Toroidal Engine Ready for Production

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."

Comments

Re:Timing

[FrostyWheaton]

But what happens if that timing belt goes?

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:Ok, I'm confused...

[Smidge204]

Ah.

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=

Useless because of technical hurdles

[Spamalamadingdong]

Rather than moderate, I decided to comment.

No they are not useless from a technical POW. One of the alternative designs should be used if we had to redesign all of engines, factories, fuels, motor oil and car's form factors.

Bull puckey. The choice of engine is at least somewhat independent of the choice of fuel; for instance, a spark-ignition piston engine will burn the same fuel as a spark-igniton Wankel, a diesel will burn anything that will ignite easily enough, and a Stirling or gas turbine can run on just about anything that burns, period. Fuels include:

• 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.

The design we use now is not the best one, it just happens to be the one whole automobile industry is shaped around.

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.