柴油发动机外文翻译.doc

外文原文The Diesel EngineIn 1892 Rudolf Diesel developed and obtained the German patent for the diesel engine. His goal was to create an engine that was highly efficient. Much more efficient than the gasoline engine that was invented in 1876 and was not very efficient at all, especially at that point in time. There are two main differences between a diesel engine and a gasoline engine: (1) A gasoline engine intakes a mixture of gas and air, compresses it and ignites the mixture with a spark. A diesel engine takes in just air, compresses it and then injects fuel into the compressed air. The heat of the compressed air lights the fuel spontaneously.(2) A gasoline engine compresses at a ratio of 8:1 to 12:1, while a diesel engine compresses at a ratio of 14:1 to as high as 25:1.The higher compression ratio of the diesel engine leads to better efficiency. Gasoline engines use either a carburetor or a fuel injection system to deliver the fuel to the cylinder. With a carburetor the fuel is mixed as it enters the intake manifold, long before it gets to the cylinders. In a fuel injection system the fuel is injected just before the intake stroke at the intake valve.Diesel engines use direct fuel injection (DI), that is to say the diesel fuel is injected directly into the cylinder. The diesel engine has no spark plugs. The air it takes in is compressed and the fuel is injected directly into the cylinder where the heat caused by the air compression ignites the fuel. In the old days this meant that it exploded and expanded very quickly, making a noisy engine. This is why most diesel cars were IDI (indirect injection); the rough behavior was fixed by injecting the fuel into a small pre-combustion chamber that is connected to the cylinder by a narrow passage.This slows down the explosion, as the gasses have to escape from through the narrow passage into the cylinder. This gives a softer bang and a smoother engine, but the gasses have to work harder, which lowers the efficiency a little. However the newer breed of DI engines use other techniques to tame the behavior of the engine, such as two stage injection, electronic control.The injector on a diesel engine is its most complex component and has been the subject of a great deal of development and innovation. On any specific engine it may be located in a variety of places. The injector has to be able to withstand the temperature and pressure inside the cylinder and still deliver the fuel in a fine mist. Getting the mist circulated in the cylinder so that it is evenly distributed is also a problem, so some diesel engines employ special induction valves, pre-combustion chambers or other devices to swirl the air in the combustion chamber or otherwise improve the ignition and combustion process.One major difference between a gas engine and a diesel engine is in the injection process. Most car engines use port injection or a carburetor rather than direct injection. In a car engine all of the fuel is loaded into the cylinder during the intake stroke and then compressed. The compression of the fuel/air mixture limits the compression ratio of the engine. If it compresses the air too much, the fuel/air mixture spontaneously ignites and causes knocking. A diesel compresses only air, so the compression ratio can be much higher. The higher the compression ratio, the more power is generated.In the United States and Canada, diesel engines are most commonly found in trucks and buses. In Europe, where fuel prices fluctuate around $3.00 to $4.00 per gallon, the fuel efficiency of the diesel has made it a popular choice for cars, and most European-market cars are available with a diesel or a turbo-diesel engine.Compared to gasoline-powered vehicles, diesels are more fuel efficient. Diesel engines produce more torque, and they tend to be more durable. They dont need an electric ignition system, which reduces their complexity. However, they also create more noise, they can be difficult to start in extremely cold weather and they sometimes require more frequent routine maintenance than gasoline engines.Most passenger car diesel engines have a glow plug of some type. When a diesel engine is cold, the air compression may not raise the air to a high enough temperature to ignite the fuel. The glow plug is an electric heater that glows red-hot and helps to ignite the fuel when the engine is cold so that the engine can start.The amount of power which an engine can produce is limited by how much fuel it can burn, and the amount of fuel it can burn is limited by the amount of oxygen in the cylinder. The amount of oxygen in the cylinder is limited by the amount of air in the cylinder. So, if more power is wanted then more air is needed, how do we achieve this? Well a large engine has more air, so it can produce more power, or we can compress the air before it gets to the cylinders.This is what a super-charger does; it is a simple air compressor. A super-charger is a mechanically driven compressor run by a belt off the crankshaft.A diesel engine has no spark plugs. Because the air is so compressed and hot at the top of the stroke, the fuel ignites right away when it is injected. This is why a diesel engine is called a Compression Ignition engine and gasoline engines are called Spark Ignition engine. This also means that there are no ignition breakers, ignition coils, distributors and ignition wires to go bad. This allows diesel engines to start no matter if it is dry or rainy and wet.The key to fuel efficiency is to squeeze as much energy as possible out of a given amount of fuel by burning it as completely as possible. Diesel fuel itself has the potential to produce more power than a like quantity of gasoline. Furthermore, high compression ratios help diesels to burn their fuel more completely than gasoline engines. And because diesels always intake a full charge of air while varying the amount of fuel, the air-fuel mixture tends to be a very lean mixture at lower power outputs, which helps burn the fuel more completely.Some modern diesel engines are starting to come out with electronically controlled injection pumps, but the vast majority of them out there have purely mechanical pumps. No electricity is required to make a diesel engine run, except for a simple fuel cut off solenoid so that you can hut the engine down.Turbo-charging a diesel is easier than turbo-charging a gasoline engine. One problem for a gasoline engine is that if the compression ratio is too high, and the pressure in the cylinder gets too high during the inlet stroke, then the fuel/air mixture can start to burn too soon, while the piston is still on the way up. A turbo increases the pressure in the cylinder making this problem worse. With a diesel engine, there is no fuel in the cylinder during the compression stroke, so a turbo can be used to pack as much air in there as desired without causing problems.The process of starting a diesel engine is less affected by temperature. When a gasoline engine is started from cold it needs a lot of fuel to make it run properly. If you do short trips all the time then youll get far below the fuel economy that youd normally get. Since emissions are proportional to the amount of fuel consumed, youll be producing higher pollution levels. Diesel engines are ideal for short journeys because their efficiency is almost as high cold as when they are hot.Diesel engines last a lot longer than gasoline engines. This is because gasoline destroys lubrication and diesel fuel doesnt. Cold start-ups are a real killer for gasoline engines because of all that extra gasoline needed to start a cold engine.A compression ratio of 19:1 to 25:1 gives significant engine braking, but it also makes the engine hard to start. Youll need a good battery, one of very high amperage, and starter motor.Glow plugs are needed. Diesel engines rely on the heat of compressed air to ignite their fuel. When the engine is cold, compression alone may not produce enough heat for the fuel to burn, so most car and truck diesels use glow plugs, electric elements that heat up the cylinder before a cold engine is started These electric heaters are switched on for anywhere from 5 to 10 seconds to make the engine easier to start. They use about 15 amps each (you have one for each cylinder). This is why you need a high amperage battery. For areas with severe winters, a block heater is a good idea. Many diesels have them as standard or optional equipment.Torque is a measure of twisting force, and in the automotive world it translates to the ability to get a load moving.This makes a diesel engine good for towing, trucks and buses, but will never be great in the 0 to 60 ranges.Because of their high compression ratios, diesel engines have to be built with more durable components than gasoline engines. Diesel fuel is a lubricant, and as it is sprayed into the engine during the combustion cycle, it lubricates the cylinder walls. As a result, diesels are subject to less internal wear than gasoline engines, and will usually run many more miles before requiring an overhaul. It can make a car more stable, but will handle and corner differentaly than a gasoline engine. It also makes the steering heavy as well, I would recommend buying a diesel car with power steering.Diesel engines are nosier than gasoline engines. If you open the hood of a gasoline car with the engine running, you know that gasoline engines are fairly quiet. With diesel engines, theres a great deal of mechanical noise, mostly due to the engines high compression ratios and the fuel injection systems. They are even nosier when they are cold.Diesel engines require more frequent routine maintenance than gasoline engines. On the plus side however, normal gasoline engine maintenance such as replacing the spark plugs, rotor and replacing ignition wires are not necessary on a diesel engine. You dont have to worry about an Ignition module or coil going bad. Its simply because a diesel engine has no ignition system.Is a diesel engine right for you? That is something you have to decide based on your needs and driving habits. A diesel powered vehicle will not handle or be as powerful as a gasoline powered vehicle. Diesel fuel is not as readily available as gasoline. I had more than a few times where I was sweating out finding a gas station with diesel. This, however, is starting to change with the increasing number of diesel powered vehicles now on the road. I know I love my diesel and once I adjusted to it, I cant think of driving anything else.中文翻译柴油发动机 节选自：Auto Repair1892年，鲁道夫开发研制出了柴油机，并取得了德国专利。His goal was to create an engine that was highly efficient.他的目标是要创造一个高效率的引擎。早在1876年鲁道夫就发明了一个Much more efficient than the gasoline engine that was invented in 1876 and was not very efficient at all.比汽油发动机更具效率的发动机，然而在那个特定的时间，效果并不是非常明显。Especially at that point in time.柴油发动机和汽油发动机There are two main differences between a diesel engine and a gasoline engine.主要有两个区别：（1）A gasoline engine intakes a mixture of gas and air, compresses it and ignites the mixture with a spark.汽油发动机是在通风口引入汽油和空气的混合气体并将之压缩，同时点燃混合气体产生火花。而A diesel engine takes in just air, compresses it and then injects fuel into the compressed air.柴油机仅仅引入空气，压缩之后，将燃料注入到压缩空气中。The heat of the compressed air lights the fuel spontaneously.压缩空气产生了很高的热量自发的将燃料点燃。（2）A gasoline engine compresses at a ratio of 8:1 to 12:1, while a diesel engine compresses at a ratio of 14:1 to as high as 25:1.汽油发动机压缩比为8：1到12：1 ，而柴油发动机的压缩比为14：1甚至可以高达25：1 。The higher compression ratio of the diesel engine leads to better efficiency.较高的压缩比使柴油机拥有了更好的工作效率。Gasoline engines use either a carburetor or a fuel injection system to deliver the fuel to the cylinder.汽油发动机使用汽化器或燃油注入系统，向气缸释放燃料。在With a carburetor the fuel is mixed as it enters the intake manifold, long before it gets to the cylinders.气化器的作用下燃料在进入通风口的时候就被混合，此时它还远未到达气缸。通常情况下在一个燃料喷射系统中，燃料在通风口阀门打开的之前就应当被注入。In a fuel injection system the fuel is injected just before the intake stroke at the intake valveDiesel engines use direct fuel injection (DI), that is to say the diesel fuel is injected directly into the cylinder.柴油引擎采用直接燃油喷射（DI）形式，这就是说，柴油燃料是被直接注射到气缸的。The diesel engine has no spark plugs.柴油发动机没有火花塞。The air it takes in is compressed and the fuel is injected directly into the cylinder where the heat caused by the air compression ignites the fuel.空气被压缩后产生的热量将直接注射到汽缸的燃料点燃。In the old days this meant that it exploded and expanded very quickly, making a noisy engine.在过去，这意味着气体爆炸并极快的膨胀，所制造出的是一个具有巨大噪音的引擎。This is why most diesel cars were IDI (indirect injection); the rough behavior was fixed by injecting the fuel into a small pre-combustion chamber that is connected to the cylinder by a narrow passage.这就是为什么大多数柴油发动车采用间接的燃油注入方式;大致的固定模式是将燃料注入到一个小预燃室，这个预燃室与气缸通过一条狭窄的通道相联接。This slows down the explosion, as the gasses have to escape from through the narrow passage into the cylinder.这样做减缓了爆炸，同时气体不得不通过狭窄的通道进入气缸。This gives a softer bang and a smoother engine, but the gasses have to work harder, which lowers the efficiency a little.爆炸变得温和，发动机也变得更顺畅，然而气体不能再剧烈碰撞爆发能量，所以系统效率会有所降低。However the newer breed of DI engines use other techniques to tame the behavior of the engine, such as two stage injection, electronic control, and acoustic shrouds and shock absorbing engine mounts to mask the rattle.但新的直接燃油喷射引擎采用其他技术使发动机的行为变得平顺，如两阶段喷射，电子控制等。The injector on a diesel engine is its most complex component and has been the subject of a great deal of development and innovation.喷油器是柴油发动机最复杂的组成部分，并一直得到极大的发展和创新。On any specific engine it may be located in a variety of places.对于不同的发动机，它可能位于不同的地方。The injector has to be able to withstand the temperature and pressure inside the cylinder and still deliver the fuel in a fine mist.喷油器必须能够经受住汽缸内的温度和压力，并依然可以以细雾的形式释放燃料。Getting the mist circulated in the cylinder so that it is evenly distributed is also a problem, so some diesel engines employ special induction valves, pre-combustion chambers or other devices to swirl the air in the combustion chamber or otherwise improve the ignition and combustion process.薄雾在汽缸中流动，如何使它均匀分布也是一个问题，所以有些柴油发动机采用特殊感应阀，预燃室或其他设备使空气在燃烧室涡旋，或以其他方式改善点火和燃烧过程。One major difference between a gas engine and a diesel engine is in the injection process.燃气发动机和柴油发动机的一个主要区别是在于喷射过程。Most car engines use port injection or a carburetor rather than direct injection.大多数汽车发动机使用端口喷射或汽化器喷射，而不是直接喷射。In a car engine all of the fuel is loaded into the cylinder during the intake stroke and then compressed.在一台轿车发动机中所有的燃料被载入汽缸，进入通风口后进行压缩处理。The compression of the fuel/air mixture limits the compression ratio of the engine.压缩的燃料/空气混合气限制了引擎的压缩比。If it compresses the air too much, the fuel/air mixture spontaneously ignites and causes knocking.如果压缩的空气太多，燃料/空气混合物自发地点燃和引起故障音。A diesel compresses only air, so the compression ratio can be much higher.柴油机压缩的只有空气，所以压缩比可以高很多，The higher the compression ratio, the more power is generated.较高的压缩比产生了较强的动力。In the United States and Canada, diesel engines are most commonly found in trucks and buses.在美国和加拿大，柴油发动机是最常见于卡车和巴士。In Europe, where fuel prices fluctuate around $3.00 to $4.00 per gallon, the fuel efficiency of the diesel has made it a popular choice for cars, and most European-market cars are available with a diesel or a turbo-diesel engine.在欧洲，燃料价格约在3.00 4.00欧元每加仑波动，柴油机的燃油效率已使它成为很受欢迎的选择。汽车和大多数欧洲市场的轿车，都可以配备柴油或涡轮柴油发动机。Compared to gasoline-powered vehicles, diesels are more fuel efficient, and they can travel significantly farther on a tank of fuel than their gasoline counterparts.相比汽油动力车，柴油机更省油。Diesel engines produce more torque, and they tend to be more durable.柴油发动机产生更多的扭矩，并且作用往往更持久。They dont need an electric ignition system, which reduces their complexity.它们并不需要一个电子点火系统，从而降低了其复杂性。However, they also create more noise, they can be difficult to start in extremely cold weather and they sometimes require more frequent routine maintenance than gasoline engines.然而，它们制造了更多的噪音，也可能很难在极其寒冷的天气状况下启动，同时相比汽油发动机它们需要更频繁的例行养护。Most passenger car diesel engines have a glow plug of some type.大多数小客车的柴油引擎有一个类型不同的电热塞。When a diesel engine is cold, the air compression may not raise the air to a high enough temperature to ignite the fuel.当柴油机受冷，空气压缩可能不会使空气到达一个足够高的温度而引燃燃料。The glow plug is an electric heater that glows red-hot and helps to ignite the fuel when the engine is cold so that the engine can start这个发热塞是一个可以产生炙热的电子发热器，有助于引燃燃料，当发动机受冷时也能使发动机启动。The amount of power which an engine can produce is limited by how much fuel it can burn, and the amount of fuel it can burn is limited by the amount of oxygen in the cylinder.发动机产生的动力大小受到燃料燃烧量的限制，燃料燃烧量又受到汽缸中氧气含量的限制。So, if more power is wanted then more air is needed, how do we achieve this?所以，如果需要更多的动力，则需要更多空气，我们如何做到这一点？Well a large engine has more air, so it can produce more power, or we can compress the air before it gets to the cylinders.那么一个大型发动机容纳了更多的空气，因此它能够产生更多的动力，或者我们可以把空气在进入气缸之前就进行压缩。This is what a super-charger or turbo-charger does; they are a simple air compressor.这就是增压充电器做的，它是一个简单的空气压缩机，由A super-charger is a mechanically driven compressor run by a belt off the crankshaft.一个机械驱动的压缩机通过机轴带动运行的。A turbo-charger is made to spin by blowing exhaust gasses over a turbine on one end of a shaft and compresses air with a turbine at the other end of the shaft.A diesel engine has no spark plugs.柴油机引擎没有火星塞。Because the air is so compressed and hot at the top of the stroke, the fuel ignites right away when it is injected.因为空气在冲程的顶部被压缩并释放巨大的热，当燃料被注入时就马上被点燃了。This is why a diesel engine is called a Compression Ignition engine and gasoline engines are called Spark Ignition engine.这就是为什么柴油机是一种被称为“压缩点火”的发动机，而汽油发动机则被称为“火花点火引擎”。This also means that there are no ignition breakers, ignition coils, distributors and ignition wires to go bad.这也意味着不存在点火开关，点火线圈，点火导线不能正常工作的问题。This allows diesel engines to start no matter if it is dry or rainy and wet.这使得柴油发动机无论在干燥、多雨或潮湿的环境中都能正常运行。The key to fue