third_shift|studios

here's a question...can you get more power if you had a twin-rotary engine? Consider it would be set up like a DOHC, only with 2 rotary chambers side by side. Then externally, chain driving a flywheel. Would it work? Would it be powerful or have too much parasetic loss from the chain drive?



I'm sure my proportions are off

staticlag

? twin rotary? As in 2 rotors? or as in 4 rotors total?

Ahriman4891

I think it's cool. As I understand, one of the main problems of the Wankel engine is the stress on the e-shaft as you increase the number of rotors. In this design, you have 2 shorter shafts. If Mazda ever decides to build an 6/8-rotor Veyron killer this would help.

GODFATHER

it would snap a timing chain and if you want to do that it would be easier just to put in a 4 rotor

third_shift|studios

how would 4 be set up? I"m not used to this rotary stuff, i'm a v8 guy =) just kinda started thinking about a dual rotary system

staticlag

2 13Bs with a special eccentric shaft connecting them = 4 rotors, 2.6 Liters of displacement

GODFATHER

like he said two rx8 or rx7 motors slapped together.... kind of difficult to do unless you have your own machine shop

magikone69

not too sure if it would be a good idea, a properly setup 3 rotor can already make more then enough power. plus i guessing a twin 2 rotor engine (4 rotors) will have super shitty gas mileage. and will be uber difficult to fit in any engine bay. i think mazda jus needs to keep workin on the 2 rotor and try to make it more mainstream as far as reliabily/power/mileage goes...and perhaps work on getting back in the turbo rotary game...even if its just a small amount of boost.

Soravia

It's called 4 Rotor set up. Basically normaly rotary engine with one rotor added at each end of the engine and the shaft changed so it moves with 4 rotors instead of two. Not very hard to figure out at all. Just the materials are not easily out in the market opposed to piston engines.
And yes, the gas milage is very poor, that's why it's only found in Mazda racing cars.

Using a chain like the OP idea would be impossible to get any decent power. A single misfire in one engine would kill the thing. Replacing the chain with a shaft would be better idea.

kersh4w

iTrader: (3)

i think the problem would be is that the engine would be too wide. but it might work. and i dont see how a misfire would kill the engine, as its not the eccentric driveshaft that would output, you would get slack when the 2 shafts lined up horizontally. unless the tensioner moved around like that of a bicycle.

however, this idea has merit because it makes the engine almost as short as a 2 rotor. keeps the weight farther back. but. uh. i think it would be too wide. also, you might have to mount the double engines too high up, and that would make the car top heavy.

DMRH

Nice of you to put in the thought & animation but the practical aspects of your idea fails unfortunately.

To manufacture a rotary engine as you suggest would invoke losses leading it to be impractical for street use.

Two rotors inline is far more efficient than two rotors side by side. Or four rotors inline being more efficient than two X two rotor engines side by side.

REgards

Flashwing

Even if you were able to produce such a design as having two rotary motors working together, the primary benifit of the rotary engine is it's small size vs. power output.

With this design, you would end up increasing the needed space to the extent you would need a ton of realestate to do what a 4 rotor rotary could easily accomplish.

Interesting concept...

nycgps

iTrader: (1)

Its not possible. Enough said.

daisuke

the germans tried this out in WWII with piston engines, they made a 2 prop bomber with 4 engines, it failed because the engines tended to overheat and then catch fire.

VW makes some engines like this on some of it's current cars, the W12 in the phaeton and toureg come to mind, same as the W16 in the veyron. so it works in piston engined designs. I'm not sure how they tie them together, but I'm sure it's more complicated and safer than with a chain.

I think it could work, with the flywheel in front of the engines instead of below them so that a belt or torque box from each engine would power the shaft that spun the flywheel. Yes the engine would be wide and unlikely to fit in a normal car, but what kind of normal car needs the power given by such a monstrous engine or can fit it? answer: the veyron

the bugatti veyron will run at 250 mph for only 12 minutes before running out of a full tank of gas. Over that time it will travel 50 miles and get all of 1.9 mpg.

so the idea would probably work, but an inline 4 rotor like the 26B would be more space efficient. I do wonder if they could actually ever make a 4 rotor based on the renesis tho because of it's side porting system.

now TWO 26B's side by side coupled up like that... that's what I'M talking about :D

KpaBap

You could get one of these pups



It's diesel even...

Viich

WTF is that? The two rotors aren't even the same size!

KpaBap

The top rotor is used as a supercharger for the bottom one:

skrubol

iTrader: (1)

The VW 'W' engines (W8, W12, W16, must be a multiple of 4,) still only use one crank shaft. The Cylinders are just arranged in 4 rows rather than the 2 of a V or the 1 of an inline. There's a bit more to it than that, but it's really just a glorified V design.
The closest thing this would be to is an H configuration iirc. This configuration consists of 2 horizontally opposed engines, each with its own crank, either geared or chained together. I don't think there have been any production engines of this type. Actually, after consulting Wikipedia, it appears a U configuration has also been tried, which is the same as the H except using inlines instead of horizontally opposed.
http://en.wikipedia.org/wiki/U_engine

fmzambon

That was the Daimler Benz DB 606, a pair of DB 601 joined together.

Check here for a few data and a photo (look at the last entry in the "variants" section).

A few more info in the link about the Heinkel He-177, the airplane that was supposed to use the engine.

They also tried it again with two DB 605 engines, creating a DB 610 (link, always last entry in the "Production versions" section; photo on the right)

Jedi54

iTrader: (7)

another advantage of the Rotary is it's ability to be mounted low and far back in the engine bay. If you place them side by side, it wouldn't fit in anything close to an 8 or an RX7.
Nice idea though, but 4 rotors lined up would make more sense.

Also, 4 rotors = SUPER expensive and only put in race cars. 3 rotors however....

PhillipM

Of course what you'd really do would be build a pair of 4-rotor engines, and then link those side by side....

Razz1

Interesting ideas.........

daisuke

read the print, the lower (bigger) rotor is the supercharger for the smaller one!

how much do 26Bs go for? I know 20Bs sell for something like $15,000 iirc.

DOMINION

I recall a few years back at Seven Stock, Someone had a Blue Rotary powered car that had a Rotary Engine in the front and one in the back. That was working. Anyone?

mattison71

The rotors are different sized because one is just a supercharger, the bottom (bigger) one is the engine.