In the last article, the author looked briefly at the kinds of materials that we might use for high specific output applications such as supercharged or turbocharged engines. In the article we mentioned a couple of the popular 'superalloys' which are used for poppet valves, namely 'Nimonic' and 'Inconel' alloys. Although not as widely used as the Nimonic materials, Inconel is used in the same sorts of applications, and Wayne Ward recently discussed its use as a valve...
Owing to the fact that the subject material of this article is, in itself, fairly unremarkable, we should, perhaps, consider what it is that makes a material advanced. Is it significant that it is of an unusual composition? Perhaps we consider a material to be advanced if it has unusual or desirable properties. Possibly a combination of criteria make a material seem advanced to us. An interpretation which I would like to use, for the purposes of this article at least, and perhaps for other...
Connected between the flywheel and the continuously variable transmission of the Flybrid, mechanical KERS is an epicyclic gear system, the focus of this article. Epicyclic gearing is a gear system that consists of one or more planet gears, rotating about a central sun gear. Typically, the planet gears are mounted on a movable arm or carrier which itself may rotate relative to the sun gear. Epicyclic gearing systems may also incorporate the use of an outer ring gear or annulus, which meshes...
The terms rolling contact bearing, anti friction bearing and rolling element bearing are used to describe that class of bearing in which the main load is transferred through elements in rolling contact with each other. Friction in a rolling element bearing is present, but it is negligible when compared to the starting friction of a journal type bearing. The load, bearing speed and the viscosity of the lubrication all affect the friction within the bearing. Although it is not technically...
Perhaps the most noticeable trend in lubricant technology over the last 30 years or so is the movement towards lower viscosity oils. The relentless drive for greater efficiency and hence higher power has led to developments where in the past claims of an increase of up to 25kW have been made in a Formula One engine just by changing the oil. Whether you believe this to be true or not is immaterial but research over the years has shown that reducing the viscosity of the oil can lead to...