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Harry Schoell's Cyclone Power
Alternative Fuel Engine

A 21st Century
Compact and Powerful Steam Engine

cyclone power is a radial steam engine

Cyclone Power burns alternative fuels: Biomass such as algae, orange peels, recycled French fry grease and fossil fuels including propane and waste oil. It also runs without carbon-based fuel on waste heat.

Simply put Harry Schoell's Cyclone Power engine is a highly modified Rankine Cycle regenerative, external combustion engine that creates mechanical energy by heating and then cooling de-ionized water in a closed-loop. The inherently lower operating temperature and longer duration fuel combustion pays big dividends in greatly reduced emissions.

In other words what we have here is a flash boiler. Atomized fuel injected into the centrifugal combustion chamber. Ignition spark fires the fuel/air mixture and the flame spins around a heat coil. Duration of combustion is controlled in order to maintain a constant temperature. In as few as five seconds after start-up, water circulating in those coils transforms into super heated steam up to 1200 degrees Fahrenheit. The super-heated steam flows to the six-cylinder radial configuration. Flow regulated to control torque and rpm Conventional, vintage steam engines for cars operated at 400 to 1200 psi while Cyclone Power runs at a lofty 3200 psi.

No motor oil is used, instead the de-ionized water is both the steam and lubricant. Because of the valves design, the engine cranks independently there is no a starter motor. This radial engine is essentially a steam engine so naturally it follows it generates maximum torque with the first turn of the crank. So just like a steam engine there is no transmission. After doing work, ie, moving the pistons in their cylinder bore) steam exhaust flows to a condenser unit where it precipitates back into water. Blowers circulate fresh air around the condenser in order to speed the condensation.

Here's where it gets really good. Air, heated from the condensing unit, flows to a second heat exchanger in order to pre-heat air flowing into the combustion chamber. It's the exact opposite of a gas or diesel engine that needs cool air. The regenerative also cooling the exhaust fumes down to about 3200 degrees Fahrenheit. Think of it this way: The Cyclone Engine captures otherwise wasted heat from the cylinders to pre-heat the working fluid (water) before returning to the combustion chamber.

Finally, a high-pressure pump flows water from the collecting pan to the heat coils via heat exchangers surrounding each of the cylinders and then onward to the center of the coils to start the heat cycle again. In short, the Cyclone is a 21st century, high efficiency, compact and powerful steam engine.

The Cyclone Engine is a highly efficient with thermal efficiencies nearing the top diesel engines on the market today, including common rail diesel. Higher efficiency means less fuel required to produce the same work.Pressures in the range of 3200 psi with temperatures of about 1200 degrees F cause super-critical vapor to act as a fluid.

High Compression, High pressures allow the cubic capacity of the engine to be small in relation to the horsepower developed. Gas internal combustion engines generally develop one horsepower per 1.5 cubic inches of displacement, whereas the Cyclone can develop 2.5 horsepower per cubic inch. Schoell's Cyclone Engine has only a few components and they are fabricated from inexpensive, non-exotic materials meaning manfufacturing and mainting costs are modest.A 350/lb Cyclone Engine of 38-cu/inch displacement develops over 850ft/lbs of starting torque (which is more than necessary to eliminate the transmission). Transpose the decimal to 380 cu/inches and you will appreciate the implications of this technology when a manufacturer scales the Cyclone to a size suitable for heavy road transport. The starting torque of the Cyclone Engine is higher than an electric motor of comparable size, but similar in respect that neither requires a transmission, just a simple forward neutral and reverse lever is required.

Harry Schoell's Cyclone Rankine cycle engine

How the Cyclone Engine Works

Atomized fuel is injected into the centrifugal combustion chamber (shown as elevated over the bank of radial cylinders), where a spark ignites the fuel-air mixture. The cyclonic flame spins around the heat coils. Thermocouples control the duration of combustion event in order to maintain constant temperature.

In as few as five seconds from start up water in the coils super-heats intosteam as hot as 1200 degrees F. It enters the cylinders via special valving, timing mechanisms that regulate the volume of steam enters the cylinders. The longer the duration, the greater the torque and acceleration. Steam, under pressures as high as 3200 psi, power strokes the pistons.

Portrait of harry Scchoell

Besides the Cyclone Power engine, designer Harry Schoell is best known for the Duo Conic hull that revolutionized boat performance. Mister Schoell also owns an impressive number of other marine-related patents including designs for a trimmable surface drive, a surface-piercing propeller, a water jet, a combination fuel injector/spark plug and surface effect vehicle.

WHE-25 Specifications
Cylinder Block Configuration 6-Cylinder
Cycle Rankine
Bore x Stroke
1.87 x 1.5
Operating Pressure
25 to 200
Operating Range 5000-6000 rpm
Maximum Pressure
Operating Temperature

500 to 700
Maximum Output
3000 rpm
200 psi
600 Fahrenhit
Alternator and
18 Pounds

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