Posted on 02/24/2013 9:18:11 AM PST by taildragger
Check out the video, the engine is small, model airplane size via the use of the propeller to give it a load, but it runs.
Wankels are notorious for lack of thermal efficiency, but to keep all the heat in and turn it into motion via ceramics could be a game changer.
Think about it;
* Omnivorous
* Smooth
* Small in size.
* It is uncooled, but is it unlubricated (?)
I see trucks hauling away loads of crushed vehicles every day, it’s not usually the engine that fails.
They were probably junked due to either automatic transmission failure, electrical problems or body rust.
A micro ceramic-Wankel might make a good small-engine power unit however, like a natural gas generator for your home, that runs 24/7.
I owned one (1972 version) for 3 days and then it went flying in Colorado when I was returning to Ft. Lewis Washington from Texas, they don't land very well, but the photo of it did make the front page of the local paper, it splayed, multiple end over end flips, multiple rolls, it did it all, it looked like it had gone through one of those crushers at the junk yard, but it sure was fast and responsive before that.
The problem with these, if memory serves, is low compression, i.e., they develop decent torque and in line with the drive train, but fuel economy (and therefore emissions) are lousy. The late Smokey Yunick was working on his self-described adiabatic, ceramic engine in the last years of his life, and his approach is probably better than this one. Regardless, the greater the difference between the engine and ambient temperature, the more work one will get out of the same fuel. Thanks taildragger.
I had a ‘93 twin turbo RX7 back in the 90’s. It was really lacking in low end torque, but once it started to get the rev’s up, man was it a blast. The power delivery was very similar to riding a high performance 4 cylinder sport bike. It cornered like it was on rails, and had very flickable precise steering. The closest thing to a true race car I’ve ever driven.
Add that to a this kid with the "Graphene" ultra-capacitor breakthrough, and you have a potential co-gen unit w/ storage and then if some low-cost solar comes along we are in game changer mode for sure...
“I had a Mazda rotary back in the 80’s. It was fun to drive but the engine blew up after about 50,000 miles of normal driving. Hope they got it right this time.”
Most new products have problems at first. Its amazing what 30 years of development and problem solving can do. The first cell phones were c**p also.
My father was a mechanical engineer, and I remember him hating the Wankel after they did some testing on them in his lab. They had nothing but problems with them once they got it under load and tried to make it do something besides just run.
I compare the Wankel to Betamax. Betamax was a great product, better than VHS, but the money and development went to VHS. The reciprocating piston engine has made remarkable advances in the last twenty years. Over 300 horsepower in six cylinder engines. Over 200 horsepower in four cylinder engines. Amazing. My old Musclecar had a huge eight cylinder engine to develop 350 horsepower. I think that fancy new Mustang is putting out around 650 horsepower from an eight cylinder engine. The Wankel has some great qualities. It’s just not getting the money and time.
I had a great ‘74 RX-4 wagon. Ran great until my sister drove it for a year without checking the radiator. I put a rotary short block in and drove it another 100K
http://alex62.typepad.com/imsablog/2006/02/mazda_rx7_winni.html
Mazda RX7 : winningest car ever
Bttt....
The diesel guys (funded by DoD/DARPA) have been working on ceramics for better efficiency for at least 25 years that I’m familiar with. So far, it hasn’t made the cost & reliability targets.
Wankel has great power density.
But deficient in efficiency (fuel econ) and emissions.
Those are what has kept it out of mass production cars.
They post on the video that it’ll burn any (liquid, I’m sure) fuel. But that begs the question of what sort of combustion/timing is going on - is it diesel, spark ignition, or glow plug (which might be difficult to avoid in an engine with no cooling system)? Carburated or fuel injected? What kind of compression ratio is involved, and is turbo supercharging possible (and/or necessary)?And what kind of seals/lubrication can withstand the temperatures involved???
Boy, I am not sure. I see a model airplane muffler and carb so is it burning the R/C type fuel which is what a methanol ? if my memory is correct. Perhaps this one was a glow plug I need to watch again closely....
In its fuel economy limitations and its high power density, the Wankel resembles a gas turbine. I was interested to learn recently about the Whittle gas turbine development. The Germans put the resources behind their jet aircraft program that the British mostly starved Whittle of. What was interesting, though, was that although the German axial flow design was very successful in the Me-262, and centrifugal jet engines have been unheard-of for many decades, Whittle fixed on the centrifugal principle early, and for a substantial reason - the need to withstand a high turbine inlet temperature, or TIT.Low TIT means low efficiency and low power, just as low compression ratio is an efficiency killer in a reciprocating engine. It makes sense that a centrifugal design would be better able to resist high TIT because the outside of the centrifugal turbine - at the turbine inlet - the stress on the turbine would be a minimum. The inner area of the turbine, exposed to lower temperature because the gas has expanded considerably in the outer part of the turbine, is where the material must withstand the centrifugal force exerted on the outer as well as the inner part of the whole disk.
In that sense Whittle had it right - the report I heard asserted that there is still extant a flyable British jet with a Whittle centrifugal engine built during WWII. Whereas the Germans, constrained as they were by materials availability, couldn’t build their axial flow turbines to fly for more than 30 hours before overhaul.
On two or three occasions, a seal between the transmission and engine failed which allowed ATF to leak into the combustion chamber. This produced enormous clouds of smoke, sufficient to keep down the mosquito population in our neighborhood. We found out that when the leak developed, we had exactly 30 miles of ATF burn capacity before the car wouldn’t move forward.
I’d heard of Whittle, but never in detail. Interesting reading his life story in the 1970s he wound up in the states as a prof at the Naval Academy.
Own an RX-8. Temperamental... yes. Mediocre gas mileage... yes. An absolute dream to drive... oh, H3LL YES!
I was so upset when they canceled the RX-line at Mazda. I can only hope they decide to make RX-9s by the time I’m looking for my next car...
The styling on a last generation RX is sort of love it or hate it, primarily due to the roofline and rear quarter glass, necessitated by that little secondary access door like extended cab pickups have.
Seems like a little mission creep, it’s always been a two seater with practicality being secondary, although I drove a first generation RX to south Florida and back from NC with four guys in it once over spring break, lol. Nice engine, turbine-like, a little weak off the line but man did it ever spin up, and smooth. To the downside, whrough a lot of oil, mileage was not great.
Resale is not all that good on the RX8 here for some reason. Are there any expensive mechanical bugaboos behind that? Seems like a desirable car otherwise.
My friend had a Mazda Wankel back in 1973. I don’t know the rpm that thing redlined at, but it turned FAST! One day we took it up to 117 mph.
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