新型内燃机效率提高50%
时间：2019-01-14 作者：英语课 分类：VOA标准英语2016年(三月)
This Internal Combustion 1 Engine is 50% More Efficient 新型内燃机效率提高50%
Internal combustion engines in cars may be on their way out, but experts agree it will take a few decades before electric-powered vehicles become dominant 2. Meanwhile, the existing gas and diesel 3 engines can be made more efficient and less polluting. With a $9 million grant from the U.S. Department of Energy, a U.S.-based company is using an old technological 4 concept to build a power train that is 50 percent more fuel-efficient and just as powerful as conventional engines.
This little engine looks like it has only three pistons 5, but in fact, it has six, sharing only three cylinders 7.
With the help of modern technology California-based Achates Power has given new life to the concept of the opposed-piston engine, mostly abandoned after the second World War.
“With the opposed-piston engine, you're able to achieve the efficiency of a much larger engine in a much smaller package," said Fabien Redon of Achates Power.
An opposed-piston engine is a two-stroke engine with separate oil flow. It has no cylinder 6 heads and no valves, both sources of considerable loss of heat and power in conventional combustion engines.
Two pistons move against each other in the cylinder, compressing a fuel-air mixture, which self-ignites, pushing the pistons apart, generating power.
Exhaust gases escape through ports in the cylinder walls.
Stripped of many conventional engine parts, the opposed-piston engine is inexpensive and simple to manufacture.
“We make sure that we do not over scavenge and achieve a very good combustion efficiency, so that hydro nitro-carbons and the emissions 8 are reduced to a great extent," said Redon.
Larger opposed-piston engines have long been used for military and other applications. But developing them for consumer vehicles was not easy.
“This combustion strategy has some difficulties and weaknesses at low loads, because it needs a certain level of temperature inside the combustion chamber 9 to make sure that the gasoline gets ignited," said Redon.
Achates Power, together with Argonne National Laboratory and Delphi Automotive, say they are sure they will overcome the obstacles, and by 2018 will have a 50 percent more efficient three-liter three-cylinder engine that will be suitable for passenger cars and trucks.
- We might be tempted to think of combustion.我们也许会联想到氧化。
- The smoke formed by their combustion is negligible.由它燃烧所生成的烟是可忽略的。
- The British were formerly dominant in India.英国人从前统治印度。
- She was a dominant figure in the French film industry.她在法国电影界是个举足轻重的人物。
- We experimented with diesel engines to drive the pumps.我们试着用柴油机来带动水泵。
- My tractor operates on diesel oil.我的那台拖拉机用柴油开动。
- A successful company must keep up with the pace of technological change.一家成功的公司必须得跟上技术变革的步伐。
- Today,the pace of life is increasing with technological advancements.当今， 随着科技进步，生活节奏不断增快。
- Some pistons have seating rings of metal or leather. 有些活塞上有金属或皮革的密封环。
- A pump uses valves and pistons. 泵使用阀和活塞。
- What's the volume of this cylinder?这个圆筒的体积有多少？
- The cylinder is getting too much gas and not enough air.汽缸里汽油太多而空气不足。
- They are working on all cylinders to get the job finished. 他们正在竭尽全力争取把这工作干完。 来自《简明英汉词典》
- That jeep has four cylinders. 那辆吉普车有4个汽缸。 来自《简明英汉词典》
- Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
- Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。