An ALL new internal combustion engine?

[LAB3]

Let's see if this turns out to be something we see in real life. 160hp, 170ftlbs from a 35lb engine! Talk about having fun, imagine this in a Honda Cub frame!

https://carbuzz.com/news/revolutionary-25000-rpm-engine-is-the-next-step-of-internal-combustion

[wymple]

This is not that new, it's a newer variation on an older idea. It's never been so far as a halfway decent running prototype. I won't hold my breath just yet.

[GS1150Pilot]

Right. Seems to go back to the early 2000's, and hasn't delivered yet. This is from early 2020:

Now comes the hard part: building and operating a proof-of-concept engine. I'm concerned about the lack of seals and lubrication of the rotors operating at relatively close tolerances, and I worry that parts exposed to varying amounts of heat will expand at different rates, causing interference. Exotic materials and tight tolerances can be budgeted into a pricey aviation engine, but can this be made to work on an automotive range extender budget? Color me intrigued and optimistic about the aviation engine's future, a bit more skeptical of its automotive prospects.

https://www.motortrend.com/features/...y-technologue/

[LAB3]

There's an awful lot of "Too good to be true" stories out there, thanks for clarifying!

[GS1150Pilot]

There's an awful lot of "Too good to be true" stories out there, thanks for clarifying!

It would be one helluva powertrain.

[Buffalo Bill]

Impressive. 1000 to 25,000 rpm, is that also the power band? Wondering what kinda transmission would work for vehicles.
With that high an RPM, maybe it will be used as a 2 stage electromotive propulsion?
That would greatly reduce battery size, and extend the range of electric vehicles.
I keep thinking of questions.
Use cleaner carbon fuels like: bio, propane, hydrogen?

[LAB3]

Someone has to actually build one out of something other than a computer screen first.

I'm not sure why exactly the idea electromotive power hasn't been developed more than it has but my best guess is the Zero Tolerance purists won out on that one. Now if they where to band together they just might be able to get congress to finally change the laws of physics, that's a lot of palm greasing right there and we ALL know who controls the grease supply.

[Buffalo Bill]

Someone has to actually build one out of something other than a computer screen first.

Skip to the 9:00 mark. They show a running prototype.

[LAB3]

Oh I didn't see that, gave up after two minutes of cartoons. Need more data, give it to Dulcich and Freiberger to feature on Engine Masters!

[Grimly]

Skip to the 9:00 mark. They show a running prototype.

A few brief cement dumper like revs before a couple of exhaust flashes then vid cut. I wonder if something broke.

[xkaes]

What they need is a good spokesperson.

I hear that Elizabeth Holmes is available!.

[bwringer]

Turbines or turbine-ish engines like this in cars and other 2D vehicles has been something of a holy grail for a long time. Maybe they'll finally pull it off, maybe not.

The intermittent combustion thing is different. Throttle response has always been an issue with continuous combustion turbines, so maybe that helps solve it?

The article and video are positively jam-packed with brutal ignorance (no, reciprocating motion is not inefficient), so it's impossible to tell whether this version actually addresses the issues in a realistic way.

The biggest physical issue is, of course, heat. And I see things in this design like large rubber seal, roller bearings, and sliding components that do not work well with large amounts of heat, or bode well for longevity. And, as mentioned, different materials in very close contact. All the above can be addressed to some degree with exotic materials and higher-precision processes, but these are brutally expensive. Plus, this "35 pound" engine is going to require far more weight and space than that for cooling systems.

Still early days, so who knows... piston engines have been under intense development for over 120 years. But then again, turbines have been under intense development for 90 years or so. Maybe they're on to something with this mashup.

[wymple]

A few brief cement dumper like revs before a couple of exhaust flashes then vid cut. I wonder if something broke.

And a very wet looking exhaust plume as well. No way that says efficient.