内燃机专业英语翻译

A thermal cracking process was developed whereby heavier oils were heated under pressure and decomposed into less complex more volatile compounds. These thermally cracked gasolines satisfied demands, but their higher boiling point range created cold weather starting problems. 16. Houdry 发现蒸发的油在450至480度的温度下经过活性催化剂可转化为高质量汽油，比热裂解的产出高得多。这些进步以及其它改进使具有更好抗敲缸性能的燃料可以大量生产。

Houdry found that vaporized oils passed over an activated catalyst at 450 to 480 C were convented to high-quality gasoline in much higher yields than was possible with thermal cracking.These advances, and others, permitted fuels with better and better antiknock properties to be produced in large quantities.

17. 在过去的三十年中，要改变的新因素变得非常重要并严重影响机器的设计和运行。这些因素是，其一、需要控制车辆对城市空气的污染，其二、需要对车辆燃油消耗进行大幅度改善。

During the past three decades, new factors for change have become important and now significantly affect engine design and operation.These factors are, first, the need to control the automotive contribution to urban air pollution and, second, the need to achieve significant improvements in automotive fuel consumption.

18. 大幅度降低SI排气系统的废气并考虑到含铅抗敲缸添加剂的毒害使得无铅汽油作为主要车辆燃料重新返回市场。含铅汽油中的最大

含铅量大幅降低。排放控制的要求以及燃料的改进使内燃机设计和运行上发生了很大改变。

Both the use of catalysts in spark-ignition engine exhaust systems for emissions control and concern over the toxicity of lead antiknock additives have resulted in the reappearance of unleaded gasoline as a major part of the automotive fuels market. Also,the maximum lead content in leaded gasoline has been substantially reduced.The emission-control requirements and these fuel developments have produced significant changes in the way internal combustion engines are designed and operated.

19. 原油价格猛涨到1970年的几倍，（人们）开始担心石油的长期可持续性。大幅度提高内燃机效率的压力明显增加。然而，排放控制的要求使改善燃料消耗举步艰难。

During the 1970s the price of crude petroleum rose rapidly to several times its cost in 1970, and concern built up regarding the longer-term availability of petroleum. Pressures for substantial improvements in internal combustion engine efficiency have become very substantial indeed. Yet emission-control requirements have made improving engine fuel consumption more difficult.

20. 人们可能认为经过了一个多世纪，内燃机（技术）已经达到顶峰，没有进一步改善的潜力。实际并非如此。传统内燃机在效率、功率、排放水平方面都在不断改善。

It might be thought that after over a century of development, the internal combustion engine has reached its peak and little potential for further improvement remains. Such is not the case. Conventional spark-ignition and diesel engines continue to show substantial improvements in efficiency, power, and degree of emission control.

21. 新材料的出现为降低重量、成本和热损失提供了可能。其它类型的内燃机，比如可使用多种燃料的分层充量内燃机，有可能会更有吸引力并得到大量生产。

New materials now becoming available offer the possibilities of reduced engine weight, cost , and heat losses, and of different and more efficient internal combustion engine systems. Alternative types of internal combustion engines, such as the stratified-charge with its wider fuel tolerance, may become sufficiently attractive to reach large-scale production.

22. 未来内燃机的改进潜力无穷，但这将对汽车工程师提出艰巨的挑战。随着我们对内燃机知识的不断拓宽，这一切都会变为可能。 The engine development opportunities of the future are substantial. While they present a formidable challenge to automotive engineers, they will be made possible in large part by the enormous expansion of our knowledge engine processes. 1.2 Engine classifications

所有这些特征都很重要，它们显示了现有内燃机设计的范围。由于我们想从根本上了解内燃机的运行和排放特征，点火方式被选为最主要的分类特点。不同点火方式（火花点火或压缩点火）伴随使用燃料、混合物准备方法、燃烧室设计、负载控制、燃烧过程的详细过程、排放、运行特点等重要特征。

All these distinctions are important and they illustrate the breadth of engine designs available. Because this book approaches the operating and emissions characteristics of internal combustion engines from a fundamental point of view, the method of ignition has been selected as the

primary

classifying

feature.

From

the

method

of

ignition-spark-ignition or compression-ignition --follow the important characteristics of the fuel used, method of mixture preparation, combustion chamber design,method of load control, details of the combustion process, engine emissions, and operating characteristics. 1.3 Engine operation cycles

1. 书中主要讲了往复式内燃机，在那儿活塞在缸内前后运动，通过连杆和曲柄装置将动力传送给驱动轴。曲柄稳定的转动致使活塞循环运动。活塞在上止点和下至点停止运动，这时分别对应容积最小和最大。

Most of this book is about reciprocating engines, where the piston moves back and forth in a cylinder and transmits power through a connecting rod and crank mechanism to the drive shaft. The steady