四个冲程及日常英语 中英翻译

1、The Four Stroke of Internal Combustion EngineToday, internal combustion engines in cars, trucks, motorcycles, aircraft, construction machinery and many others, most commonly use a four-stroke（冲程） cycle. The four strokes refer to intake, compression, combustion (power), and exhaust strokes that occur

2、 during two crankshaft rotations per working cycle of the gasoline engine and diesel engine. A less technical description of the four-stroke cycle is, "Suck, Squeeze, Bang, Blow"今天，内燃机汽车、 卡车、 摩托车、 飞机、 工程机械和许多其他人最常使用 four-stroke(冲程) 周期。四个笔画参考摄入量、 压缩、 燃烧 （电源），并在每个工作周期的柴油机与汽油机的两个曲轴旋转过程中发生的排气描

3、边。四冲程循环的不少技术说明的是，"吸，挤压，爆炸，打击The cycle begins at top dead center (TDC上止点), when the piston is farthest away from the axis of the crankshaft. A stroke refers to the full travel of the piston from Top Dead Center (TDC) to Bottom Dead Center (BDC下止点). (Dead centre正中心)周期开始顶死中心 （TDC上止点），当活塞最远距离的曲轴轴。脑

4、卒中从顶部死中心 （贸发局） 到底部死中心 （BDC下止点） 是指整个行程的活塞。(死 centre正中心)Stroke 1 of 4 "Suck": On the intake or induction stroke of the piston , the piston descends from the top of the cylinder to the bottom of the cylinder, reducing the pressure inside the cylinder. A mixture of fuel and air is forced by at

5、mospheric (or greater) pressure into the cylinder through the intake port. The intake valve(s) then close.活塞摄入量或感应脑卒中，活塞从顶部的气缸降落到底部的气瓶，减少气缸内的压力。燃料与空气的混合物的大气 （或更高版本） 的压力被迫通过进气道气缸。摄入 valve(s) 然后关闭。Stroke 2 of 4 "Squeeze": With both intake and exhaust valves closed, the piston returns to the

6、top of the cylinder compressing the fuel-air mixture. This is known as the compression stroke. 4 挤压油行程 2： 进气和排气阀关闭，活塞返回到压缩燃料-空气混合物的气瓶的顶部。这被称为压缩行程。Stroke 3 of 4 "Bang": While the piston is at or close to Top Dead Center, the compressed airfuel mixture is ignited, usually by a spark plug (fo

7、r a gasoline or Otto cycle engine(等容循环发动机) or by the heat and pressure of compression (for a diesel cycle or compression ignition engine（压燃机）). The resulting massive pressure from the combustion of the compressed fuel-air mixture drives the piston back down toward bottom dead center with tremendous

8、force. This is known as the power stroke, which is the main source of the engine's torque and power.虽然活塞处于或接近顶死中心，压缩的 airfuel 混合是，通常火花点火式 (汽油或奥托循环 engine(等容循环发动机) 或热量和压力的压缩 （柴油周期或压缩点火的 engine(压燃机)。从燃烧的压缩的燃料-空气混合物产生巨大压力降低活塞回向底部死中心以巨大的力量。这被称为电源描边，即该引擎的扭矩和功率的主要来源。Stroke 4 of 4 "Blow": Dur

9、ing the exhaust stroke, the piston once again returns to top dead center while the exhaust valve is open. This action evacuates the products of combustion from the cylinder by pushing the spent fuel-air mixture through the exhaust valve(s).在排气冲程，活塞再次返回到上止点排气门处于打开状态时。此操作从缸撤出燃烧产物，通过推动乏的燃料-空气混合物通过排气倾覆。

10、1 LightLight, just like radio waves, X-rays and so on, is a kind of electromagnetic waves. The velocity of the electromagnetic waves in vacuum is 300,000km/sec. Nothing in the world travels faster than the electromagnetic waves. But their wave lengths and frequencies are different. The wave length o

11、f light is shorter than that of radio waves and longer than that of X-rays. But the frequency of light is just the other way around, it is greater than that of radio waves and smaller than that of X-rays. The sun is the largest source of light. We know that life on the earth depends on the heat of t

12、he sun. but the light of the sun is as necessary to life as its heat. Another important source of light is produced by electric sparks in tubes which contain special gases. That is known as indirect light. The light we see directly from the source of light, such as the sun, in known as direct light.

13、 It is from the practice of production and scientific experimentation that we have got to know light travels in space at a speed of about 300,000 kilometres per second. This figure has been proved correct again and again through practice, through only practice, in a number of different ways. Some id

14、eas of this tremendous speed may be got from the tact that while pronounce its name “light” it may travel a distance equal to eight times the worlds circumference. One of the most important facts about light is that is travels in straight lines. If this is not the case it would be impossible accurat

15、ely to aim at an object through the sight of a rifle to the eye. However, this does not in the least mean that the light from a lamp travels only in one direction. But as a matter of fact it scatters. Besides, traveling in straight lines light cannot turn by itself and that is why there are shadows.

16、 If on the contrary light could of itself pass round an object there would be no shadows at all. 2 Heat conductionNo doubt you have burned your hand on a hot oven or other hot metal object. No doubt you have walked barefoot on a pavement that the sun had made very hot. If so, some of the heat passes

17、 by conduction into your hand or foot. There common experiences illustrate an important principle: whenever one body touches another, heat always passes by conduction from the warmer to the colder. Thus one body loses heat and becomes colder, while the other gains heat and becomes warmer. Finally, t

18、hey both reach the same temperature. All bodies of matter conduct heat to some degree. But many solids conduct heat better that do liquids, and liquids better than gases. Of solids metal conduct heat most quickly. They are the best heat conductors. Substances such as wood, plastics, and paper conduc

19、t heat slowly. They are therefore poor conductors, or good insulators of heat. That is why hands of some ovens and pots are made of woods and plastics and not of metals. 3 How Heat TravelsThere are a good many ways in which we get heat. People who are under the sun or near a fire get warm. But we ne

20、ed not always be near a fire to get warm. Our rooms may be warmed by a fire which is in another part of the building. There heat of the fire is carried by water running through pipes to radiators, which warm our rooms. From the term “radiator” we can at once see that the heat which warms our rooms c

21、omes through radiation. Radiant heat may travel in the same way as light does. If you put something which you cannot see through between you and the sun, you wont feel its heat. If you put something that is transparent, the heat ray may be reduced a little, but some of it will still come through. An

22、ything that is hot radiates heat ray. Now hold a copper wire in your hand and put the other end over a fire. You cant hold it very long without burning your hand. This shows that heat is carried along the copper wire. In scientific terms we say that heat is conducted from one end of the wire to anot

23、her. And the process is named conduction. The things along which heat passes quickly are good heat conductors. Those that let heat pass very slowly are bad conductors of heat. Our next question is then how does heat travel in liquid. Take water for example. Cold water is heavier than warm water and

24、goes under it, pushing the warm water up and taking the space where the warm water was. When the warm water gets cold, it becomes heavier and goes down again. The water goes round and round or “circulates”. This circulation of heat is known as “convection”. 4 Electric CurrentAll metals are good cond

25、uctors because there is a great number of free electrons in them. These free electrons usually do not move in a regular way so that there is no current. However, when an electric field is set up, all the free electrons will be made to move in one direction. And an electric current is formed. Or to s

26、ay, in order that an electric current can be produced in a conductor, an electric field must be built in it. An electric field is usually set up by applying a voltage between the two terminals of the conductor. Thus, the free electrons form an electric current in the conductor. There are two kinds o

27、f currents: direct current (D.C.) and alternating current (A.C.). Direct current is an electric current the charges of which move in one direction only. It is constant in value, unless the circuit conditions, such as the applied voltage or circuit resistance are changed. The charges of an alternatin

28、g current change their direction regularly. First they flow one way, then the other. The difference between A. C. and D. C. depends upon the voltage applied. If the electric field applied is unchanged, the current produced is D.C. If the electric field applied is alternating, the current produced is

29、 A.C. Both A.C. and D.C. have their advantages and disadvantages and they are respectively used in different applications. 1光光正象无线电波、X射线等一样是一种电磁波。电磁波在真空中的速度为每秒30万公里。世界上没有比电磁波传播得更快的东西了。但是电磁波的波长和频率是不同的。光的波长比无线电波短，比X射线长，但是光的频率则正好相反，比无线电波的大，比X射线的小。太阳是最大的光源。我们知道地球的上生命都依靠太阳的热。但是太阳的光象它的热一样是生命所必须的。另一种重要的光源是

30、以充特殊气体的管子发出的电火花产生的。这种光源称为“间接光”。我们由象太阳这样的光源直接看到的光则称为“直接光”。正是从生产和科学实验中，我们才了解到光在空间以每秒三十万公里的速度传播。通过实践，而且只有通过实践，这一数字才以许多不同的方法一次又一次被证明是正确的。当你发出“光”这个音的时候，光就能够运行等于地球圆周八倍的距离，从这点上你就会懂得光是何等之快了。光最重要的特性之一是直接传播。如果说不是这样的话，就不可能用肉眼通过来褔枪的瞄准器来精确地瞄准一个物体。然而这绝不是说灯光只是朝一个方向传播的，事实上，灯光是散射的。而且由于光是直线传播的，所以它本身不能拐弯，这就是为什么会有影子的原因。相反，假如光能自己绕个一个物体，那就根本不会有影子。2热传导你一定在烧热的炉子上或其它热的金属上烫过手，你也一定在太阳晒得很热的路上光着脚走过。如果是这样话，一部分热就通过传导而到达你的手上或脚上。这些普通的经验说明了一个重要的原理：每当一个物体接触到另一个物体时，