Duke Engine - looks promising

**Mguy** · December 19th, 2014 11:06 PM

Check out this video introducing a new type of engine. Its small and compact. Could be the engine of the future.

https://www.youtube.com/watch?v=c19kn3drdFU

**niky** · December 20th, 2014 01:45 PM

While watching that, I couldn't help but wonder:

How much oil does it use in normal operation? It's basically a rotary piston engine, and from the way it turns, it'll need lubrication between the cylinder head and the revolving cartridge holding the pistons. I notice they focused on greenhouse gases without mentioning hydrocarbon emissions... which are bound to be worse than a standard piston engine.

How bad will sealing problems be over time? It looks like it will require better sealing than a rotary, and the gasket shape will be much, much more complex, and subject to shearing forces from complex moving parts sliding across it.

Also: high compression, yes, but what are the rpm limits? (very good for an axial... but compared to reciprocating... ?) and how do you optimize operation across rpm ranges without valves? That was another issue with rotaries... without a variable geometry turbo, you can't boost low-rpm torque or optimize operation over a wide range of speeds.

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Might have merit as a generator-type motor, I guess... But I struggle to see how it can be applied otherwise.

**StockEngine** · December 20th, 2014 06:27 PM

Not meant for automotive applications.

**niky** · December 20th, 2014 11:16 PM

Originally Posted by StockEngine

Not meant for automotive applications.

As a standalone power generator, a small piston-powered engine is one of the worst ways to do it. For economical power generation, you're looking at doing large scale diesel installations first, since those produce lots of electricity at low revs.

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Right on the Duke website, they claim automotive applications, aviation, marine and range-extender applications.

They also claim friction levels are comparable to regular piston engines.

Sounds great... and since the engine's operation is more akin to two-stroke than four-stroke, power levels should be higher... but I'll believe it when I see it. The design should naturally lend itself to higher hydrocarbon production and oil usage over time... so it remains to be seen if traditionally conservative aircraft and automobile manufacturers will be willing to take a gamble on something so odd.