External Combustion Engines

[NeilBlanchard]

The Cyclone external combustion engine looks pretty interesting; and it would seem to have a high efficiency, given the relatively cool exhaust and very low emissions exhaust and continuous burning.


(click on image for link)

Video: A Steam Engine for Your Car

Could Waste Oil Power Your Range-Extended Electric Car One Day? - Green Car Reports

They are claiming over 30% efficiency -- not bad, but not as good as I hoped. This seems to solve many of the issues we've discussed in the internal combustion engines threads; like burn time, and mechanical torque, while it has simple mechanicals and no transmission required. (Sounds a lot like EV's?)

What do you think?

[jamesqf]

I think it'd be a lot better just to go to a Stirling cycle engine, which has max theoretical efficiency. If it's in a Volt-type hybrid, then the slow acceleration &c aren't problems.

[t vago]

What sort of fuel does it run on? Snake oil?

[cfg83]

Neil -

It seems to be liked by a few folks :

Could Waste Oil Power Your Range-Extended Electric Car One Day? - Green Car Reports

The Cyclone Engine was deemed the Invention of the Year for 2008 by Popular Science magazine. It also won awards from the Society of Automotive Engineers in 2006 and 2008.

2008 invention awards | Popular Science
Steam Under the Hood | Popular Science

The Cyclone
Cost to Develop: $2 million
Time: 8 years
As long as the internal combustion engine has been around, garage tinkerers have been trying—in vain—to best it. But Florida boat engineer Harry Schoell, a lifelong inventor with a portfolio of patents, thinks he’s got the answer, in the form of a reinvented steam engine.
...
But steam engines small enough to fit in a car don’t typically produce enough energy to drive it. Schoell’s design, called the Cyclone Green Revolution Engine, gets more power from the steam by making it so hot that it turns “supercritical,” a stage at which it behaves more like a liquid and expands far more than gaseous steam.
Although it can scale up or down, Schoell’s prototype is roughly the shape and size of a backyard grill’s propane canister. Inside a doughnut-shaped combustion chamber at the top, fuel—be it biodiesel, ethanol or gasoline—combusts with air continuously to create a 2,000°F tornado (hence “Cyclone”). Steam circulates around a heat exchanger until it reaches 1,200°F and then pipes into the engine’s cylinders to drive the pistons. As the steam cools, it’s recycled back into the system and reheated.

Maybe it could be used with the plastic-into-oil gizmo :

http://ecomodder.com/forum/showthrea...oil-15542.html

CarloSW2

[NeilBlanchard]

Originally Posted by t vago

What sort of fuel does it run on? Snake oil?

If snakes had oil, it would do fine; sleazy car salesman's hair grease would probably be fine, as well. It can burn virtually any liquid fuel, according to the designer.

The water is a closed loop if I understand it correctly.

[cujet]

Enormous sized, combined cycle steam can near 50% efficiency, as in modern electric powerplants. However, on a small scale, I'd be surprised to see better than 10%. People have tried for years. The results are always the same, and for very good thermodynamic reasons. The temperature that superheated steam requires demands massive energy input. To extract that energy down to a condensate (efficient recovery of all energy input) has always demanded large, non portable equipment. (for all that expansion).

[JasonG]

I've made my share of big steam.
It takes a lot of energy to make superheated steam. It ships well however, very little loss a mile away.
The other issue is steam eats metal, heavy cast iron and steel will be needed to make this engine last.
Good looking drawing though.

[cujet]

Interestingly enough, this company is right down the road from me. I may call them sometime soon and see if I can go by for a look. I'll hold off further judgment until then.

[robchalmers]

THE SIZE OF DARN THING!!!! and that only produces 300+ BHP but it does run on water though so there's the good thing as that that lubricant too.

[NeilBlanchard]

They have working units:



They have tested it independently at 30% efficiency.

I wonder about heat up time. If it was used as a serial steam electric, I wonder if some efficiencies could be gained?