The illustration above highlights the benefits of the Vengeance Vane & Rotor expander design over the traditional piston & crank design. For simplicity, a piston expander with a 1:1 bore-to-stroke ratio (bore diameter = vertical stroke length) is used as a benchmark. Modern piston engines/expanders may vary slightly from this ratio but can never come close to the incredible torque of the Vengeance design with the same pressure input. If you study the difference between the forces acting on the Piston and on the Vanes under equal pressure, you will notice there is much more force acting on the piston and crank while providing much less torque.  This is a major flaw in the piston & crank expander design and a tremendous waste of energy.   

The Vengeance engine size depicted above is less than 1/2 the size of an equal displacement V-8 Piston 4-stroke internal combustion engine and smaller than an equal displacement 4-cylinder 2-stroke engine or expander. Other Vengeance designs can deliver more torque by a factor of at least 2. 



    Twice the power, half the weight and cost of equal displacement piston engines.  


    No high friction points such as piston to cylinder wall contact means less energy wasted during combustion
    No sliding bearings - roller bearings throughout engine reduce stress, friction and wear
    Reduced friction, tremendous torque and no valve restrictions means engine can idle below 50 RPM
    Reliable as no need for bearings to ride on a film of oil like crank and rod bearings of piston engines
    No catastrophic failure due to oil pressure loss as roller bearings will keep rolling until engine is stopped
    Fewer oil changes as the oil is not subjected to the same harsh conditions as in piston engines
    Uses a fraction of the oil of a comparable piston engine 

  • Low part count, no pistons, no crankshaft, no connecting rods and no valve-train
    Fewer moving parts means less chance of part failure
    Debris getting past a damaged air filter will easily be swept out without causing damage
    Easier and cheaper to manufacture, maintain and rebuild
    Maximum torque at any RPM means fewer gears, smaller, simpler, cheaper transmission
    Engine can be mounted in any position with minor modifications
    All components are easily accessed for servicing and wear items such as roller bearings are replaceable
    Tune ups are simple as the spark plugs are located right on top of the engine block without any restrictions

  • Combustion gases expand fully inside the engine block and not inside the exhaust port reducing noise
    Eight power impulses per one revolution translates into a smoother running engine minimizing vibration
    Explosive combustion forces are put to work immediately eliminating severe hammering of components

    True rotary motion eliminates “stopping” during combustion unlike reciprocating piston engines which allow time for valuable heat energy to escape through the chamber walls reducing efficiency, promoting incomplete combustion and raising emissionsHeat from combustion is contained inside the combustion chamber for a longer period of time to break down more of the fuel to be converted into mechanical work to turn the output shaft
    Multiple spark ignition, greater dwell time and HCCI capability results in a more complete combustion
    The rate of chamber volume increase is controlled during combustion reducing heat and pressure loss
    Intake chamber is separate from combustion chamber allowing for a hotter combustion chamber
    No valves means no restrictions in air flow so the intake chamber is always filled to its optimum volume
    No valve timing to open and close at certain RPM therefore maximum torque is provided at any RPM
    Gasoline and Natural Gas Fuel Efficiency: Over 50%,     Diesel Fuel Efficiency: Over 60% 

  • Conventional IC Fuels:  Gasoline, Diesel, Propane and natural gas
    Conventional EC Fuels: Fuel Oils, Kerosene, JP-8
    Alternative/Renewable Fuels:  Bio-diesels, Alcohols, Syn-gas from organic waste through gasification
    Zero Carbon Fuels:  Hydrogen, Ammonia
    Easily converted to run on different fuels 
    Direct injection capable (HCCI) for increased performance and efficiency
    Separate intake and combustion chambers avoid pre-ignition and back-firing from highly volatile fuels like hydrogen
    Can run as internal and/or external combustion engine, compressed air expander or pressurized steam expander
    Can easily alternate on the go from internal combustion to external pressure from an outside source




Conventional Rankine cycle/steam turbines are designed to run at maximum efficiency at speeds so high that any condensate droplets forming downstream in the exhaust section can lead to erosion and catastrophic damage to the blades.  For this reason, more heat is added to ensure the vapor remains above 90% dryness.  Some turbines add more than one re-heat stage to "zig-zag" to the right of the Dry Saturated Vapor Line.  The extra heat and equipment added for superheating comes with a heavy price tag.  Furthermore, in a closed-loop system, any residual superheat will have to be dealt with in the condenser.  This also increases the size, cost and loading of the condensing unit.   

The Vengeance Expander design allows more expansion, going deeper into the wet vapor region as it can tolerate high condensate formation.  In fact, the Vengeance design can operate as an excellent hydraulic motor or pump.  Allowing more expansion decreases exhaust pressure and temperature, putting less strain on the condensers and increases net system efficiency.  It also allows for more efficient use of low heat and low pressure "wet steam" boilers and pressurized refrigerant-driven Organic Rankine Cycle (ORC) heat exchanger/evaporator systems. 






  • Comparatively high electric efficiency for small-scale CHP units (up to 1Megawatt range)
    Excellent partial-load efficiency over a wide range of load conditions
    Runs efficiently in both back-pressure and condensing turbine modes
    Load fluctuations between 10% and 100% of nominal electric power production are no problem
    Not sensitive to steam quality or flow fluctuations
    No high velocity steam nozzles to clog or clean periodically
    Rapid stop and start times
    Water droplets in steam from boiler malfunctions or fuel quality changes pose no threat
    Steam and oil cycles are completely separated by an air-lock system
    Fully automatic operation and easy handling saves staff costs
    Compact size, rugged construction, easy setup, low maintenance costs
    No isolated anti-vibration concrete pad needed


  • Automotive:  Cars, Trucks, Vans, Motorcycles, SUVs
    Marine:  Powerboats, Pleasure Boats, Super Yachts, Cruise Ships, Ocean Freighters
    Aerospace:  Propeller Driven Aircraft, Helicopters, Heavy Lifting 
    Military:  All Terrain Vehicles, Trucks, Tanks, Utility Vehicles, Amphibious Vehicles, UAVs, Combat Boats
    Public:   Freight and Passenger Trains, Busses, 
    Recreational:  Snowmobiles, Jet Skis, All Terrain Vehicles, Motor Homes, Go Carts
    Domestic:  Lawn & Garden Equipment, Pumps, Generators, Compressors
    Industrial: Construction, Agriculture, Forestry, Mining, Drilling, Portable & Stationary Power Generation
    Environmental: Waste Heat Recovery, Green Power Generation


© 2009 Vengeance Power Inc.