Wave Goodbye to the Internal Combustion Engine

March 17, 2011 10:05 AM

Michigan State University builds a prototype that would replace the internal combustion engine in automobiles. The wave disk engine runs on shockwaves, and would emit 90% less carbon dioxide, run at 3.5 times greater fuel efficiency, and weigh about 1,000 pounds less than a combustion engine system in a typical automobile.
posted by Rykey (89 comments total)

revolutionary!
posted by czytm at 10:11 AM on March 17, 2011 [2 favorites]

Gas consumption is quite... spartan.
posted by hal9k at 10:13 AM on March 17, 2011 [11 favorites]

I am shocked. Shocked, I say.
posted by weapons-grade pandemonium at 10:13 AM on March 17, 2011 [1 favorite]

The Wave Disc Engine sounds like something out of the future. Hey, are we in the future?
posted by Mister Cheese at 10:15 AM on March 17, 2011 [1 favorite]

Anyone know how this relates to the motor that some Russian oligarch recently (last year) invested 100 million into? I recall the Russian motor was like a reverse vacuum pump. This reminds me of it.
posted by Kinnishian at 10:16 AM on March 17, 2011

This...sounds great. But I've clicked around, and as far as I can tell they're at the "wall ornament" stage of the engineering process. Can anyone find a reference to where they've actually fired this thing up?
posted by Salvor Hardin at 10:16 AM on March 17, 2011 [4 favorites]

We are now... now. Now! Now! Crap... now it's the past.
posted by It's Raining Florence Henderson at 10:16 AM on March 17, 2011 [1 favorite]

It sounds a bit too good to be true, but I hope it's for real and the technology gets incorporated immediately.
posted by Skygazer at 10:17 AM on March 17, 2011 [1 favorite]

This sounds a lot like a Wankel rotary engine.
posted by DU at 10:18 AM on March 17, 2011 [3 favorites]

They would come out with this after my damn radiator blew.

stupid cars know when you're broke the thing looked like the right side of the titanic all i was doing was sitting in a parking lot the temp gauge didn't warn me cos the thermostat was broken too and this is why nobody will steal it
posted by cmyk at 10:18 AM on March 17, 2011 [2 favorites]

I'm pretty sure that in the future engines won't run on dead dinosaurs, so...not the future yet.
posted by etc. at 10:19 AM on March 17, 2011 [3 favorites]

It sounds like a variant of a Wankel rotary engine.
posted by Cool Papa Bell at 10:19 AM on March 17, 2011

Anyone know how this relates to the motor that some Russian oligarch recently (last year) invested 100 million into? I recall the Russian motor was like a reverse vacuum pump

Well, it probably didn't suck.
posted by hal9k at 10:19 AM on March 17, 2011 [2 favorites]

will replace nearly 1,000 lbs. of engine, transmission, cooling system, emissions, and fluids

Does it not need a transmission because it's only going in a Volt style hybrid? Or is that just bogus. Also, why doesn't it need a cooling system?
posted by aubilenon at 10:19 AM on March 17, 2011

jinx!
posted by Cool Papa Bell at 10:19 AM on March 17, 2011

There are some fantastic comments there, including a link to Newscientist and a paper on the device.
posted by Pogo_Fuzzybutt at 10:19 AM on March 17, 2011

Have they discussed this new engine with oil and gas companies? They probably have a few thoughts on this.
posted by Brandon Blatcher at 10:20 AM on March 17, 2011 [2 favorites]

This sounds a lot like a Wankel rotary engine.

Well, that sounds promising...
posted by Skygazer at 10:21 AM on March 17, 2011 [1 favorite]

NOT.
posted by Skygazer at 10:21 AM on March 17, 2011 [1 favorite]

Can anyone find a reference to where they've actually fired this thing up?

I don't think so. In the video the project lead says the $2.5 million ARPA-e grant is necessary for getting the prototype up on the test stand.

Have they discussed this new engine with oil and gas companies? They probably have a few thoughts on this.

Since it runs on natural gas I imagine they'd be quite pleased with it.
posted by jedicus at 10:21 AM on March 17, 2011

One of the comments on the article was quite good and reflected my thoughts (surprisingly).
This design does seem to be incredibly efficient at a certain rpm. Getting the engine up to that rpm shouldn't be that big of an issue, but maintaining it at that rpm giving varying loads *might*. Maybe there's some tricks you can do to make things work out, but it's not just a drop and replace for the internal combustion engine as the article implies
posted by forforf at 10:22 AM on March 17, 2011

Yeah, I'm a bit skeptical myself-- it's not a working automobile yet, after all. But for a non-science-y guy like myself, it seems like a step in the right direction. "The right direction" defined as "away from dependence on quite so much petroleum, and not so polluting," of course.
posted by Rykey at 10:23 AM on March 17, 2011

maintaining it at that rpm giving varying loads *might*

Presumably that's why it's a hybrid rather than direct mechanical drive.
posted by DU at 10:24 AM on March 17, 2011 [1 favorite]

This design does seem to be incredibly efficient at a certain rpm.

Maybe that's why it's a hybrid car engine. It just charges a generator, and isn't connected to a drive train.
posted by StickyCarpet at 10:24 AM on March 17, 2011 [3 favorites]

Good. It has been a while since someone has directed my attention to the new thing that will replace the internal combustion engine.
posted by jefficator at 10:24 AM on March 17, 2011 [11 favorites]

Go Green!
posted by alzi at 10:24 AM on March 17, 2011

As Muller says in the video, the concept is to have this running as a hybrid. It's a very efficent generator which recharges batteries. The car drivetrain would be electric. That allows the engine to run a maximum effiency.
posted by bonehead at 10:25 AM on March 17, 2011 [1 favorite]

That top comment by GoatGuy is good, explains the possible limitations.

It would certainly be good to see a more efficient engine, but rotary engines like the Wankel Rotary Engine and the Turbine Engine already exist: without a working prototype I'm a bit skeptical that they can solve all the practical problems of noise, sealing, cooling and a narrow range of power output.
posted by TheophileEscargot at 10:26 AM on March 17, 2011

The New Scientist article makes MUCH more sense. Using the engine to generate electricity for hybrids makes much more sense that using the engine to actually provide the power. BUT, that means the efficiency gains are mitigated by the efficiency losses encountered converting the mechanical energy to stored electrical energy, plus the losses encountered converting the stored potential energy to kinetic.
posted by forforf at 10:26 AM on March 17, 2011 [2 favorites]

The Wave Disc Engine sounds like something out of the future. Hey, are we in the future?

Well in 5 seconds and yes, we might be, I think. Here it comes. We're there! Oh wait, no that's the present. Wait, no, that's the past. Is it possible to be in the future? Where's Criswell when you need him?
posted by juiceCake at 10:27 AM on March 17, 2011 [2 favorites]

So does this bring my plans for a giant Wave Motion Gun on the front of my car closer to reality? Because if so, I'm excited.
posted by eyeballkid at 10:27 AM on March 17, 2011 [5 favorites]

...and weigh about 1,000 pounds less than a combustion engine system in a typical automobile.

I'm not a numbers guy, but the articles linked state that this system will lead to about a 20% weight savings over conventional engines. If 1,000 lbs is 20% of a conventional engine, then conventional engines would weigh 5,000 lbs.

I turn to WikiAnswers: The average weight of a car engine is 600 lbs, while the average car weighs between 3,000 and 5,000 lbs (for a van or SUV).

At any rate, this engine seems to be at the all-promise phase of the design process, before reality has its terrible way with it, adding unforseen complications, practical constraints, and efficiency-reducing compromises that will drag it down to the competitive level of a proven, fine-tuned existing technology. This isn't a comment on the premise in question - of which, I know nothing and understand little. But we've seen • it • all • before.
posted by bicyclefish at 10:29 AM on March 17, 2011 [2 favorites]

Shockwave Rider?
posted by GuyZero at 10:30 AM on March 17, 2011

Even assuming all the claims regarding this wave disk engine were true, the cynical side of me thinks that politics alone would prevent something like this from coming to market in a big way. Auto manufacturers have an entire infrastructure in place for building regular internal combustion engines, with a multitude of sub-contractors dedicated to that industry in turn. I imagine that doing away with bread-and-butter components like a camshaft, pistons, cranks, valves, and radiators (whuh?) might make auto interest groups fighting to keep the status quo.
posted by jnnla at 10:33 AM on March 17, 2011

It sounds like a variant of a Wankel rotary engine.

Probably not. The rotary engine is grossly inefficient as compared to the old piston models. My 1985 RX-7 had a 12A rotary that produced a pitiful 100hp and got at best 15 MPG.

I understand the efficiency of an internal combustion engine has something to do with the ratio of chamber surface area and compression. The rotary has a low compression and large surface areas.
posted by three blind mice at 10:34 AM on March 17, 2011

We need some kind of linear scale to measure the progress of these shiny new inventions so we can accurately come up with some level of enthusiasm. My first approximation of a scale looks like the following:

1) Vague daydreaming
2) Sketch on a cocktail napkin
3) Blueprints exist
4) No, really, blueprints exist on very large printouts as the output of some kind of CAD file
5) Has a shiny model
6) Claims to have a prototype
7) Someone has seen the prototype
8) Someone has seen the prototype do something
9) Someone besides a cousin's boss has seen the prototype do something
10) Venture capitalists and other funders have expressed interest
11) Venture capitalists and other funders have contributed more than $10,000
12) Independent, third-party verification of the prototype doing something
13) Another third party has measured relevant, interesting numbers from the prototype
14) Measured numbers do something better than what we already have
15) Cost projections of in-production units are both cheaper than what we already have and/or do something better, preferably both
16) Field testing shows the prototype does not collapse, burn up, or kill nearby people (unless that is what it is supposed to do)
17) Field testing shows the prototype functioning in desired purpose
18) Expression of interest by the United States Department of Defense
19) Assembly line for units created
20) IPO
21) Available to select customers
22) Available in market, like, you can go buy one

I'm sure I have left out some steps and odd side paths. I probably have the order a bit scrambled, too. Still, this sort of thing would let me know how seriously to take these breathless press releases.
posted by adipocere at 10:36 AM on March 17, 2011 [92 favorites]

It is most definitly not a Wankel engine. It's closer to being a kind of micro-turbine, a pulsed turbine, actually.
posted by bonehead at 10:37 AM on March 17, 2011

We're at now now.
posted by notion at 10:37 AM on March 17, 2011

Claims are overblown.
Progress is pre-natal.
posted by cman at 10:38 AM on March 17, 2011 [1 favorite]

That top comment by GoatGuy is good, explains the possible limitations.

I didn't make it past the part where he made it clear he hadn't read even the tiny blurb about the engine (i.e. he thought that "3.5x the efficiency of IC" meant it was an over-unity device.
posted by DU at 10:39 AM on March 17, 2011 [2 favorites]

A bit more detail, with links to a couple more papers here. That review paper linked above is quite good for the historical perspective on the development of these kinds of devices (still theoretical).
posted by bonehead at 10:40 AM on March 17, 2011

16) Field testing shows the prototype does not collapse, burn up, or kill nearby people (unless that is what it is supposed to do)

You mean like this?
posted by Xoebe at 10:42 AM on March 17, 2011 [5 favorites]

You mean like this?

More like this.
posted by 1970s Antihero at 10:45 AM on March 17, 2011 [1 favorite]

This claim of 60% efficiency in an automobile sounds bogus. 60% is about the best efficiency that can be obtained from combined cycle gas turbines. These use a gas turbine as the topping stage and a conventional steam turbine as the bottoming stage to extract as much energy as possible over the temperature range from input to output. You are not likely to get 60% efficiency from a single stage gas turbine due to the laws of thermodynamics.

It seems they may be confusing 60% efficiency when using the wave disk as the topping stage of a combined cycle electric generator plant. 60% efficiency used alone I think unlikely.
posted by JackFlash at 10:48 AM on March 17, 2011

It's nothing like a Wankel. A Wankel isn't that different from a normal engine - it doesn't have pistons, but it's still using a compression cycle similar to a normal engine, so it's still using the ideal gas law to set off the fuel, PV = nRT and all that. Using a shock wave means you don't have to compress all that gas so it could conceivably be far more efficient.

> This design does seem to be incredibly efficient at a certain rpm. Getting the engine up to that rpm shouldn't be that big of an issue, but maintaining it at that rpm giving varying loads *might*.

Reasonable point - if I read it correctly it's saying, "If the thing isn't rotating at the right speed then you don't get a shock wave," but if this thing is really 3.5x as efficient as a standard internal combustion engine, you have a lot of spare oomph to play with, and there are a lot of things you can do with differential gears or all sorts of gear-free "continuous transmission" systems IF you have power to burn.

Colour me "skeptical but I can't see anything immediately wrong with the idea, unlike 90% of the BS ideas that I read about new engines."

(Disclaimer: I'm not a mechanical engineer, just a skeptical guy with maths background.)
posted by lupus_yonderboy at 10:50 AM on March 17, 2011 [1 favorite]

This is obviously worthy of my furious mockery and derision sight unseen. And I can say that without so much as taking a peek at the article in the FPP because everyone knows that now that we have invented the incredibly subtle and sophisticated piece of tech known as the combustion engine, there is absolutely no way we could ever realistically develop anything better to replace it. That's just a consequence of the only truly universal law of technological progress: Any given tech only goes so far, and then arbitrarily stops there until everyone's finally done making money off it. That's what computer science predicts. Or something.
posted by saulgoodman at 10:51 AM on March 17, 2011 [5 favorites]

Oops, and I should add that a normal engine compresses the gas and then uses a spark plug to set it off, whereas a Wankel IIRC uses only compression to do it. This unit supposedly does neither...
posted by lupus_yonderboy at 10:52 AM on March 17, 2011

Scales like that exist adipocere. For example, TRL. I think I prefer yours though.
posted by Bugg at 10:54 AM on March 17, 2011

I understand the selling point of the Wankel is not in efficiency, but in faster response producing high torque at higher rpms. But I don't know for sure, could be just having a brain fart.

Looking into rotary engine efficiencies, I got totally and quickly sidetracked. Found out that there is something called a Rand Cam engine, and it's evidently being hawked by something of a snake oil salesman.

That doesn't have anything to do with this, other than to server as a cautionary tale. MSU is a reasonably credible, legitimate organization. But this may be a case of theory running ahead of implementation - and money frequently gets ahead of the implementation as well. MSU may not be immune to the fact that one of their professors is securing funding, expecially these days. It's a gamble I hope they win. Hey - it worked for University of Florida and Gatorade.
posted by Xoebe at 11:01 AM on March 17, 2011

What will replace the internal combustion engine
posted by jtron at 11:08 AM on March 17, 2011

What will replace the internal combustion engine

Cockroaches?
posted by It's Raining Florence Henderson at 11:09 AM on March 17, 2011

It sounds like a variant of a Wankel rotary engine.

As a couple other have said, I would compare this more to a small turbine engine with the compressor, combustion chamber, and turbine all smashed together into one spinning disk.

I have a feeling they're claiming the weight difference by proposing a design more like the Chevy Volt, where the engine only generates electricity for electric motors.
posted by backseatpilot at 11:11 AM on March 17, 2011

I have a feeling they're claiming the weight difference by proposing a design more like the Chevy Volt, where the engine only generates electricity for electric motors.

Does that feeling come from the article explicitly saying that?
posted by lumpenprole at 11:17 AM on March 17, 2011

I swear I read the article.
posted by backseatpilot at 11:18 AM on March 17, 2011

We need some kind of linear scale to measure the progress of these shiny new inventions so we can accurately come up with some level of enthusiasm. My first approximation of a scale looks like the following:

I'm not sure if I should feel enthusiastic or not about your scale, as it seems to only be at the napkin stage right now.
posted by blue_beetle at 11:20 AM on March 17, 2011 [1 favorite]

No, it isn't, blue_beetle. I'm at least #3. Go ahead and read the scale, the background is blue.
posted by adipocere at 11:24 AM on March 17, 2011 [5 favorites]

That death ray video is hilarious, Xoebe.
posted by storybored at 11:25 AM on March 17, 2011

the adiposcale: Might want to move #18 up around #8.
posted by benzenedream at 11:26 AM on March 17, 2011 [1 favorite]

The Wave Disc Engine sounds like something out of the future. Hey, are we in the future?

I don't know, let me go check the internet using the touch screen on my phone.

I'm sure I have left out some steps and odd side paths.

General Fusion is about a 12 on the Adipocerean scale, but their prototype is little and doesn't say much about the viability of a scaled-up version, since the physics may change significantly for larger volumes. That seems a lot different from what 12 is really meant to suggest. Maybe 5 would be more accurate. And maybe that scale should factor in whether the thing has been shown to at least work in theory. That seems like a big step before having a working prototype.
posted by Xezlec at 11:30 AM on March 17, 2011

Also, shouldn't 11 really be above 14?
posted by Xezlec at 11:34 AM on March 17, 2011

Hmmmm. You can do pretty nifty things for shockwaves, and in fact humble two-stroke engines with expansion chambers have been doing them for a while. However, I grow instantly skeptical when I hear "revolutionary" and "invention" in the same sentence. Some of the claims made about this engine are definitely too florid. Modern internal combustion engines, working at their optimum load, are already quite close to thermodynamic efficiency limits. The Diesel engine, in particular, is a tribute to the bloodymindedness of Rudolf Diesel to extract the last bit of work from its fuel. So, I can hardly see how such major improvements of efficiency may be obtained. Besides, I can see that this engine may share at least one big drawback of the Wankel engine:

The Wankel engine's terrible fuel economy is mostly due to thermal losses, because of the large surface of the combustion chamber. Much of the heat generated by combustion is thus lost to the engine block, rather than efficiently converted into work by the rotor. At first sight, this engine also has very much the same problem.
posted by Skeptic at 11:36 AM on March 17, 2011

Hey, are we in the future?

We are definitely at least in the beginning phases of the future.

So, flying cars, no; custom growable organs, yes.
posted by Civil_Disobedient at 11:36 AM on March 17, 2011

In every thread about a new engine design, people will bring up the Wankel engine.

Perhaps a game for mechanical engineers called "It's not the Wankel engine!" should exist.
posted by mccarty.tim at 11:50 AM on March 17, 2011 [2 favorites]

I'm not a numbers guy, but the articles linked state that this system will lead to about a 20% weight savings over conventional engines

I'm guessing that some of this goes beyond the actual engine; if the wave disk turbine engine thingy is simply producing electrical power, you can do away with the transmission/ transaxle part of the car as well, as each tire will get it's own motor. There's probably a bunch of other direct drive components that could be done away with as well.

Charitably assuming that this isn't all just vaporware, that is.
posted by quin at 11:51 AM on March 17, 2011

lupus_yonderboy: "Oops, and I should add that a normal engine compresses the gas and then uses a spark plug to set it off, whereas a Wankel IIRC uses only compression to do it. This unit supposedly does neither.."

Wankel does has the same thermodynamic cycle as any other gas engine - intake, compression, power, exhaust. It just doesn't have all the reciprocating mass of the pistons, drag from teh camshaft, etc. You're thinking of diesel, whereby there's no spark plug to initiate the power stroke - you compress the air/fuel to the point that POW it ignites on its own at just the right point.
posted by notsnot at 12:05 PM on March 17, 2011

adipocere: where's the part about the media breathlessly overblowing the tech with bad reporting before realising they've been had?
posted by Duug at 12:06 PM on March 17, 2011

adipocere: where's the part about the media breathlessly overblowing the tech with bad reporting before realising they've been had?

There's obviously room for either 3 or 8 more steps for the process. It can't be 22, that's not round enough, not official enough. Get it to a 25 or 30 step process and it will be more believable by the general public.
posted by Mister Fabulous at 12:12 PM on March 17, 2011

In the video, Mueller says it would be coupled with a battery pack for surges of power. I would expect that a powerplant like this would be best suited for an E-REV like the Chevy Volt. You'd want a large pack to draw from and store to, since I would expect you wouldn't want to turn this on and off frequently, and it doesn't have a wide efficiency band. Once it turns on, its committed to turning on and staying on for some length of time (15 minutes?). If you're in stop and go traffic it can put that energy back into the battery. If you're on the highway it'll just use the power it generates for propulsion.

It wouldn't work well in a PHEV (like the upcoming toyota prius plug-in) because most of those cars are only rated to about 60MPH on electric alone, so if you get on the highway you'd need to turn this thing on as you go above 60 and then if you hit traffic, it'll have to idle or turn off (it cant store the energy in a battery, as the combustion motor in the prius plug-in is linked to the ring gear in the planetary gear transmission system, you'd have to add clutches and a generator to the current transmission - which would make it look almost exactly like the Volt's transmission).

If they can get this working and scale it up to a reasonable power level (55kW for small cars, 100kW for SUVs/trucks), make it reliable, etc, it would make E-REVs much more efficient on the gasoline side (a Volt might get 70MPG on gas and 93MPGe on electricity). That said, they'll have to spend a lot of money to get there, and the momentum of ICE engines still may keep it out of the running.
posted by SirOmega at 12:17 PM on March 17, 2011

I can say with complete certainty that we all will be living the rest of our lives in the future.

The engine looks pretty cool to -- we really need an alternative.
posted by bricksNmortar at 12:21 PM on March 17, 2011

...weigh about 1,000 pounds less than a combustion engine system in a typical automobile...

I think this powerplant would be ideal for aircraft, since it appears to be lighter than air.
posted by Kirth Gerson at 12:22 PM on March 17, 2011 [4 favorites]

Or we could build cars with lightweight tube frames, dinky 30HP engines, a Saturn-style plastic shell, and have them designed to not have to go over 45 miles an hour.

People don't need to drive so fucking fast.
posted by dunkadunc at 12:35 PM on March 17, 2011 [6 favorites]

I'm still holding out for a swashplate engine in a kabineroller, myself.

As far as ultimate engines go, wasn't the Stirling cycle engine supposed to be that? Unless, of course, Popular Science lied to me in the seventies.

I do love the fact that that little expansion chamber in my scooter's engine works on sound wave principles, which makes a tune-up really about tuning it up...at least until you get your oil mixture wrong and soft seize (which is why my Stellamagoo is bone stock and pleasantly slow).
posted by sonascope at 12:35 PM on March 17, 2011

From the description, it sounds like the one big drawback is that engine rotational speed is critical. If the engine speeds up, some of the wave effects don't complete in time. If it slows, they complete too soon.

So you couldn't really use this the way a piston engine is used, with a direct mechanical drive train. You'd have to use it with a generator and electric motors on the wheels, the way a diesel locomotive works.

That, in turn, means that even if this engine is more efficient than a piston engine, you'd give some of that back because of inefficiency in the generator and motors. Transmissions and differentials are very efficient by comparison.
posted by Chocolate Pickle at 12:48 PM on March 17, 2011

Or we could build cars with lightweight tube frames, dinky 30HP engines, a Saturn-style plastic shell, and have them designed to not have to go over 45 miles an hour.

People don't need to drive so fucking fast.

There'd be added safety bonuses to slower, less powerful engines as well. But we freaking need the Hemi. Our merest desires to indulge our tastes for power-tripping Fahrvergnugen are really all that matter in this debate and it's totally worth dumping millions of gallons into the Gulf or Mexico and causing the dolphins in the Gulf to spontaneously abort their offspring in unusually large numbers for that. Not to mention the added social benefits of giving divers cancer.
posted by saulgoodman at 12:51 PM on March 17, 2011 [2 favorites]

Go Green!

Go White!
posted by pardonyou? at 12:54 PM on March 17, 2011 [1 favorite]

I would get so much fucking Fahrvergnügen out of a little dinky tube-frame car, you have no fucking idea. Those things could handle phenomenally.
posted by dunkadunc at 12:55 PM on March 17, 2011

When I was an undergrad, for a thesis project I built a radial-flow turbine engine. (Turbine where the working fluid enters radially, similar to how some pumps work. It has some interesting manufacturing-cost advantages over axial-flow turbines.) At first I thought that's what this was. It's not, at least it's not quite, but it's a bit similar.

I'd actually argue that it is a type of "internal combustion" engine, in that the fuel is being combusted inside the same chamber where you're doing the mechanical work, as opposed to something like a steam or hot-air turbine where you typically have a separate combustion chamber producing a pressure difference in a working fluid that you then exploit.

Still, I am betting that this is going to have rather strict operating regimes in order to get reasonable efficiency. Hard to say if there isn't even a working model yet, though. But I doubt you're going to want to couple this directly to the drive shaft of an automobile; it seems more like something that you'd want as part of a hybrid gas-electric system, use it as part of a genset.

But once you've done that, you've opened up a world of possibilities beyond the reciprocating 4-stroke Otto cycle that we all know and love, so I'm not sure that's really the competition. If you throw away the wide range of output speeds and torques, a typical car engine isn't an obvious winner (except that you can go out and buy one today). There are designs like the two-cycle diesel engine (which you can add water injection to, if you like, achieving something like a six-stroke engine with only 4 strokes / cycle, and eliminate much of the cooling system).

The bigger story is that hybrid vehicles are going to make it much easier to play with different engine designs, since you are really just dropping in a generator powerplant that only has to operate at a fixed RPM. I hope this particular design lives up to its inventor's promises but even if it doesn't, there are a lot of other interesting designs lurking out there which each have their advantages.
posted by Kadin2048 at 1:04 PM on March 17, 2011

Wikipedia's rotary engine page has a list of engines at the devel/prototype stage. Most have been there for years or decades. Making a better engine is hard.
posted by bystander at 1:14 PM on March 17, 2011 [1 favorite]

No working prototype?
Seriously?
Because without one the good Professor appears to have invented The Pinwheel.
posted by Poet_Lariat at 1:34 PM on March 17, 2011

I would get so much fucking Fahrvergnügen out of a little dinky tube-frame car, you have no fucking idea. Those things could handle phenomenally.

Fahrfuckingvergnügen?
posted by Mental Wimp at 1:54 PM on March 17, 2011

We need some kind of linear scale to measure the progress of these shiny new inventions

There is a recognised Technology readiness level scale, but yours is better.
posted by Canard de Vasco at 5:31 PM on March 17, 2011

You want some fahvergnoogies from an electric car? ANd this is from 2007!
posted by Redhush at 5:58 PM on March 17, 2011

"So you couldn't really use this the way a piston engine is used, with a direct mechanical drive train. You'd have to use it with a generator and electric motors on the wheels, the way a diesel locomotive works."

So you didn't read the article, the comments on the article, or the comments here?

Interesting.
posted by sneebler at 6:07 PM on March 17, 2011 [1 favorite]

Hurry up!
posted by Defenestrator at 6:32 PM on March 17, 2011

So you couldn't really use this the way a piston engine is used, with a direct mechanical drive train. You'd have to use it with a generator and electric motors on the wheels, the way a diesel locomotive works.

I'm pretty sure that's what the guy said it was meant to do.

Prediction: it will work, but even though it will use less fuel (or extract more energy out of the fuel), it will do so in a less clean manner. Lots of oxides of nitrogen or something.

Modern internal combustion engines, working at their optimum load, are already quite close to thermodynamic efficiency limits. The Diesel engine, in particular, is a tribute to the bloodymindedness of Rudolf Diesel to extract the last bit of work from its fuel. So, I can hardly see how such major improvements of efficiency may be obtained.

1- They are almost never in that optimum load range. If you look at a BSFC chart, the optimum load is almost always chugging at 2000-ish RPM with a wide open throttle.

2- If they are at their thermodynamic efficiency limits, why do they need cooling systems? The radiator and the hot exhaust are all the energy in the fuel being wasted.

Besides, I can see that this engine may share at least one big drawback of the Wankel engine:

The Wankel engine's terrible fuel economy is mostly due to thermal losses, because of the large surface of the combustion chamber. Much of the heat generated by combustion is thus lost to the engine block, rather than efficiently converted into work by the rotor. At first sight, this engine also has very much the same problem.

It appears that the engine is like a turbine in that effect- the heat helps propel the rotor along. But it's like an IC engine in that the combustion happens against something, which is also the turbine.

The professor hopes it will be the best of both worlds. I hope he's right.
posted by gjc at 7:32 PM on March 17, 2011

I can say with complete certainty that we all will be living the rest of our lives in the future.

But Sisko, according the Prophets/Worm Hole Aliens, lived in the past, at Wolf 359. Other may live in the past in a like manner...
posted by juiceCake at 9:20 PM on March 17, 2011

ARG! Right, it's diesel that doesn't have spark plugs. Excuse: tiredness and all. Bah!
posted by lupus_yonderboy at 2:33 AM on March 18, 2011

The Wave Disc Engine sounds like something out of the future. Hey, are we in the future?

Not yet. Tomorrow.
posted by krinklyfig at 4:23 AM on March 18, 2011

We need some kind of linear scale to measure the progress of these shiny new inventions so we can accurately come up with some level of enthusiasm.

For defense related tech, theres this and this.
posted by jpdoane at 7:57 AM on March 18, 2011