I saw this on the newsfeed this AM. I haven't seen any posts on this and wonder how that's possible. Seems pretty intriguing. Jalopnik had a bit more info on it with links, so hopefully it's okay to link there. I'd think there would be a huge initial market for lawn equip with additional market for EV applications down the road, as they are shooting for.
Now granted I literally just woke up, I'm still in bed. But how the hell is this thing doing its thing? I get its a rotary engine spinoff. But what's the blue crap going into the rotor things?
It looks like its essentially a rotary but with three different combustion chambers. The inner rotor is acting as an intake manifold / intake distributor. The blue stuff is the intake charge.
I really don't see how this will not suffer some of the same issues as a normal rotary since the large high surface area combustion chamber is said to be a primary source of issues. Not to mention the still present side and apex (of some sort I am sure) seals.
aircooled wrote: It looks like its essentially a rotary but with three different combustion chambers. The inner rotor is acting as an intake manifold / intake distributor. The blue stuff is the intake charge. I really don't see how this will not suffer some of the same issues as a normal rotary since the large high surface area combustion chamber is said to be a primary source of issues. Not to mention the still present side and apex (of some sort I am sure) seals.
Yea, I see it as an inverted version of the rotary. Including moving the seals from the moving parts to the sides.
alfadriver wrote: Yea, I see it as an inverted version of the rotary. Including moving the seals from the moving parts to the sides.
I wonder if this makes it easier to have a more durable seal design? Or maybe allow for thicker seals that are spring loaded into position somehow (to adjust for wear over a longer period before needing replacement)?
My understanding is that they were trying to find a way to get a better combustion chamber shape vs the standard Wankel design.
38 seconds into the go-kart video, you can see what engine management it's running. 
In reply to MadScientistMatt:
Funny thing is- I don't see that it's a better shape. At least for what I see as the major drawback to the wankel design- there is still a large amount of surface area for unburnt HC's to hang around in.
While the cartoon shows a tiny burn chamber, it misses the problem that the surfaces don't touch other than the seal- so that whole gap will still have something there.
I wish them luck, though.
Might be one of those things that works well or well enough on a small engine, but less well on a larger engine. Like the little model air plane engines having no piston rings. A small version of this engine might not need any seals.
I thought it was interesting that the recent model has numerous cooling fins while the earlier prototype does not, and wondered if they found out it needed better cooling after some catastrophic event. I know nothing about magic spinning triangles, so I can't armchair QB its design, but I surely hoped others here would. Thanks!
Interesting, could make a good APU/range extender for series hybrids.
klb67 wrote: I thought it was interesting that the recent model has numerous cooling fins while the earlier prototype does not, and wondered if they found out it needed better cooling after some catastrophic event.
I think that was more of a running proof of concept engine, kind of like their earlier/larger diesel engines were. They had no cooling system, because they weren't really intended to run hard/long enough to need it.
I've been loosely following them for a while now. Here is the direct link people can follow to their website, with more detailed information: http://liquidpiston.com/
rslifkin wrote: I wonder if this makes it easier to have a more durable seal design? Or maybe allow for thicker seals that are spring loaded into position somehow (to adjust for wear over a longer period before needing replacement)?
Mazda's designs are spring loaded, too.
I don't see this solving the major issue with Wankels, namely all that internal space and horrible combustion chamber shape. (Same problem from two different viewpoints) What goes in must get burned quickly and completely... ain't gonna do that with any kind of moving chamber design.
So I'm told the intended use is low HP, low weight. They have DARPA money I think. Think tiny little gas-powered generators that make as much electricity as a really big piston-motor generator.
Here's the pitch on its efficiency:
The basic idea is similar to a Wankel rotary, but turned on its head. Where the rotor holds the seals in a normal Wankel, the housing does that job in the X1 engine. This allows significant reduction in oil consumption over a regular rotary motor. Other enhancements include direct injection, a high compression ratio at 18:1, and a dramatic change to the geometry of the combustion chamber, which maintains a constant volume during ignition. This change means the air-fuel mixture auto-ignites like a diesel, and can be burned much longer than normal. The result is a more complete combustion ending in low emissions and very high chamber pressures. This high pressure is allowed to act on the rotor until it reaches nearly atmospheric pressures, so almost all the available energy is extracted before the exhaust is physically pushed out. Again, this is different than a normal internal combustion engine, which releases very energetic, high-pressure exhaust gas.
Notice the one in the video is bolted to a motor to run it, because it doesn't, you know, work.
JBasham wrote: So I'm told the intended use is low HP, low weight. They have DARPA money I think. Think tiny little gas-powered generators that make as much electricity as a really big piston-motor generator. Here's the pitch on its efficiency: The basic idea is similar to a Wankel rotary, but turned on its head. Where the rotor holds the seals in a normal Wankel, the housing does that job in the X1 engine. This allows significant reduction in oil consumption over a regular rotary motor. Other enhancements include direct injection, a high compression ratio at 18:1, and a dramatic change to the geometry of the combustion chamber, which maintains a constant volume during ignition. This change means the air-fuel mixture auto-ignites like a diesel, and can be burned much longer than normal. The result is a more complete combustion ending in low emissions and very high chamber pressures. This high pressure is allowed to act on the rotor until it reaches nearly atmospheric pressures, so almost all the available energy is extracted before the exhaust is physically pushed out. Again, this is different than a normal internal combustion engine, which releases very energetic, high-pressure exhaust gas.
Then post the numbers and targets. Hp/lb and expected operational RPM. You can make a lot of motor designs run very efficient at one specific RPM that is for sure.
wearymicrobe wrote:JBasham wrote: So I'm told the intended use is low HP, low weight. They have DARPA money I think. Think tiny little gas-powered generators that make as much electricity as a really big piston-motor generator. Here's the pitch on its efficiency: The basic idea is similar to a Wankel rotary, but turned on its head. Where the rotor holds the seals in a normal Wankel, the housing does that job in the X1 engine. This allows significant reduction in oil consumption over a regular rotary motor. Other enhancements include direct injection, a high compression ratio at 18:1, and a dramatic change to the geometry of the combustion chamber, which maintains a constant volume during ignition. This change means the air-fuel mixture auto-ignites like a diesel, and can be burned much longer than normal. The result is a more complete combustion ending in low emissions and very high chamber pressures. This high pressure is allowed to act on the rotor until it reaches nearly atmospheric pressures, so almost all the available energy is extracted before the exhaust is physically pushed out. Again, this is different than a normal internal combustion engine, which releases very energetic, high-pressure exhaust gas.Then post the numbers and targets. Hp/lb and expected operational RPM. You can make a lot of motor designs run very efficient at one specific RPM that is for sure.
And emissions numbers- just the basics HC, NOx, and CO in PPM.
I see the changes to try to be advantages, but it's still a big surface area.
I think DI is a better fit than for a normal Wankel design- as the locations are more compact.
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