Duke Engine

[SmarterAlex]

Just when I thought everything had been invented. Fancy one of these new engines in your car?

http://www.gizmag.com/duke-engines-axial/33631/

[Thrumbleux]

The 'barrel' or 'swash plate' engine was invented a long time ago! And the Duke is a variation on that theme. Bristol IIRC did a Z-crank model which the Duke is very similar to.
What confuses me with the Duke though is that it appears to operate on 2-stroke principles - of which I favour. But the emissions regulators don't!
I've just browsed the page so maybe there's more info but there doesn't appear to be the valving a 4-stroke would require.
If they've licked all the problems associated with 2-strokes then they deserve to succeed.

[tolsen]

Pistons and cylinders will be conventional so there is not much chance this Duke will ever take off unless outfitted with cylinder head valves. Valves do not need to be driven by cams. Indeed there are pub sized marine engines where the valves are externally actuated.

[Thrumbleux]

pub sized marine engines where the valves are externally actuated.

Actuated by what if not cams TK?

[Evilution]

Solenoids.

[SmarterAlex]

Yes. The Barrel engine has been around an extremely long time. It's brand new to me though. Exciting

[Thrumbleux]

I've just browsed the page so maybe there's more info but there doesn't appear to be the valving a 4-stroke would require.

Looked at more closely and it is a 4-stroke. The problem they will face or have a unique solution to is sealing the rotating cylinder to the head face under pressure. Not an easy trick to pull off. Time will tell, but even if they've got it right the major manufacturers are so wedded to NIH syndrome Duke may well struggle to gain acceptance. Just ask Gomecsys...

[Mr T]

Actuated by what if not cams TK?

Have a look at the Fiat Twin Air engine. The inlet valves are operated by variable solenoids, therefore doing away with the need for a throttle body, If I remember correctly.

[Thrumbleux]

Have a look at the Fiat Twin Air engine. The inlet valves are operated by variable solenoids, therefore doing away with the need for a throttle body, If I remember correctly.

Right enough, I'd forgotten about Twin Air. Hydraulic operation with the hydraulics being under solenoid control is how it's configured IIRC. (Direct solenoid operation of valves is still a holy grail for the motor industry - making them powerful enough to accelerate the valve at rates appropriate to high rpm being the issue. Fine on the very slow running marine engines TK alluded to though). Direct solenoid operation would be fantastic but I guess the Twin Air does a pretty decent job for now. Nothing beats a piston ported 2-stroke for valving simplicity though - just a pity it has that one inherent weakness.