Duke Engines - for the mechanically inclined

What's the advantage to this over conventional piston engine design? And how can there be no valves? No intake nor exhaust?
It looks complicated.

Watch the youtube vid. It is short and answers both questions. It would have about half the moving parts compared to a conventional motor and unlike a rotary, good compression.

The gif is a similar design. The one in the video has a power output section that differs significantly.

I suppose the seal is a reinforced carbon assembly that runs in lubricant with the other parts. They don't say specifically.

The sudden stopping is interesting because I don't think the nutating plate would transfer force back into the motor very well. It is like a worm & wheel in that regard. I can only guess that there is some energy dissipating or slip device in the output gearing.

I gather they are going after the marine and aviation market with this thing.

I don't know exactly how it seals, but this is (roughly) just an axial swash plate pump converted into an engine. It should work.

Spinning the whole engine block is really going to do bad things to throttle response though.

I wish the Dynacam engine had caught on. Much more efficient design.

That shouldn't happen. We've been using swash plate pumps for decades. Why would this be much worse?

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 That's a lot of rotating mass. 

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I would think that it would tend to torque the vehicle to one side under heavy acceleration.

So their main selling points are that the design reduces the number of total parts and allows for increased compression ratio.

As for reducing the number of parts, this is nearly irrelevant. Who cares how many parts are in the engine as long as they last. This will impress me when you can stick it in a 4runner and it won't need a rebuild until 300k miles.

As for the compression ratio, 14:1 is higher than what current gasoline engines run, but not the point of being revolutionary. In the 1960's many cars with high performance engines had compression ratios of 12:1. Fuel standards drove CR's down for a few decades, but now with direct injection engines are getting back to that point (porsche's 911 GT3 RS has a CR of 12.9:1)

Also I am not clear as to why thy claim to be able to run a higher compression without pre-ignition. What specifically about this design allows for a higher CR with no detonation? Perhaps in a 70 degree lab and no humidity, but can it be replicated in real world conditions?

Apparently they claim to do it with lower cylinder temps. Can it vary displacement?

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lower cylinder temperatures are going to help, but there's no getting around the adiabatic heat of compression at higher CR.

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Yep. I suppose this is why the increase in CR is minor. If they could achieve 18-20:1 they'd have something to brag on, but 14:1 is barely better than what is being done with standard gasoline engines. Yawn stretch.