Friday, April 06, 2007

We need more efficient cars

Enter the Six-stroke Engine which its inventor, Bruce Crower, claims can get up to 40% better fuel efficiency.
Wiki can explain it better than I can.
The engine cold starts on the conventional four stroke Otto cycle, coasting through the fifth and sixth strokes for a short period. After the combustion chamber temperature reaches approximately 400 degrees Fahrenheit ( 200 C ), a mechanical operation phases in the fifth and sixth cycles. Just prior to the fifth-cycle, water is injected directly into the heated combustion chamber via the converted diesel engines fuel injector pump, creating steam and another power stroke. The phase change from liquid to steam removes the excess heat of the combustion stroke forcing the piston down (a second power stroke). As a substantial portion of engine heat now leaves the cylinder in the form of steam, no cooling system radiator is required. Energy that is dissipated in conventional arrangements by the radiation cooling system has been converted into additional power strokes.
Read more on the pros and cons on wiki.
Also an article about the invention in Autoweek

Now if they also add a continuously variable transmission they might get an extra 20% efficiency.

More work needs to be done on these kinds of technologies.


pimp-a-lot bear said...

nice post!

But I doubt they'll ever implement this technique. If you take a look at the Stirling cycle, which also gives a high efficiency, but never made it to the automobile-industry due to high weight & capital costs.
Nowadays it's becoming financially interesting because of the higher fuel prices.

On the other hand, the Crower cycle provides great weight reduction, since it doesn't need a heavy cooling mechanism.

annom said...

Brilliant invention! Somewhat straightforward, if you hear it.

If it turns out to be really efficient and more money and manpower is put into developing this conecpt, it might make it to the automobile-industry.

I hope Sterling engines will be used more often in the future. The Stirling idea is super brilliant. They are used in in these prototype solar power plants.