THE expression sinall is beautiful hasbeen proved true in the case of the internal combustion engine. Rick Mayne andhis colleagues at Split-Cycle Technologyin Arundel, Queensland, Australia, havesubstituted a few large pistons with scera small ones in a 2-stroke engine andclaim that this would sharply reduceenergy losses and wear and tear that friction between the moving parts andvibrations cause (Vcw Scieritist, Vol 146, No 1977).
The new engine, called the splitcycle engine, would ensure almost complete combustion of the fuel and soemissions would be virtually rwn existent. The scientists also claim that thenew engine could run on low-grade fuels such as coconut oil and fuel mixtures containing up to 60 per cent steamby volume.
Mayne used several small pistonsfiring together instead of the traditionalsingle firing at a time of a few large pistons to drive a 2-stroke engine. Theclaims that this substitution of pistonsenables not only a more efficient combustion of fuel, but also makes for thepistons to be fired at a slower rate(because there are more of them nowthereby reducing w car and tear.
Mayne's engine is circular with thecrankshaft 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 24out," says Mayne.
The pistons move in and out at aspeed of about 50 nictres per minute -20 times slower than pistons in conventional engines. The crankshaft of theengine moves at around 300 revolutionsper minute, which is 10 times slowerthan conventional shafts.
The split-cycle engine is to undergoindependent testing at universities inthe us and Mayne and his colleagues arepreparing to test it for the first time in avehicle, "We are very close to runningone in a motorcvcle, " says Mayne.