The Duke engine is a four-stroke axial reciprocating engine where the cylinders are aligned with the central crankshaft. It is lightweight, compact, valveless, and vibration-free with high power density. The Duke engine can run on various fuels including gasoline, ethanol, diesel, and kerosene. It is well-suited for aerospace, marine, and light aircraft applications due to its small size, low weight and vibration, and ability to run on multiple fuels.

1. DUKE 4 STROKE AXIAL ENGINE

2. LAYOUT
 Introduction
 Flexibility in fuel
 Advantages
 Applications

3. WHAT TYPE OF ENGINE IS THE DUKE ENGINE
 The Duke engine is a four stroke "axial"
reciprocating engine. "Axial" because the
axis of each cylinder is aligned with the
axis of the output/crank shaft. Axial
engines are sometimes called 'barrel' and
'Z-crank' engines. The Barrel shape is a
result of the pistons being spaced evenly
around the central Crankshaft and aligned
parallel to the Crankshaft axis.

4.  The cylinder group rotates counter to the
crankshaft, at about 20 percent of crankshaft
rotational speed. The counter-rotating design
allows the engine to partially supresses
torque reaction and cancel vibration.
 The five cylinder engine requires only three
fuel injectors and three spark plugs. The
absence of exhaust valves reduces the
potential for pre-ignition or spark knock when
operating on low-octane pump gas.

6. OFFERS COMPLETE FLUE FLEXIBILITY
 Development will allow operation on all
appropriate fuels, including
ethanol/methanol and blends, bio-
ethanol, LPG, CNG, hydrogen, kerosene
and diesel. Spark ignition Duke engines
are currently successfully running on 91
octane gasoline and kerosene/jet-A1.

7. ADVANTAGES OF ENGINE
 The Duke engine is the world’s only viable
axial, 4 stroke, spark ignited piston engine.
 It is lightweight, small, valveless , vibration-
free, has very high power density, and runs
on most fuels, including kerosene/jet fuel.
 The Duke engine is a great fit for aerospace
applications, including ultralight,
experimental and UAV platforms.

8. APPLICATIONS
 MARINE
 The axial arrangement of the duke engine
lends itself well to marine
outboard(vertical shaft) and
inboard(horizontal) applications.
 In general, the Duke engine would be best
suited to marine applications with approx
50kW or greater, with the low vibration
providing good performance.

9.  LIGHT AIRCRAFT APPLICATIONS
 Aerodynamically friendly cylindrical shape,
with output shaft on centre line
 Simplicity of design
 Low weight
 Small size
 Near perfect balance for low vibration