Making pistons smaller and more numerous increases an internal combustion engine's efficiency
THE expression sinall is beautiful has
been proved true in the case of the internal combustion engine. Rick Mayne and
his colleagues at Split-Cycle Technology
in Arundel, Queensland, Australia, have
substituted a few large pistons with scera small ones in a 2-stroke engine and
claim that this would sharply reduce
energy losses and wear and tear that friction between the moving parts and
vibrations cause (Vcw Scieritist, Vol 146, No 1977).
The new engine, called the splitcycle engine, would ensure almost complete combustion of the fuel and so
emissions would be virtually rwn existent. The scientists also claim that the
new engine could run on low-grade fuels such as coconut oil and fuel mixtures containing up to 60 per cent steam
by volume.
Mayne used several small pistons
firing together instead of the traditional
single firing at a time of a few large pistons to drive a 2-stroke engine. The
claims that this substitution of pistons
enables not only a more efficient combustion of fuel, but also makes for the
pistons to be fired at a slower rate
(because there are more of them now
thereby reducing w car and tear.
Mayne's engine is circular with the
crankshaft in the centre. Forty-eight pistons are spread out along the rim of the circle and 24 of them fire simultaneously. "What we have is a constant breathing motion, with 24 (pistons) in and 24
out," says Mayne.
The pistons move in and out at a
speed of about 50 nictres per minute -
20 times slower than pistons in conventional engines. The crankshaft of the
engine moves at around 300 revolutions
per minute, which is 10 times slower
than conventional shafts.
The split-cycle engine is to undergo
independent testing at universities in
the us and Mayne and his colleagues are
preparing to test it for the first time in a
vehicle, "We are very close to running
one in a motorcvcle, " says Mayne.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.