Quasiturbine, the Motor of the Future?

I suspect that the thin shape of the moving combustion chambers lends itself poorly to fuel/air mixing and flame-front propagation. This leads me to guess (but only a guess) that it might not burn very cleanly.

There was some quaint verbiage in these reports. 1. "A small amount of air and fuel produce an incredible amount of energy." Not so; the amount of energy is calculable and quite credible. 2. The window saying "reporting has been suspended...." 3. The statement that it might take decades before this becomes competitive. That's understandable, but then what's so hot about this? 4. Few moving parts. [?] That daisy-chain of linked members is not exactly simple.

In the early wankel engine the rotor tips kept burning out also the seals on the sides of the rotor caused problems.

I drove one of the early NSU Ro80 models and it was weird to drive compared to a piston engine, there was inside the car very little noise and i was alerted by a buzzer that was telling me that 60 mph i was over reveing the engine at about 13000 rpm.

the gear change was a semi auto a weird system in that it had a normalish mechanical clutch that would dis engage when you touched the gear stick you had to take your right foot of the gas as you would on a normal manual, and select a gear.

i could never understand why you want such a crazy system that wasnt auto and and wasnt manual.

the ignition system at the time would give a fatal shock if touched which was unheard of then, it also had special spark plugs and had two to ensure good burn,they were a pig to tune and the engine was also very heavy for a two rotor engine, other wise it was ok i suppose.

oh and the fuel economy was rubbish at approx 25 mpg

I seem to remember a design for an engine using up to 40 pistons in a sort of rotary set up that was featured on Tomorrows world probably late 70s early 80s. It was promised as a better balanced more efficient engine set up but I never heard any more about it! I have always thought there must be a better way but what is it?

A word of caution about "A non-substantiated opinion"

Talking about new engine, one should resist the temptation to expose his know-how on the Wankel and conclude (without specific argument) that it does apply to Quasiturbine or other engines. That is not a practical assessment methodology. Proposing an innovation is always a pretentious gesture, but putting the inventor arrogance aside, the technology could be a positive step which deserves careful attention before commenting.

It is always great to read from knowledgeable people about Wankel, but even more interesting after they take the time to read also about the Quasiturbine differences at http://quasiturbine.promci.qc.ca/ETheoryQTVersusWankel.htm . Thermodynamic of Wankel is poor (for one) because its chamber is unable to gather all the mixture in one cup (rather keep it spread all over), while QT do gather all its mixture in the cup, as all the modern piston does. The surface area to volume ratio is standard in QT-SC (without carriage) and irrelevant in the detonation QT-AC series (with carriages).

There are many things inherently "inefficient" about pistons (not necessary mislead), take the time to read http://quasiturbine.promci.qc.ca/ETheoryQTVersusPiston.htm . Large diesel ship engines are stunningly efficient, at over 50%, an efficiency which can be match with other clean engine concept. Notice that engine efficiency in detonation engine will be very high, even in small size engine (I agree it is not ready for market yet...).

The development of the Wankel is in deed instructive, but again does not necessarily apply to other engines, in other times. Today, what is fashionable is electrical motors: Like food (it is great, but people do not care how it is made, and where it is coming from), electricity is great, but people do not care how it is made and where it is coming from. Billions of $ in hydrogen and fuelcell as been a strong diversion signal, against the engine developpers. Synthetic fuel of the future has also been ignored. Unfortunate, Quasiturbine and modern engines are much about how and where, which is too basic to be fashionable!

Even if some alternate engines "answer" non-existent problems, this is no reason to generalize to the Quasiturbine. Ignorant can make any conclusion for fun, but when someone take the time to introduce himself as some kind of an expert, then only substantiated conclusions are fun and constructive (or to the point destructive) to read. Expert's un-substantiated opinion should be stated as such - no obligation to like or be positive of any technology of course.

Keep having pleasant posts. Amicalement,
Gilles info@quasiturbine.com

That, and the link, were pretty humorous. Marketing hype is such a fine art....

A word of caution about "A non-substantiated opinion"

I think it goes without saying that what I said was my opinion. Whether it is substantiated or not can be seen from a review of the literature on alternative engines: there have been dozens, and not one has shown significant, marketable advantages over the piston engine for automotive use. The Mazda Wankel is the only one that has come close, and even that has required millions of dollars of development. The NSU Wankels were, effectively, failures. Likewise the Suzuki Wankel motorcycle.

I have looked over your website, and have watched your air-powered go kart in action, and it appears that it might perform about as well as other air-powered vehicles. I have no reason to believe that a standard vane motor would not perform as well or better. One can conclude nothing at all re the value of a Quasiturbine as an engine from the go kart's performance, nor can one conclude anything re its effectiveness as as air motor. You'd have to supply precise, verifiable performance data to sell the design as an air motor (let alone as an engine).

A good proof of concept engine would give your project some credibility. A go-kart, powered by air, does not help, because various air motors are already available. There are many fundamental differences between air motors and engines. "The proof is in the pudding" as we say.

These days, for an engine to be successful against the piston engine, it must offer better specific fuel consumption. Chain saw engines are already light enough that there is not a crying need for lighter chain saw engines: you want the weight of the saw to do most of the work. But suppose there were. Then, the only thing that will convince anyone that your invention is an improvement over the current state of the art is a real engine, that produces more power per pound and more output energy (hp-hours, or kilowatt-hours) for a given amount of fuel.

Until your website provides meaningful information on brake specific fuel consumption from actual tests, anyone evaluating the engine is likely to say that is seems very similar in principal to a Wankel, with a very large ratio of surface area to combustion chamber volume (but with a much more complicated rotor). Therefore, the expectation is that thermal efficiency would be low. Your website does not clearly make a case for improved thermal efficiency. Unlike a Wankel, however, which has a one-piece rotor, yours is made of a many pieces which must articulate for the engine to function. Your website does not make a clear case for the offsetting benefits. If you could say, yes it is complex and more difficult to machine, but it is lighter and has better thermal efficiency than a piston engine, then your chances for commercialization would be better, I'd think.

Given limited financial resources, it would be better, I think, to spend your money on real engine development, rather than on air-powered go karts -- seeing a go kart move under air power is profoundly underwhelming, and says no more about your design as an engine than it does about using a vane motor as an engine would.

Why avoid the obvious step of developing a real proof of concept prototype. Skeptics will say, "Why not show how the engine performs? What is he trying to hide? Why the air powered go kart distraction?" Until I see real dyno testing of a lab engine, all the marketing hype has no meaning.

Obviously, this is all opinion, but that's all we have until we have actual test data. I hope you can construct a real prototype and publish such data. You might also work on simplifying your website, so that it deals with just a couple clear, supportable benefits. I wish you luck with this project.

Bonjour,

I like what I now read .
Essentially, you don't know (or are not sure) and are waiting to see the test results.
Meanwhile, substantiating your points is not need.

Fair enough. Merci, Gilles

P.S. - I will keep the website complicated (educational) for a while
for those whom ideas have value and interest much before test result and marketing.
Frendship is for those who can wait - I will.

GA! (Blink and EW)

I don't see any reason the QT would have any significant benefit over the standard air motors available today:

http://www.gastmfg.com/airgearmotors.html

The simplicity of design and construction of the vane type motor is one reason they have been so successful in their particular market.

A QT developed into a practical combustion/detonation engine might have some benefits on paper. We need to see "working" and testable prototypes with solid reproducible data. Even if working prototypes measure better than current engines, the design will still fail and fade into obscurity (like so many others) if it cannot be economically mass produced.

Quasiturbine publishes « efficiency data » while vane motor manufacturers don't. Premium on « efficient equipment » is rapidely recovered in operational cost.

Unlike vane pumps or motors, which vane extension is important and against which the pressure acts to generate the rotation, the Quasiturbine contour seals have a minimal extension and the rotation does not result from pressure against these seals. The vane geometry does not allow high compression ratio at TDC (top dead center), while Quasiturbine does, and this is why QT is efficient (less pressure charging losses), and this is why there is no vane combustion engine.

Salutations, Gilles

An additional comment: Efficiency has direct consequences on scalability: Non efficient small motor (up to HP ?) could be very practical as the energy lost may not be cost significant. However, large units have to be very efficient as energy lost would be costly. This is why Vane motor are not scaled up as the Quasiturbine is. Furthermore Vane motor are difficult to scale up as pressure force on the vanes become excessive, and limit their radial movements.

Fortunatly, not everyone is negative about Quasiturbine. Even if it may not be convincing to everyone, here is recent Vidéo by University of Connecticut - Quasiturbine in « Brash Vehicle Propulsion System »
www.youtube.com/watch?v=xZCj6yewtQ0
www.quasiturbine.com/QTVideos/CocuzzaSteamQT100419.mp4
Photo at : www.brashengines.com/FAQ.html

Amicalement, Gilles www.quasiturbine.com

Sorry, previous dead video link has been replaced by:
http://www.youtube.com/watch?v=Ah5gAENMrKs

University of Connecticut -
Quasiturbine in « Brash Vehicle Propulsion System ».
A project supported by the US Department of Transportation
(John Volpe National Transportation Systems Center in Cambridge MA)
exploring the use of BRASH™ technology for large vehicles,
such as mass transit vehicles.
Photo and video:
http://www.brashengines.com/FAQ.html
http://www.youtube.com/brashengines