃油直接射入进气门，油管提供喷射器所需的高压油。提供喷射器所需的高压油。气门气门喷油器喷油器输油管输油管进气支管进气支管译文及评析译文及评析 In order to provide the right amount of fuel, the engine control unit is equipped with a whole lot of sensors. “be
27、be equipped with”equipped with” “配备配备”过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 为了供油准确，发动机控制系统还配备了一整套传感器。为了供油准确，发动机控制系统还配备了一整套传感器。Fuel n. 燃料， vt. 加燃料, 供以燃料 vi. 得到燃料fuel oil 燃料油fuel rate 燃料率fuel system 燃油系统jet fuel 喷气燃料A fuel pump; fuel tanks. 燃料泵；使用燃料的坦克pollution-free fuel 无污染燃料Wh
28、en a gas is heated it tries to expand if this expansion is resisted then a high pressure is built up which in turn creates a large force.A mixture of petrol and air compressed in a cylinder makes an explosive gas. When the gas is ignited the pressure moves the piston towards the open end of the cyli
29、nder.当一种气体被加热时，它会不断膨胀当一种气体被加热时，它会不断膨胀 如果这膨胀受到抵抗那么高压会如果这膨胀受到抵抗那么高压会增加来产生巨大的力量。增加来产生巨大的力量。汽油和空气的混合物在一个汽缸内压缩成一种可燃气体。当气体被点燃时，汽油和空气的混合物在一个汽缸内压缩成一种可燃气体。当气体被点燃时，压力推动活塞在汽缸里做往复运动。压力推动活塞在汽缸里做往复运动。作业作业P27. Translate following expressions into English . Translate following sentences into English背景知识背景知识 生词生词译文及
30、评析译文及评析 2.5 How Car Cooling Systems Work作业作业背景知识背景知识冷却系功用 使发动机得到适度的冷却，并保持其在最适宜地温度范围内工作。 生词生词cool v.冷却gasoline n.汽油improve v.改善, 提高efficient a.有效率的mechanical a.机械的convert v.转变freeway n.通道dissipate v.驱散average-size n.平均尺寸overheating a.过热component n.零件emit v.散发pollution n.污染constant a.n.不变的, 恒量译文及评析译文及
31、评析 Although gasoline engines have improved a lot, they are still not very efficient at turning chemical energy into mechanical power. Most of the energy in the gasoline (perhaps 70%) is converted into heat, and it is the job of the cooling system to take care of that heat.“it is it is to” to” itit 是
32、形式主语是形式主语, , 真正的主语是不定式真正的主语是不定式 “to to ”“take care of” “take care of” “照顾照顾, , 负责负责”过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 虽然汽油发动机改进了许多，但是，把化学能量转变为机械能量虽然汽油发动机改进了许多，但是，把化学能量转变为机械能量过程中，发动机的效率仍然不高。汽油的大部分能量（大概过程中，发动机的效率仍然不高。汽油的大部分能量（大概70%70%）变成了热能。而冷却系统的任务就是处理这些热能变成了热能。而冷却系统的任务就是处理
33、这些热能译文及评析译文及评析 In fact, the cooling system on a car driving down the freeway dissipates enough heat to heat two average-sized houses! The primary job of the cooling system is to keep the engine from overheating by transferring this heat to the air, but the cooling system also has several other impor
34、tant jobs.keep keep from from 阻止阻止( (某事某事) )事实上汽车在高速公路行驶时事实上汽车在高速公路行驶时, , 其冷却系统散发大量的热量，都其冷却系统散发大量的热量，都足以给两间一般性的房子供暖了足以给两间一般性的房子供暖了! ! 冷却系统的主要任务是将热传冷却系统的主要任务是将热传给大气，阻止发动机过热；此外，冷却系统还有其它重要任务。给大气，阻止发动机过热；此外，冷却系统还有其它重要任务。译文及评析译文及评析 The engine in your car runs best at a fairly high temperature. When the e
35、ngine is cold, components wear out faster, and the engine is less efficient and emits more pollution. So another important job of the cooling system is to allow the engine to heat up as quickly as possible, and then to keep the engine at a constant temperature.the engine is less efficient and emits
36、more pollution.the engine is less efficient and emits more pollution.如如果直译就变成果直译就变成“比较不有效率比较不有效率”“”“较多的污染较多的污染”，显然，不符合，显然，不符合习惯，应该调整为习惯，应该调整为“效率下降，效率低效率下降，效率低”，“ “ 废气排放严重废气排放严重”。as quickly as possible as quickly as possible 尽快尽快过了一会，小男孩不哭了，睁开眼睛，过了一会，小男孩不哭了，睁开眼睛，用询问的目光看着越南护士。用询问的目光看着越南护士。 你的汽车发动机在高温下
37、处于最佳运转状态。而当发动机冷机状你的汽车发动机在高温下处于最佳运转状态。而当发动机冷机状态时就磨损得很快，从而导致发动机效率下降，废气排放严重。态时就磨损得很快，从而导致发动机效率下降，废气排放严重。正因如此，冷却系统还有一个任务，就是让发动机迅速预热，以正因如此，冷却系统还有一个任务，就是让发动机迅速预热，以及让发动机保持恒定的温度。及让发动机保持恒定的温度。Cooling n. 冷却 a. 冷却的engine cooling 发动机冷却water cooling 水的冷却cooling water system 冷却水系统space cooling technique 空间致冷技术rec
38、irculating cooling water system 循环冷却水系统cooling system of internal combustion engine 内燃机冷却系统我们讲述了英语长句的逆序法、顺序法和分句我们讲述了英语长句的逆序法、顺序法和分句法法, 事实上事实上,在翻译一个英语长句时在翻译一个英语长句时, 并不只是单并不只是单纯地使用一种翻译方法纯地使用一种翻译方法, 而是要求我们把各种方而是要求我们把各种方法综合使用法综合使用。Grammar: 长句的翻译（二）长句的翻译（二） Pure science has been subdivided into physical
39、science, which deals with the facts and relations of the physical world, and the biological sciences, which investigated the history and workings of life on this planet.理论科学分为自然科学和生物科学。前者研究理论科学分为自然科学和生物科学。前者研究自然界的各种事物和相互关系，而后者则探讨自然界的各种事物和相互关系，而后者则探讨地球上的生物的发展历史和活动。地球上的生物的发展历史和活动。分译法分译法physical scienc
40、e和 biological science是subdivided into的并列宾语，但这两个宾语的后面都带有长而复杂的定语，如果按顺序译会显得层次混乱，不易理解。汉语中改译，即先将两个并列成分译出，然后在分别加以论述，使语篇的眉目更加清晰，逻辑性也较强，更符合汉语的表达习惯。Answer the following questions in English (用英语回答问题)What is most of the energy in the gasoline converted into?Most of the energy in the gasoline (perhaps 70%) is
41、converted into heatWhat is the primary job of the cooling system?To take care of that heat.What happen to components when the engine is cold?When the engine is cold, components wear out faster.Why is it another job of the cooling system to allow the engine to heat up?Because the engine in your car runs best at a fairly high temperature.作业作业P31. Translate following expressions into English