Toroidal Engine Ready for Production 57
FarceMajeur writes "Business 2.0 has a column on a recently prototyped "round engine," properly named a toroidal engine, by VGT Technologies, Inc. Nice Flash animations of the concept are here. I've always admired the Wankel engine, but it seemed more like a time bomb than a going concern. This engine is billed as the 'world's first practical Concentric Positive Displacement Engine,' meaning no eccentric rotation to generate vibration, meaning fewer catostophic failures, one would hope."
rotary engine? (Score:1, Interesting)
Re:rotary engine? (Score:1)
The older Mazda RX-7 had a turbo version that was fast as hell, but overpriced and heavier than it needed to be.
The ne
Re:rotary engine? (Score:1)
Re:rotary engine? (Score:2)
It's a Good Thing!(tm)
RE5 (Score:1)
Re:rotary engine? (Score:2)
It said the Wankel was inherently vibration prone. I tried to figure out why that would be. The Wankel piston is like a triangular spirograph. Its edges sweep out a figure eight shaped cavity. I could see how the mass of the piston sweeping out first one lobe of the figure eight, and then the other, would cause the engine to vibrate.
This engine has the pistons rotate arou
Canadian Gov't Automotive Genius.::rotary engine? (Score:1)
It's supposed to vibrate less than a Wankel. That's why the power-take-off from the toroidal rotor is through hammering on this two-bladed offset wedge. Hey, there's another winning idea.
Still, it's a definite leap forward in one regard: it's better than the $27 million in genetic engineering the Otta
The article doesn't really make it clear (Score:3, Informative)
Anyway, it's an interesting piece of technology.
Yet another revolutionary internal combustion eng (Score:4, Interesting)
Reciprocating pistons and poppet valves still live because they work well, can be manufactured with simple operations and have seals (piston rings and valve seats) that will last for years.
I thought about a design like this many years ago and concluded that there would be major difficulties sealing in the combustion gases. I guess time will tell whether the problem has been solved.
Re:Yet another revolutionary internal combustion e (Score:2)
"Useless for one reason or another" (Score:2, Interesting)
Useless because of technical hurdles (Score:5, Informative)
- light and medium petroleum distillates;
- petroleum byproducts such as propane;
- methane (fossil or biogenic);
- vegetable oils and derivatives such as biodiesel;
- heavy petroleum fractions;
- wood, wood gas and charcoal;
- coal.
For any one of those fuels, I can cite an example of one of the above families of engines running on it. If an engine isn't being widely used, it's because it's difficult to manufacture or requires expensive materials. Right now we are using the least-expensive (and thus most cost-efficient) technology we've got, and that's the right thing to do. In a word, hogwash. There are a host of different engine designs around, and some of them have even achieved some presence in the marketplace. Examples:- Wankels
- Stirlings
- Gas turbines
We don't use the Wankel because it has too much chamber surface area per unit displacement, causing heat losses to be greater than a piston engine and losing the efficiency race. We don't use Stirlings because they are external-combustion engines requiring very high temperatures to be efficient, and the materials for the hot-side heat exchangers are not cheap. We don't use gas turbines because they require (again) heat exchangers to be most efficient, and (for vehicles) nobody's come up with a design which isn't either too bulky or loses too much efficiency to leakage; for road vehicles, turbines remain the province of superchargers, not the main power producers.A lot of research money has been expended on these engines in the past. Superior technologies do win out, just as fuel injection has displaced carburetors from all US production cars. If you can come up with a way to beat the technical problems which prevent any one of these engines from being manufactured as cheaply as a piston engine while meeting the same efficiency, emissions, noise etc. requirements, the world will beat a path to your door.
What is wrong with turbines? (Score:2)
I am not trying to challenge you. I'd really like to know. Why does the M1 Abrams tank use a turbine? And if there is a good reason for it doing so, why doesn't the M2 Bradley AIFV? I know they use
Re:What is wrong with turbines? (Score:2)
The first search result [g2mil.com] is pretty interesting.
/mike
I liked your point... however (Score:1)
There are only about two major reasons why Rotary (or Orbital) engines are not in wider use (I used to work for a lab that worked on them). First the pins wear out causing gas leakage... we couldn't solve that one... not that the existing pins are not reliable... but they wear out, and repairs are *very* expensive. Secondly most leak oil, though ours didn't any more than a normal engine... and I am told that the new Mazda one's don't suffer that either.
Re:Useless because of technical hurdles (Score:2)
For example our current ICE's are very intolerant about bad fuel while the others designs you cite aren't. Most of gasoline isn't directly separated petrolium, but produced from it by not-so-inexpensive processes. However since we already invested billions of R&D to produce gasoline efficiently and trillions on refineries, it can be produced relatively cheaply
Re:Yet another revolutionary internal combustion e (Score:2)
An additional problem is the law of conservation of energy or Newton's third law. It'll be interesting to see how his "patentable" design keeps the pistons rotating within a common torus.
A Representative Sample (link) (Score:1)
Not revolutionary, actually a throwback (Score:2)
Not a throwback (Score:3, Informative)
Nope. Read the white paper. It describes the compression and expansion clearly. Here's the process:
Re:Not a throwback (Score:2)
Funny, I thought I had. I must've been misled by the utter lack of coverage of the pertinent issues in the animations.
I count that as a disadvantage. The separate combustion chamber means
Ok, I'm confused... (Score:3, Interesting)
Re:Ok, I'm confused... (Score:3, Interesting)
Now here's an interesting thought. You have two (hopefully dynamicaly balanced) flywheels (aka "Gyroscopes") with their axes perpendicular to eachother... very similar to the gyroscope arrangement in a navigational gimbal - used to make a platform that is rotationally stable to provide a reference point for measuring the rotation of your craft.
What would happen if you m
Re:Ok, I'm confused... (Score:3, Interesting)
And, as I said, this was also despite friction, which would also be a necessary thing to worry about given that the flywheel is mounted somewhere
Re:Ok, I'm confused... (Score:2, Insightful)
Re:Ok, I'm confused... (Score:4, Informative)
No, the second wheel is not being hit by the main wheel. That would be bad. The taper on the "wings" is to provide an offset. (The wings act as valves - blocking off ports in the top and bottom of the engine body.)
The "vertical" wheel is driven by a gear and belt system from the "horizontal" wheel. I would've thought all the threads about timing belts/chains would have tipped it off, if you somehow managed to not notice the huge belt and pulley assembly on the sife of the engine in those 3D models.
There doesn't have to be a flywheel. The inertial mass of the components provides that function.
=Smidge=
Yeah, but the physics isn't intuitive (Score:3, Interesting)
A navigational gyro table uses three gyroscopes as sensors; the actual rotation of the table to keep it fixed in space is done with motors, not torque from the gyros. If you applied any torque to the gyros, they would precess and wouldn't be pointing in the same direction any longer.
The total gyroscopic moment of the
Re:Yeah, but the physics isn't intuitive (Score:2)
The problem that was experienced in WWI was one of cooling. Cooling was not a problem while the aeroplane was flying, when there was substantial airflow over the engine to provide cooling. Rather, when the aeroplane was taxiing or sitting still the engine of a conventional radial engine was subject to overheating as there was but little airflow over the engine, thus as radials ar
Timing (Score:4, Interesting)
What would happen if a timing belt gave out on a 'normal' cylinder-based engine? I'm not too knowledgable about engines, but it doesn't seem like it would be quite as catastrophic.
Re:Timing (Score:4, Informative)
that does seem to be a huge problem with this engine's design. it may be a timing chain (less prone to failure) on these engines though.
rotary is the best engine design when it comes to failures, but is also not very efficient and seems to have been dropped by everyone (basically mazda).
Re:Timing (Score:1)
Re:Timing (Score:3, Informative)
Not always. As a mechanic by trade, I can offer the following...
It actually comes down to how they designed the engine. Generally, an overhead valve engine is either free-running, or it is not. If it is free running, then the pistons can rise to top dead center without contacting any valve which is fully open. This is, as already stated, by design. In this case, a cam belt breakage will still leave you stranded, but the cost of repair will be limite
Re:Timing (Score:1)
Moving off-topic, what proportion of modern engines are free-running?
Re:Timing (Score:2)
The beauty of modern internal-combustion engines is that they aren't quite as dangerous in a failure as the old big-blocks they use to make in the 30s.
Re:Timing (Score:1)
Re:Timing (Score:4, Informative)
Re:Timing (Score:2)
Re:Timing (Score:1, Informative)
Re:Timing (Score:5, Informative)
It depends....
The timing belt/chain keeps the valves opening and closing in sync with the turning of the crankshaft. If that belt fails the valves will cease to move.
In some (most?) enginges the valves do not travel past the highest point of travel of the piston at any time. In this case, all that will happen is the engine will cease working and need to have the timing belt/chain replaces.
However if there is no clearance between the top of the piston's travel and the bottom of the valves travel (as in come higher performance engines) you will have catastrophic failure of some sort as the pistons collide with the valves. Repairs for this type of failure will be huge.
To return to the topic: Failure of the timing belt in this engine would be very nasty. The rotating "piston" would collide directly with the auxilliary wheel most likely fusing the two together if not ejecting the smaller wheel from the engine. Either way, it would be niether pretty or repairable.
Re:Timing (Score:2)
Re:Timing (Score:2)
Re:Timing (Score:1)
Not quite [google.com]. The timing belt turns the camshaft which opens and closes the valves. All modern engines have camshafts and timing belts (or timing chains), with two exceptions: 2-stroke engines (motorcycles, snowmobiles, etc) and Wankels (Mazda RX-7, etc).
I'm taking the don'ts (Score:5, Interesting)
IANAE, but this is likely to be a crackpot/scam venture.
The phrasing I've quoted above, which come from the web site, are big red flags. They're trying to pitch Pekau instead of the engine. Along the lines of "he's really smart and knows what he's doing, so of course his engine works." This is how scam after scam after scam gets pitched. "Ignore all the nay-sayers, because they just don't understand what our guy has done."
The phrase "which is well-documented" is also a tip off. Nobody says that unless it's not quite true.
Wise move (Score:1)
Re:I'm taking the don'ts (Score:4, Insightful)
They have a prototype, but only one picture of it.
They have a video of the prototype in some sort of testing facility, but the sound is intermittent, the video cuts from scene to scene for no apparent reason, and there isn't ever a shot OF THE ENGINE actually running. Think "alien autopsy" but not as credible.
Tell you what, guys. If you've got a WORKING PROTOTYPE of a revolutionary (no pun intended) internal combustion engine, and if you've already applied for the patents, then why not spend an hour producing a decent video of your invention in action?
As they say, extra-ordinary claims require extra-ordinary proof.
--
Nutating Spherical Engine (Score:1)
This reminds me of a nutating (wobbling, essentially) sphere engine I read about at McMaster Motor [mcmastermotor.com].
I have a little more faith in McMaster's credentials, and the design seems more realistic.
Re:Nutating Spherical Engine (Score:2)
If we get hydrogen as fuel source I'm all for sticking in a normal engine.
This wobble looks cool, but I don't see how it's going to work.
nice theory, and real world snake oil (Score:2, Interesting)
the wankel worked, btw. it just didn't turn out to be much more efficient because the piston-crank method is so refined. it was more of a marketing disaster because mazda made them a little too cheaply after a big PR campaign. they had to remove it from their sedan line but could keep in their sports car because those
The main problem... (Score:4, Interesting)
Those tight fit parts that absolutely fly by each other have to meet, slide, and keep a pretty good seal. Each time the timing chain is a little off, say to increase or decrease in power, they will miss a little, bonk, and get worn. Hot exhaust gasses slipping through will probably cause preignition in the little transfer tube. Nasty.
Also notice how much physical distance the compression arms of the rotor have to move each cycle. Can you imagine the heat from friction and the lubrication required? And the kinds of seals that you would need? I guess you could get decent lubrication by using the rotor as some sort of centrifugal oil pump, but still the wear would be nasty.
Consider as well that it's basically a 2 cylinder 4-stroke engine. It's gotta be a pretty good size and run at a pretty high RPM to get enough power to be really useful.
Don't count on this one.
Re:The main problem... (Score:1)
This thing, however, faces the problem of keeping a unidirectional slider lubricated and sealing on the power rotor, and on the valve rotor, adds to that the problem of a continuously made-broken seal, where the gap goes by.
One thing they don't seem to men
Hydrogen is not an option (Score:2)
...the problem with hydrogen is that overall, it is not the slightest bit cleaner. It's cleaner to BURN, but to make it, the current popular proposal is to make it from, guess what, petroleum or natural gas. You just lost, best case, half the argument for alternative energy- ALTERNATIVE :-) Worst case, you're creating just as much pollution because, say, it turns out the cheapest/easiest way to make hydrogen involves all sorts of
"concept" page is flat-out wrong (Score:2)
A reciprocating piston engine generates maximum combustion chamber pressure when the angle of the crankshaft is least effective.
That's -sort of- correct, but the diagram is VERY misleading; it's implied that compression = the explosion. and worse, that the instant you start the explosion, you get all your power, which is simply not true.
In a reciprocating piston engine, combustion is far from instantaneous. It's called the flame front speed, and it varies with compr