Interesting new type engine

[Timbeck2]

Duke engine in the prototype stage now but looks like it would be great for aircraft.

 

[mondtster]

Looks like a revival of the dynacam engine, which was experimented with a bit in aviation. There's one in the Pima air museum anyway.

https://en.m.wikipedia.org/wiki/Axial_engine

 

[eman1200]

I'm not sure I understand how the combustion cycle works if the piston is moving sideways. seems like you'd have extra (wasted) space there but what the heck do I know.........


EDIT: maybe I should say the 'compression' cycle...like I said, I dunno,

 

[SoonerAviator]

It's been around for a little while. Looks like a complicated Wankel rotary, and I bet they will have same issues with seal wear like the Wankel as well. It sure won't likely be as fuel efficient as a regular V-6 configuration especially with the sliding friction of the rotating piston assembly, despite having such low vibration and frontal cross-section. I'd be surprised if it ever makes it out of the "proof of concept" phase.

 

[flyingron]

The Dynacam had dual ended pistons (imagine you just connected the two rods together on your opposed engines).

The duke is like an old Rotary aircraft engine with the cylinder's bent back 90 degrees. What is kind of neat is they use the position of the cylinder to bring the cylinder past the intake and exhaust ports and the plug. Sort of the way a Wankel works (only with a traditional chamber/piston). I'm dubious about the gains after you deal with having to continually accelerate the bulk of the engine versus the alleged efficiency increase.

 

[RJM62]

It's not that new an idea. I'm unclear about why they expect better fuel efficiency. The rest of it seems to make sense to me.

Rich

 

[Tom-D]

Actually that design is used in the vickers hydraulic pumps and many slow RPM hydraulic motors.The theory is good, but I don't know about the application

 

[Capt. Geoffrey Thorpe]

I'm unclear about why they expect better fuel efficiency.

New engine designs always are expected to have better fuel efficiency / lower emissions / etc. That's how they get people to throw away invest money.

 

[Ted]

I doubt it would end up being lighter in an aircraft when you add in the required liquid cooling system that would go with it. Plus if you have a decrease in efficiency (which I would expect), there goes your weight benefit.

The heavy fuel is interesting. Fundamentally, there's no reason why that engine should run kerosene/Jet-A/diesel any differently than a conventional piston engine. In other words, spark ignition it won't work well, and compression ignition you'll get back to the same weight issues with diesels. So I don't see that being a game changer. It's interesting that the one application I could find for a swashplate engine was in a torpedo. One time use, doesn't need to last very long, highly disposable.

All of these odd engine designs have existed in various forms sometime in the past century. None of them have been compelling enough to cause a major change in the commonly seen internal combustion engine design. That should tell you something.

Still, it's cool to see people trying. I would rather see the FAA let me write "EXPERIMENTAL" on the side of the 414 and let me play around with the TSIO-520s. I could net significant improvements...

 

[Mtns2Skies]

Seems to me that engine would have incredibly little torque. It looks like that plate they use only transfers the energy at a 30-45 degree angle whereas a standard engine applies torque from a range of 5-90 degrees as the crank rotates. But at 90 degrees that's ALL torque.

 

[BigBadLou]

They claim "30% weight saving" and "astounding reduction in number of parts" when they compare it to a 6-cylinder. So there might be a minimum number of cylinders to consider to see any benefit (such as that four-cylinder engines might not be a good candidate for replacement). The reduction of parts, I assume, comes from the simplified valve-train.

However, I would be very wary of the "reciprocator" driving the crankshaft in the opposite direction, that looks like a very high-stress point. I will definitely be looking up more data, including longevity. I wonder what happens to the parts and wear plate after 2000 hours.