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英语翻译For the lay individual,the labyrinth of hoses,wire harne

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英语翻译
For the lay individual,the labyrinth of hoses,wire harnesses,manifolds and tubing beneath a car hood might appear intimidating.But when it comes to the gasoline engine,just know this:It needs fuel,air (oxygen,to be precise) and spark in order to operate.
The two most critical differences between a direct injection engine and a standard gasoline engine are how they deliver fuel and how the fuel mixes with incoming air.These basic premises make a tremendous difference in an engine's overall efficiency.
Before we look inside the direct injection engine,let's view a quick second in the life of a standard gasoline engine (for a more complete look at the gasoline engine,check out How Car Engines Work).First,the fuel travels via pump from the fuel tank,through the fuel line and into fuel injectors that are mounted into the engine.The injectors spray gasoline into the air intake manifold,where fuel and air mix together into a fine mist.At precisely timed intervals,intake valves open,corresponding to the different cylinders of the engine.As a cylinder's intake valve opens,a piston in that cylinder descends,sucking the fuel-air mist from the air manifold above into the chamber below.As the piston ascends once more,it squeezes (compresses) the fuel-air mix until it is nearly nine times as dense as it was to begin with.Then,that cylinder's designated spark plug fires,igniting the chamber into a high-pressure,high-energy explosion.This little bang pushes the piston back down with tremendous force,causing it to turn the crankshaft and ultimately send power to the wheels.
Got that?Pretty complicated,huh?It works,but from an engineering standpoint,it leaves much to be desired,and it's pretty wasteful.
With a direct injection engine,however,the fuel gets to skip a step and add a bit of efficiency.Instead of hanging out in the air intake manifold,fuel is squirted directly into the combustion chamber.With an assist from modern engine management computers,the fuel gets burned right where it's needed,when it's needed [source:Fueleconomy.gov].
对于一辆整车,内部所配备的部件多得惊人,包括迷宫一般的软管、线束和进排气歧管.但是对于汽油发动机来说,我们只需要了解这样一些知识:它需要燃料、空气(精确的氧气)和用于点火的火花.
直喷发动机和普通发动机最关键的差异在于它们的输油方式和油气混合方式.这些基本的前提使发动机整体效率产生巨大的差异.
在我们研究直喷发动机内部构造之前,让我们先来快速了解一下普通发动机的工作过程:首先,燃油从油箱经油泵进入输油管,然后进入喷油器并喷射入发动机.喷油器把汽油喷到进气歧管,在这里在燃料和空气混合成细雾.在精确的时间间隔中,进气门打开,混合气进入相应的发动机的气缸.在进气门开启时,活塞开始向下运动,将混合气从进气歧管吸入燃烧室.活塞向上运动时,几乎能把混合气压缩到最开始的九分之一.然后,该气缸对应的火花塞点火,点燃了气缸内的混合气,混合气剧烈燃烧产生高温高压.这个小爆炸产生的巨大能量推动活塞向下运动,使其推动曲轴转动并最终将动力传递到车轮
你明白了吗?有一些复杂是吧?它确实能够完成工作,但是从工程的角度来看,它有很多不足并且相当的浪费.
然而,对于直喷发动机,燃油输送跳过了一个步骤,并且还提高了效率.它不是将汽油喷射到进气歧管中,而是直接把汽油喷进燃烧室内.在现代发动机管理电脑的帮助下,燃料在最适合的时候被点燃.【来源:某政府网站】
哎,这么简单的问题扯这么多,眼睛都花了!
纯手敲,望采纳~