Motor Authority: Ilmor Engineering Shows Off 5-Stroke Engine Concept

[NewsFeeder]

With the automotive world striving for smaller, more efficient engines in a bid to be seen as environmentally-conscious and attract customers, scientists and engineers are coming out of the woodwork with new combustion engines, electric powertrains and other systems that they tout as the future of automotive technology - just this month we already saw EcoMotors' opposed-piston opposed-cylinders project that promised to revolutionize engine design. Now, an engineering firm by the name of Ilmor has announced its own new redesign of the internal-combustion engine, with claims that efficiency gains of between 5% and 20% can be had.

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[loki]

interesting.

[dwightlooi]

Ah! somebody is trying to apply the multiple expansion cycle to the internal combustion engine. The concept was widely applied in steam engines. The idea is to have the expanding gases do work in multiple cylinders in multiple stages to extract a greater amount of energy from it. It is a sound concept. The only concerns being that the 3-cylinder design essentially only has two firing cylinders so civility may be an issue. Also, with only one small exhaust valve per side cylinder feeding a central cylinder, breathing may be limited especially at higher revs.

Triple Expansion Steam Engine

[Robert Hall]

peaking of alternative engine technologies, did the Miller cycle engines die with the Mazda Millenia? I don't think I've heard of their application since that car..

Another technology I remember reading about a lot 25 years ago or so were stratified-charge engines..not sure where that went.

Rob

Edited August 10, 2009 by Cubical-aka-Moltar

[dwightlooi]

peaking of alternative engine technologies, did the Miller cycle engines die with the Mazda Millenia? I don't think I've heard of their application since that car..

Another technology I remember reading about a lot 25 years ago or so were stratified-charge engines..not sure where that went.

Rob

The Miller Cycle did, although the concept of creating a pseudo asymmetric intake and exhaust stroke by closing the intake valves very late is very much alive. The engine in the most hybrids today are Atkinson cycle powerplants which do exactly that (minus the supercharger). The in fact, current Civic's R18A engine is part time Atkinson, using the i-VTEC system to switch to an set of atkinson cycle intake cam lobes at low load and moderate engine speeds.