Duke Engines are in an advanced stage of developing a unique high-speed, valve-less 5 cylinder, 3 injector axial internal combustion engine with zero first-order vibration, significantly reduced size and weight, very high power density and the ability to run on multiple fuels and bio-fuels.
The Duke engine is suited for many uses including marine, military, automobile, light aircraft and range extender applications.
The Duke engine’s 5 cylinder, 3 litre, 4-stroke internal combustion engine platform with its unique axial arrangement is already in its 3rd generation. During development the Duke has been tested at Mahle Powertrain in the UK & in the USA, and test results are available.
In comparisons made to conventional IC engines with similar displacement, the Duke engine was found to be up to 19% lighter and up to 36% smaller.
The Duke’s unique counter rotation, 3 dimensional, almost vibration free motion and the innovative methodology employed to achieve this, addresses previous limitations that have prevented the commercialisation of axial piston engines to date, especially at higher power and speed.
- The Engine has negligible 1st-order or 2nd-order Vibration.
- Duke offers designers greater freedom. Duke’s axial geometry creates a very compact cylindrical package, allowing for a wide range of design applications, limited space fit, aerodynamic optimization and ease of installation.
- Engine delivers high thermodynamic efficiency. The absence of hot valves in the favorably shaped combustion chamber allows high compression ratios for efficient operation on low octane fuels. With only 3 exhaust headers for 5 cylinders there is a low surface area for heat loss prior to any catalytic converter, offering a potential catalyst light-off benefit.
- Engine offers wide fuel flexibility.
- Engine is far less complex than traditional IC engines.
- Engines is committed to Research & Development, with further advances already underway.
- The Duke Engine has IP protection. Throughout the development process, Duke Engines has filed patent applications to protect its technology.
Duke Engines is now at a third generation of the engine and currently developing the next generation of the technology, including running with kerosene and biofuels and exploring the unique design characteristics of the engine to allow Variable Compression Ratios.
1993……………..The idea of the Duke engine is born.
1995……………..Duke Proof of Concept (POC) build begins.
1996……………..POC runs for the first time. University of Auckland do kinematic analysis of POC
1998……………..V1 (996cc) engine tested up to 3500rpm on University of Auckland dyno.
1999……………..V1 installed in Daihatsu Charade.
2000…………….V2.1 (933cc) build begins
2003…………….V2.1 engine tested on University of Auckland dyno. Tested up to 4500rpm and produced 31kW
2004…………….V2.2 (933cc) runs at 6500rpm. A 30 hour drive cycle is completed at Auckland University.
2005…………….V3 (3-litre) build begins.
2006…………….V3 tested on University of Auckland dyno with impressive results.
2007…………….100Hr drive cycle test on UoA dyno with V3.V3 tested & benchmarked at Mahle Powertrain (UK)
2008…………….Improvements to fuel preparation.
2009…………….New “bottom end” design iterations for V3i.
2010……………..V3 is run on JetA1 at UoA dyno.
2011……………..V3i successfully tested on both petrol and JetA1 at UoA dyno.
Co-development partnership formed with Mahle Powertrain (US)
As well as Automotive applications the Duke Engine lends itself well to Marine, Aircraft and Generator/Utility Range Extender options. The output shaft, being ‘geared down’ to 5/6 of the piston reciprocating speed, allows the ‘engine-out’ torque to be higher and maximum torque to be developed at lower speeds. Engine is generally well suited to many applications of 40 kW or greater.
Duke engine would be best suited to marine applications of approx 50kW or greater, with the low vibration from the engine providing performance benefits in all marine applications.
Duke engine in a vertical shaft application presents all the manifold, fuel and ignition system on its upper face, allowing simple service access.
The service access items on the engine are installed on the front face of the engine in this application, allowing easy access even when engines are close coupled to the flat window surface.
The cylindrical shape of engine lends itself well to installation in small cowlings with lower drag, and the superior balance and vibration characteristics of axial engine will be appreciated in many aerospace applications, leading to lower air-frame vibration, fatigue and mount isolation requirements.
Duke’s counter-rotating cylinder group offers partial cancellation of gyroscopic torque reactions. Output shaft intrinsically “geared down” to 5/6 of the piston reciprocating speed allows the engine out torque to be higher and max power developed at lower speeds.
5) The Ideal Range Extender
The Engine lends itself well to Marine, Aircraft and Generator/Utility, Automotive and Hybrid electric vehicle Range Extender Applications. Engine output shaft, intrinsically ‘geared down’ to 5/6 of the piston reciprocating speed, allows the ‘engine-out’ torque to be higher and maximum torque to be developed at lower speeds.
Data Courtesy from www.dukeengines.com