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What if? Random Renesis/Rotary Thoughts

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Old 02-21-2006 | 06:41 PM
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What if? Random Renesis/Rotary Thoughts

What if the Front and Rear Rotors were reversed from each other? Instead of Both having itake and exhuast on one side of the block, have the Front on one side and the Rear on the other.

You wouldnt have a Siamesed center exhuast port then. Each Rotor could have it's own center exhuast port on its respective side of the center plate.

What if you made a 3 rotor this way. All side port like a Renesis Front rotor in/out on the Left, middle on the Right, rear on the Left. each end would have a dedicated center exhuast port. plus the Middle would have 2 exhaust ports on its side of the block one on the "forward" center plate and one one on the "aft" center plate.
Old 02-21-2006 | 06:45 PM
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I am having that Kenua Reeves feel right now....

Dude!

I understand the theory, but I am sitting here scratching my head trying to figure out how exactly that would work.
Old 02-21-2006 | 07:42 PM
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induction would happen down the centerline and split to either side like on a V- piston engine. exhuast could stay split as a true dual or the fore and aft could collect and then collect the middle
Old 02-21-2006 | 07:46 PM
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Keep talking...anything to entertain the 3-rotor idea is worth listening to.
Old 02-21-2006 | 08:09 PM
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It could be done. Two things about doing it this way. The first is that the intake/exhaust combination on the driver's side of the vehicle would be reversed. In other words the exhaust port would now be on top and the intake port on the bottom. This would make for some interesting plumbing. The second has to do with the combustion phases of the engine. 2 ways this could happen. The first is to leave the rotor phasing exactly as it is now with the rotors oriented 180 degrees off from each other. If you did this, you'd have both rotors firing at the exact same time as each other which is fewer pulses per revolution and a little less smooth running engine. The other alternative if you wanted to keep the same number of pulses per revolution, and alternating ones at that, would be to rephase the eccentric shaft so the rotors are each lined up next to each other. They may physically be in the same location of rotation in relation to the car but from a combustion standpoint they'd be 180 degrees apart which would bring us back to the same number of pulses we have now.

Another consideration is cooling through the engine. On the current setup we have alot of heat on the drivers, and bottom of the engine as compared to the much cooler top of the engine. The cooling jackets inside the engine take this into account. If we reversed one side, now we've got heat in more of the engine. All the way around. To make matters worse it's on the top half of one rotor and the bottom half of the other rotor. You'd have to be careful with aluminum housings so that they don't warp in relation to each other. It could be done though. You'd also have to consider that now you have an intake port directly adjacent to the hottest part of the other rotor.

Could it be done? Yes. Would it be worth it? Who knows.
Old 02-21-2006 | 08:36 PM
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actually Fred heat was one of the things om my mind. wouldn't it be "better" to spread the heat around more? a more even heat thru the whole engine could mean less worries about expansion and contraction of disparate materials. which could lead to longer seal life.

i had in mind runnign them 180 apart with the same number of pulses. not sure on the 3 rotor as i havent ever taken a look at the firing order on one.

why would the intake and exhaust swap places vertically?
Old 02-21-2006 | 08:47 PM
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What if the performance stayed the same but the car cost 20+% more because of all the complication? Low rpm performance might even drop because all that fancy intake tuning is probably out the window. Would you still buy one?
Old 02-21-2006 | 08:49 PM
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with your money?

someoen would have to design fancier intake plumbing tuning
Old 02-21-2006 | 09:38 PM
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emissions wouldnt be a problem - the exhaust is already hotter than a piston
Old 02-21-2006 | 10:50 PM
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Originally Posted by zoom44
with your money?

if that were the case you might be able to pickup a thirdhand Yugo in need of some TLC instead ...
Old 02-21-2006 | 11:15 PM
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Originally Posted by zoom44

why would the intake and exhaust swap places vertically?
Take an engine, or a picture of one, and rotate it 180 degrees over the eccentric shaft axis. Where is the intake port in relation to the exhaust port?
Old 02-21-2006 | 11:51 PM
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It would seem like a lot of plumping problems both internally and externally for a small benefit. As for cooling I believe the cooled water runs through the hot side of the engine then up to the cool side. Moving one hot side up top would create a number of coolant porting issues.

While we are theorizing, here is my pet idea. I find the current spark plug placement as having a number of flaws. Inefficient placement for ignition, gas seepage from one chamber to the next, fouling. The best placement would be to have the plug located on the face of the rotor were it could protrude into the center of the compression chamber. Of course this comes with a number of problems, weight of the plug on the rotor, no way to replace it, how to wire it. So I started to think rather then put a plug there would it be possible to create an arc from the rotor face to the housing at a specific location. This may be possible, you would have to insulate the spark emitter on the housing so that it would jump to the rotor face and not double back on the housing to complete the circuit. The rotor would have to act as ground and be close enough so the arc would find it as the path of least resistance. This set up would cause a far more effective spark but presents many problems but just might work.

What do you think.
Old 02-22-2006 | 12:02 AM
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it would also be sparking off the ring gear teeth, bearing/eccentric interface, rotor side housings, etc as it tried to make ground, not gonna work
Old 02-22-2006 | 12:02 AM
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The first rotary engine that Felix Wankel ever ran had 3 plugs. 1 on each rotor face. The idea was abandoned because of the reasons you listed.
Old 02-22-2006 | 12:05 AM
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I could have told him that I never read that or anything, just deduction
Old 02-22-2006 | 04:17 AM
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Mazda couldn't be bothered making different housing plus I think it might take a bit more space down under. Those are just my random thoughts though...
Old 02-22-2006 | 02:42 PM
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Originally Posted by rotarygod
Take an engine, or a picture of one, and rotate it 180 degrees over the eccentric shaft axis. Where is the intake port in relation to the exhaust port?
for the end plate? make em new with the holes cut in the right places. no rotating needed
Old 02-22-2006 | 03:10 PM
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You mean just have a runner that goes from the normal exhaust location to the other side of the plate, right?

It would probably make exhaust tuning more difficult, since the paths out of the engine would be different (by however long that runner is). I don't know much about exhaust tuning though, so maybe this would be beneficial?


edit:
For a 3 rotor, rotor 1 could have standard exhaust on the endcap. Rotor 2 could have smaller dual exhausts on the two housing plates running to the other side of the engine, and rotor 3 could have a standart exhaust on the other endcap.

Unless it would be bad for dual exhaust on that center rotor. I was thinking they would probably have to be a bit smaller than the ones on the end, so have two to make it flow the same.

As usual, I haven't got a clue what I'm talking about, so if my ideas are stupid just tell me :D

Last edited by Asmoran; 02-22-2006 at 03:15 PM.
Old 02-22-2006 | 03:27 PM
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Originally Posted by zoom44
for the end plate? make em new with the holes cut in the right places. no rotating needed
I know what you mean but the intake/exhaust ports that are located on the other side of the engine would be reversed. The exhaust port would be on top and the intake on the bottom. I merely said to flip if to show why this is so. If they weren't like this, you'd have to have counter rotating rotors.
Old 02-22-2006 | 04:14 PM
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damn its hard for me to visualze- i need a model but i think i see what you are saying
Old 02-22-2006 | 05:36 PM
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doh! i get it. yes the ports would have to be upside down compared to "normal"
Old 02-22-2006 | 06:45 PM
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Originally Posted by Ryan13b
Mazda has experimented with hundreds of different housing configurations. Between the FD and RX-8, was the rotary dark ages for Mazda, they had no official funding for research, but a few engineers still managed to keep making prototypes, using all sorts of different housing configurations.
Sorry I meant to manufacture and piece together different housings to make an engine, yes I know they tried different housings.
Old 02-23-2006 | 10:29 AM
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Originally Posted by Raptor75
It would seem like a lot of plumping problems both internally and externally for a small benefit. As for cooling I believe the cooled water runs through the hot side of the engine then up to the cool side. Moving one hot side up top would create a number of coolant porting issues.

While we are theorizing, here is my pet idea. I find the current spark plug placement as having a number of flaws. Inefficient placement for ignition, gas seepage from one chamber to the next, fouling. The best placement would be to have the plug located on the face of the rotor were it could protrude into the center of the compression chamber. Of course this comes with a number of problems, weight of the plug on the rotor, no way to replace it, how to wire it. So I started to think rather then put a plug there would it be possible to create an arc from the rotor face to the housing at a specific location. This may be possible, you would have to insulate the spark emitter on the housing so that it would jump to the rotor face and not double back on the housing to complete the circuit. The rotor would have to act as ground and be close enough so the arc would find it as the path of least resistance. This set up would cause a far more effective spark but presents many problems but just might work.

What do you think.
If that idea were possible wouldn't that also cause pitting in the housing from the arcing?
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