Generators

[fsarcone]

https://www.liquidpiston.com

A very interesting new engine. The military is interested & will give them a boost. Their generator will take up a fraction of the space my current 7kw generator occupies. Hope they move into marine & RV soon.

 

[Shrew]

They say it's not a Wankle, but it sure looks like that was the platform their design started with.

 

[Pau Hana]

Following...

 

[DavidM]

It uses some of the principles of a Wankel, but it has an eccentric drive shaft that makes the rotor circumscribe a rotating path different from a Wankel. Seems that it still uses the lobe seals that were one of the problems with the Wankel engine.

It is light, compact, but sure requires lots of precision machining which won't be cheap.

I don't see it going mainstream due to production costs, but it might work fine in high value military drones, but not your lawn mower engine or your boat's generator.

David

 

[JohnEasley]

Interesting. Worth following to see how this new take blossoms... or not.

 

[Ski in NC]

Shares a lot of features with the Wankel, that will include some of the good parts and some of the bad parts.

The good: Small package, probably good balance, less weght.

The bad: Hard to seal gas exchange ports, need total loss lubrication like a two stroke gasser. Bad for emissions.

Cooling issues- rotor with gas ports is dealing with hot exhaust gasses, will play havoc with lube and sealing.

Thermal efficiency- lots of surface area exposed to combusted gasses, this saps heat and thus lowers efficiency.

As a package, I don't see it being much more successful than the Wankel/Mazda rotary.

I'm a bit of a student of these alternative engine designs. Right away I see the shortcomings of the designs, then I read further and it seems more of an effort to grab up govt R&D money (especially from the military, which may have a use). R&D funds a nice facility, finances the absolute fun that gearheads have with these, and gives them some coin too.

They have been working on this since 2003 and no real evidence of solid dyno runs showing performance, efficiency or durability.

I would not hold my breath while waiting for this to hit the market.

 

[sbman]

It looks like they have some advantages over the Wankel engine, especially in that the rotor tip seals are gone, it's using seals fixed to the crankcase which can be lubed from passages in the casing.

As Ski pointed out it has other drawbacks, but I could see it having uses in areas where lightweight is the primary design goal.

 

[FF]

I have been following this engine for a while.

The promise of a 1 pound per HP , at cont. output will change cars, boats, aircraft and gen sets.

The ability to burn most any fuel should delight the used engine oil folks.

 

[Iggy]

They say it's not a Wankle, but it sure looks like that was the platform their design started with.

Thats what I thought. Mazda years ago had a car with one. a good engine but low MPG.

 

[OldDan1943]

Hmmmm, who's Congressional district?
The Feds never seem to run out of money for bad ideas and unproven technology.

 

[sunchaser]

As Ski mentioned, emissions for this type of design are a relevant concern. Lost in all the anti fossil fuel noise are the marvelous improvements in gasoline engines and vehicle designs. Electronics, injection systems and power output per CC I find amazing.

We are about to celebrate the 100th anniversary of Mr Winton's 2 stroke engine design. This 1920's design, by serendipity, was to be found in a boat GM's lead designer and engineer Charles Kettering cruised. He mentioned this boat engine to Alfred P Sloan who said "let's buy the Winton Company." Thus was rebranded the DD two stroke diesel.

New designs can be around for awhile moldering away, just saying ---

 

[bugmonster]

Thats what I thought. Mazda years ago had a car with one. a good engine but low MPG.

Depends on which Mazda you're talking about. Had an '86 RX7 - ran fantastically, even if low torque. Never had a problem with it.

Later had a ~'05 RX8. Nothing but problems. Was in the shop probably 25% of the time I owned it. Finally Mazda agreed to replace the engine. I sold it from the shop's lot, never drove it again. Heard there were a lot of the RX8 generation with issues. Not so many problems with the previous generation (RX7).

 

[FF]

The surface area of the combustion chamber is one source of "pollution",the Wankel has a large area exposed to combustion so had problems with Air Police.

This engine is an inside out Wankel, but new exhaust cleanup methods might solve the problem.

If not, at least under 100HP engines may be permitted .

Many trawlers cruise on 40-60 hp which would be very compact and under 100lbs..

 

[lwarden]

From my mechanical engineering background I would suspect the seals to be the main disadvantage to this engine design, just like the Wankel. Probably good for something like a model aircraft that has short run times and life, but I don't see it for a generator.

I've got several friends working at Achates Power here in San Diego and their opposed piston design is showing very good efficiencies in both diesel and direct injection gas and would make a very good generator engine. The military has been sponsoring several programs but they now have interest from the larger engine manufactures so the hope is to have it commercialized in a few years.

https://achatespower.com/about-achates-power/

 

[Fletcher500]

I had a Wankel in a small Mazda truck in the late 70’s. Smoked like hell until it warmed up.

Just briefly scanned their website, and their funding history. They appear to be hitting their funding goals but some of the points brought up here give me pause to jump in.

 

[Ski in NC]

That Achates OP engine looks pretty far along in development.

Read through some of their technical paper from their site, read a bit more like sales pitches than solid tech!! But they were written by Achates employees, so somewhat explained.

They went into detail about lube oil control on a ported two stroke, and claimed that they got lube oil consumption down to what was typical of a 4s. Good for them!! But the problem then is (like faced by Detroit Diesel over many decades of refinement) by keeping lube oil under such tight control, the compression rings tend to run dry and scuff.

On a DD you want some lube oil use or you will be doing cylinder kits before you should. And on a DD they don't have exhaust ports in the liner, they use valves. Same as big ship 2s diesels. There is a reason they went away from (very hot) exhaust ports in liners. But you can't do that on an OP engine.

 

[sparky66]

Add this to the list of "revolutionary" engine designs that never materialized. If they can't have a working(as in doing an actual application) motor after 17 years of development, then I predict this is going nowhere. Model airplane engines don't count.

 

[markrkrebs]

The seals are fixed and can thus be fed lubes oil which should help. Lightweight! ... not critical for boats...

 

[Bill & Stella]

Masda has been working on a Wankle off-shoot to be used as a range extending genset in their new hybrid. Maybe this is related??

 

[FF]

While noodeling gas or diesel engines is always fun, the big bucks are in battery research.

1,000 miles on a charge ? That's what some tout.

While an electric car might be fine , the real push seems to get some of the bucks Tesla is earning.

No its not in selling cars , Tesla lost 66 million last year doing that, its selling indulgances to the auto makers with gas hogs,they earned by selling electric cars.

Tesla made about $370 million on forgiveness credits.

I am sure that is a cash flow the rest of the auto makers see as a huge prize.

If we do switch to electric cars, coal and nuke electric generating stocks should rise.

They will all need to be charged,somehow.

 

[OldDan1943]

They will all need to be charged,somehow.

And that is the part folks do not understand.
It is merely a relocation of the pollution making plants.

 

[PMF1984]

I’m still waiting for an affordable fuel cell where the “fuel” is available.

 

[Portage_Bay]

And that is the part folks do not understand.
It is merely a relocation of the pollution making plants.

I see some advantages to as you say the "relocation of the pollution making plants". But they are not implemented yet and may never be. Each car burning it's own hydrocarbon fuel distributes the pollution. All of the cars world wide spread the pollutants around the globe. On the other hand generating plants localize the pollution in a much smaller number of places. In theory all of the pollutants can be captured and dealt with.

Another advantage to electric vehicles has to do with the source of the energy. An engine that burns hydrocarbons is pretty fussy about what you pour into it. You can't burn gasoline in a diesel engine for example. When you're "burning" electricity to power your car it doesn't care what was used to generate the electricity. As the world begins to shift away from fossil fuels electric vehicles won't be left in the lurch.

All of that is nice theoretical speculation. And for now that's all it is. Right now the best we have is clean burning engines properly maintained and operated.

Another possible advantage is that I expect electric motors to be longer lived and require less maintenance than internal combustion engines. That will probably be offset by the aging of the batteries and electronics that make an electric car work.

Whether we like it or not electric propulsion of vehicles and to a much lesser extend boats/ships is on the rise.

 

[Woodland Hills]

And that is the part folks do not understand.
It is merely a relocation of the pollution making plants.

It is cheaper and easier to clean and monitor the emissions of a single power plant as opposed to 20 or 30 thousand vehicles. For one thing you won’t have a power generation station chipped by its redneck owner to be able to “roll coal” unless you live in Texas!

Also it won’t be long until the last coal fired generation plant is abandoned for cleaner natural gas and even cleaner wind or solar. Nothing to do with emissions m: coal is too damn expensive compared to fracked natural gas.