New rotary engine

[rtoldman]

For those who know about these things...

Just read the commentary on TheDrive about liquidpistons new rotary engine
thedrive.com
liquidpiston.com

It looks really cool but is it something that we will start seeing or is it a solution looking for a problem? I want one... just because

[kdahm]

It's a solution looking for the problem.

1. While it does address the apex seals, it doesn't do anything for the problem of wiping on the sides of the rotor.
2. Speaking of the apex seals, they'll still need lube oil at the tip, meaning that there's more oil burning going on.
3. Their small 43 lb engine with 25 hp gets to be that way by supercharging. Supercharging a small diesel will also greatly improve it's performance.
4. There's a lot of hype and not a lot of torque curves going on. What's the performance when naturally aspirated? What's the specific fuel consumption (lbs fuel/hr/hp/lb engine).
5. What's the expected maintenance schedule?

I can see really only two uses for this thing. Ultralight aircraft or torpedoes. Or I suppose it could be used for drones.

[Pdf27]

It's a niche product for customers who need a high power density (i.e. very light), heavy fuel engine. I think the fact that they have a banner ad at the top of every page saying "click here to become an investor" tells you everything you need to know about how niche their product is likely to be. If it was as good as the hype suggests, someone would have bought them out for megabucks by now.

[Nik_SpeakerToCats]

Like a basic Wankel or two-stroke, it will have impressive power/weight, but indifferent efficiency.

Supercharging such will seriously increase efficiency and altitude tolerance, but at the expense of complexity and up-front cost.

Also, those seals: Okay, they've learned a few tricks from Wankel's battles, but such specialised seals become expensive 'routine consumables'...
$$ parts, $$$ labour...

Plus, with growing emphasis on pollution mitigation, the market for such niche designs is rapidly narrowing.

Would it suit a 'throw-away' such as drone or torpedo better than a generic design ?
Would it be an 'ideal' match to a hybrid vehicle ? An 'off-grid' generator or pump ??
Um, probably not...

Here's a fun page:
http://www.douglas-self.com/MUSEUM/POWE ... lICeng.htm

[rtoldman]

It's a solution looking for the problem.

1. While it does address the apex seals, it doesn't do anything for the problem of wiping on the sides of the rotor.
2. Speaking of the apex seals, they'll still need lube oil at the tip, meaning that there's more oil burning going on.
3. Their small 43 lb engine with 25 hp gets to be that way by supercharging. Supercharging a small diesel will also greatly improve it's performance.
4. There's a lot of hype and not a lot of torque curves going on. What's the performance when naturally aspirated? What's the specific fuel consumption (lbs fuel/hr/hp/lb engine).
5. What's the expected maintenance schedule?

I can see really only two uses for this thing. Ultralight aircraft or torpedoes. Or I suppose it could be used for drones.

might be a silly question but is the wiping action of the rotor anything like the tip clearance issue in jet engine rotating components where it rubs when cold and gains clearance when hot but any clearance is loss?