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Tuckerfan
03-29-2011, 07:44 PM
Said to be 3.5 more efficient than conventional engines. (http://gas2.org/2011/03/21/the-wave-disk-engine-cheap-efficient-clean-and-different/)
Developed by researchers at the University of Michigan, this small engine could be up to 3.5 times more efficient than the piston-driven engines found in most cars. How? Well the engine does away with those heavy pistons and replaces them with a single disk with small channels carved out to carry air and fuel…any fuel, from hydrogen to gas to biodiesel. The inside and outside edges of the disk alternately open and close to combine the air and fuel, and shockwaves produced from the rotation of the disk compress and ingite the combination. By hooking the engine up to a generator, you can produce electricity to feed the motor, while getting almost four times better gas mileage and producing 95% less carbon dioxides.

Judging by this pic:

http://c1.gas2.org/files/2011/03/wavedisk2.jpg

It looks like it wouldn't be too difficult make one using a fairly basic CNC mill.

Rich Carlstedt
03-29-2011, 09:06 PM
Looks to be a Tubine engine ?

feeds from the center to the OD ?

I don't trust any numbers without seeing how they are derived.
Rich

vpt
03-29-2011, 09:11 PM
My thoughts too. Looks like a big turbo or turbine.

A.K. Boomer
03-29-2011, 09:16 PM
Impossible efficiency ratings...


the piston engine is actually a great design and pistons do not "waste" energies like many believe they do --- they take energies to get moving from TDC to 90 degree's (max piston velocity) then at 90.0000001 degrees the piston starts its cycle of giving its energies back to the crank, same goes for BDC back to TDC, the only real loss in energies is bearing and oil friction and needed ring drag.

There's a reason why they've endured for such a long time, they are a perfect positive sealing devise, properly designed PE's can achieve well over 20,000 rpm's and that's far greater than most guys high performance milling machines.

The almighty piston engine also gets to take superb advantage of the burn rate of diesel and gasoline fuels just by the nature of the increasing piston speed to 90 degree's ---- by adjusting the bore and stroke and comp. ratio and now with variable valve timing and direct injection gas the maximum bang for the buck can be milked out of every power stroke,
It's all really about emissions anymore, if we did not have to worry about that then we would all be getting @ least 50% more efficiency than we are right now.

Tuckerfan
03-29-2011, 09:20 PM
Impossible efficiency ratings...
Bear in mind that its not a tech journal that the article's printed in, so accuracy on "detail matters" is unlikely to be high on their list.

J Tiers
03-29-2011, 09:28 PM
3.5 x more efficient than an engine which can be 40% efficient........... :rolleyes:

An engine only 3.5x more efficient, but it produces 95% less "carbon dioxides"..... :rolleyes:

D'yeh suppose maybe they meant "nitrous oxides" back before the scientific illiterates got hold of the subject?

One thing is fairly certain.... the article has proven to be a worthless source of information.

TGTool
03-29-2011, 09:36 PM
I say bogus - it won't even run. The article is pretty sketchy but from the diagram they have of the operation I don't think it has enough anything to create continuous rotation, let alone that kind of efficiency. 1. There's nothing there that I think will initiate a shock wave for compression. 2. If the fuel mixture ignites there's no expansion to drive rotation. 3. There's really nothing to keep some of the air/fuel mixture from leaving the exhaust ports compromising the efficiency they claim.

It looks like their force for rotation idea is that the curved flutes in the disk mean that the expanding gas will press harder on the concave than the convex side flouting all laws of physics.

There ought to be a Snopes site for engines and mechanisms.

Willy
03-29-2011, 09:47 PM
Well they've managed to garner a 2.5 million dollar federal stimulus grant, not sure at this point if that means it has potential or if this speaks about their ability to fill out grant forms. LOL

Note that the claims are that it could be 3.5 times more efficient, not that it is.

However a bit more info, a video, and some good points brought up on this page.


http://blogs.howstuffworks.com/2011/03/18/wave-disc-new-engine-design-from-msu-and-arpa-e-that-sounds-too-good-to-be-true/

A.K. Boomer
03-29-2011, 09:54 PM
Note that the claims are that it could be 3.5 times more efficient, not that it is.





It doesn't matter if they say it "could" or that it "is" either statement is impossible.

J Tiers
03-29-2011, 10:03 PM
Seven warning signs of bogus science.......

originally developed as a guide to judges, IIRC.

http://www.webexhibits.org/bogus/

gwilson
03-29-2011, 10:05 PM
Re: big grant money: Don't forget that big money from our taxes has been handed out for such research as "How long does it take to make breakfast",and "What time the frogs start croaking".

These are actual researches that were well funded. Don't forget what? $250,000 dollars for a TEAPOT museum(in N. Carolina,IIRC.

All you have to know is how to BS the idiots who might not have even read your grant request.

justanengineer
03-29-2011, 10:13 PM
I came to the conclusion long ago that grants with regard to science are for those who couldnt last in a proper research lab. Gotta love the dreaming dummies of the word...

+1 for big claims with no backing

Paul Alciatore
03-30-2011, 01:36 AM
Just exactly does "3.5 times more efficient" mean. If a conventional piston engine is 40% efficient, does that mean 40 X 3.5 or 150% efficiency? That is means you are getting more energy out of it than the fuel has to begin with.

So what does it mean? ?????

Essentially, it is a meaningless claim. You would be very hard put to raise the efficiency to 50% which would only be a 25% increase (or 1.25 times). I suspect the author has no knowledge of mathematics or how to use it.

Arcane
03-30-2011, 01:40 AM
Well they've managed to garner a 2.5 million dollar federal stimulus grant..........
Looks like the engine was damn efficient at getting grant money! Probably what it was truly intended to do from the start.

winchman
03-30-2011, 02:52 AM
I'll bet the major outcome of the research will be that more research needs to be done.

DougC_582
03-30-2011, 07:47 AM
I have no idea if the thing works or not, I can't tell from looking. Everything isn't obvious from just looking.

The "3.5 times as efficient" figure does sound inaccurate right away, but that could be a reporter copy error. If the creators had said that "it was more efficient, and that it created 3.5 times more power per-lb compared to a piston engine", both those claims would be quite believable for a turbine engine (the HP/lb figure would even be rather low).

Another thing I would note: the device claims to work off of "shock waves". Last time I checked the only way to create shock waves in air was to cause transonic flows.... so if this thing is dependent upon transonic flow to function properly, it would need to spin pretty fast to even hope to work at the level of efficiency claimed. And if that's true, then it has the same problem that conventional jet engines already have: since their compressor efficiency depends directly on the RPMs, they are essentially single-speed engines. They are rated for fuel consumption at 95% of their max RPMs, and suffer drastic efficiency losses at anything less than full throttle.

This is the real reason we still don't have new car dealers selling jet-engine cars today. It is certainly easy to build small turbines, a turbocharger is most of the way there already--but the low-RPM fuel economy problem remains.

JMS6449
03-30-2011, 09:02 AM
I do not trust "researchers say or "developed by researchers".

We were just involved in a conversation with a group that published a whitepaper article on a process that seemed commercially viable. When pressed, they could not say how they could produce the item yet stated a price per piece, the concept was flawed, and best of all had received grant money.

J Tiers
03-30-2011, 09:07 AM
Against the doubters, (and I am one) there is the fact that many of the very high efficiency furnaces operate in a way that could potentially be described by a reporter as "operating on shock waves".........