efficiency of the rotary engine
09-08-2004, 11:39 AM
#26
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[QUOTE=shawnio
You realize you're riding around in a car with an extremely volitile fuel right now? They've dropped those thousands of psi hydrogen tanks from something like 20 stories without damage. You can bet those tanks are expensive. If you think riding around with gasoline is so much safer than hydrogen, you're not entirely correct. Either way, measures have to be taken to prevent the fuel from hurting people. I remember a certain recall recently on Ford Crown Victorias, they found that if they were hit from behind at a certain speed, there was a chance of the gas tank exploding.[/QUOTE]
Yes, I'm aware that gasoline is volatile. Any sort of fuel for combustion would, by definition, have to be.
From my experience with compressed gas bottles, if they were to use one of those for a gas tank on a H2 fueled car, the tank would be the heaviest part of the car. The most common type of those tanks are almost entirely solid steel, the ones that are used to hold 225 cu ft of air or N2 (uncompressed volume of gas there), have an internal volume of about 1.25 cu ft; with an outer diameter of about 9-10 in, they have a wall thickness of somewhere around 4 in, and they weigh in excess of 300 lb.
The other issue with LH2 is that unlike gasoline, exposure to just the liquid will cost you a limb (even without any sort of ignition source), and a ruptured tank leaking into a closed car cabin could (possibly) displace the oxygen out of the compartment relatively rapidly (although opening a window would prevent this sinc it'd fill from the top down) as the liquid boils off and expands.
I'm not saying it's not a worthwhile technology, or that we shouldn't be looking into it. It's just that designing/building the cars for it is only about 10% of the work that would need to be done (for the right price, they could probably have fuel cell cars in production within 2-3 years).
You realize you're riding around in a car with an extremely volitile fuel right now? They've dropped those thousands of psi hydrogen tanks from something like 20 stories without damage. You can bet those tanks are expensive. If you think riding around with gasoline is so much safer than hydrogen, you're not entirely correct. Either way, measures have to be taken to prevent the fuel from hurting people. I remember a certain recall recently on Ford Crown Victorias, they found that if they were hit from behind at a certain speed, there was a chance of the gas tank exploding.[/QUOTE]
Yes, I'm aware that gasoline is volatile. Any sort of fuel for combustion would, by definition, have to be.
From my experience with compressed gas bottles, if they were to use one of those for a gas tank on a H2 fueled car, the tank would be the heaviest part of the car. The most common type of those tanks are almost entirely solid steel, the ones that are used to hold 225 cu ft of air or N2 (uncompressed volume of gas there), have an internal volume of about 1.25 cu ft; with an outer diameter of about 9-10 in, they have a wall thickness of somewhere around 4 in, and they weigh in excess of 300 lb.
The other issue with LH2 is that unlike gasoline, exposure to just the liquid will cost you a limb (even without any sort of ignition source), and a ruptured tank leaking into a closed car cabin could (possibly) displace the oxygen out of the compartment relatively rapidly (although opening a window would prevent this sinc it'd fill from the top down) as the liquid boils off and expands.
I'm not saying it's not a worthwhile technology, or that we shouldn't be looking into it. It's just that designing/building the cars for it is only about 10% of the work that would need to be done (for the right price, they could probably have fuel cell cars in production within 2-3 years).
09-08-2004, 02:56 PM
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Originally Posted by bgreene
Yes, I'm aware that gasoline is volatile. Any sort of fuel for combustion would, by definition, have to be.
It's just that designing/building the cars for it is only about 10% of the work that would need to be done (for the right price, they could probably have fuel cell cars in production within 2-3 years).
It's just that designing/building the cars for it is only about 10% of the work that would need to be done (for the right price, they could probably have fuel cell cars in production within 2-3 years).
...i don't really know of any liquid that isn't volatile to some degree, i s'pose it's just a matter of how much.
anyhoo, biodeisel is awesome, and we don't need algae farms to produce all of it from new, recycle!! there are processes which can refine veyr high quality biodesiel (actually cleaner than your usual pump diesel) from cooking oil (which as it's 'food' would give you a pretty good reason why it'd be so clean in the first place).
i agree that the infrastructure swing will take a whole lot of work, but that'll be done mega, mega fast once big petrol isn't allowed to make refined gasoline for sale to the public; without some kind of now-unthinkable econmic or legal barriers to producing/consuming gasoline, there isn't much hope for an affordable alternative.
09-08-2004, 09:04 PM
#28
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Thermal Depolymerization is cool, but there probably isn't enough trash and whatnot for it to power all of civilization for any length of time. However, it might be the key to making the vast quantities of oil shale (in Canada and elsewhere) economically viable.
09-09-2004, 09:16 PM
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Shawnio wrote: Regenerative braking will likely never be used on a sports car. Talk to cortc about unsprung rotating weight and think about how heavy these motors/generators are. They are usually mounted on each wheel similar to rotors and calipers. It would be neat, if they could attach something elsewhere, maybe a driveshaft, or in the transmission. Perhaps something that worked like engine braking from the transmission, you lightly use the brakes while pushing in the clutch, a clutch to the generator is engaged and it slows down the wheels. Of course, this generator would charge a lightweight capacitor, which would discharge when you need to accelerate again.
09-22-2004, 03:53 PM
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Interesting link with energy content per volume of various fuels:
http://www.osti.gov/fcvt/deer2002/eberhardt.pdf
http://www.osti.gov/fcvt/deer2002/eberhardt.pdf
09-24-2004, 04:24 PM
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Just imagine this: fill in your tank with distilled water. Turn on the ignition, battery fires up a high-voltage discharge coil, electrolysis happens, H is separated from O and you are ready to drive around. Now, the only trick is to figure out 3 things:
1. The separation system must be self contained and self sufficient, meaning that, the energy required to initiate the separation should come from the vehicle itself (there is plenty of energy being wasted by cars today....I am sure they can figure out a way to turn it back into electricity. Heck! alternators!)
2. Figure out a safe, reliable process to home-made Hydrogen production. (this may not be so easy!)
3. Make such device fit in a compact sized car.
The idea of using H as a fuel is a beauty. Its regenerative: byproduct of 'combustion' is water, which goes back into the atmosphere, creates clouds, it rains, and gets back to wells, etc.
Sorry, but I gotta go back and keep working on my PocketH device. I'll get back with ya'll once I figure all out. Let's say in...NEVER!
1. The separation system must be self contained and self sufficient, meaning that, the energy required to initiate the separation should come from the vehicle itself (there is plenty of energy being wasted by cars today....I am sure they can figure out a way to turn it back into electricity. Heck! alternators!)
2. Figure out a safe, reliable process to home-made Hydrogen production. (this may not be so easy!)
3. Make such device fit in a compact sized car.
The idea of using H as a fuel is a beauty. Its regenerative: byproduct of 'combustion' is water, which goes back into the atmosphere, creates clouds, it rains, and gets back to wells, etc.
Sorry, but I gotta go back and keep working on my PocketH device. I'll get back with ya'll once I figure all out. Let's say in...NEVER!
09-24-2004, 05:17 PM
#32
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Thermodymanics might have a thing or two to say about any system that takes in low temperature water, and without any external energy input is able to produce output of high temperature water vapor AND has energy left over to do work (like moving a car around).
Short of annihilation of mass into energy (some sort of fission/fusion type reaction), you shouldn't even be able to use the H2/O2 engine to run a generator capable of powering sufficient electrolysis to fuel itself. Such a device would fall under the category of "perpetual motion machines", and if we could actually produce one of those, fuel of any sort would likely become a non-issue....
[Edit by author] My bad, I guess I should have read all the way to the last line before responding.
Short of annihilation of mass into energy (some sort of fission/fusion type reaction), you shouldn't even be able to use the H2/O2 engine to run a generator capable of powering sufficient electrolysis to fuel itself. Such a device would fall under the category of "perpetual motion machines", and if we could actually produce one of those, fuel of any sort would likely become a non-issue....
[Edit by author] My bad, I guess I should have read all the way to the last line before responding.
09-24-2004, 08:51 PM
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Originally Posted by RX8-TX
Just imagine this: fill in your tank with distilled water. Turn on the ignition, battery fires up a high-voltage discharge coil, electrolysis happens, H is separated from O and you are ready to drive around.
09-24-2004, 09:09 PM
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Originally Posted by robertdot
That was pretty much what I envision for the future (some time). But some people just want to use bio diesel...
09-28-2004, 05:51 PM
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Actually the future might be in fuel cells that run on methanol. Methanol has a much higher energy content per volume than hydrogen. And methanol can still be produced with plants and therefore wouldn't produce any net greenhouse gases.
Oh, and Indy cars have been running on methanol for 40 years now.
And here's your pocket fuel cell:
dpreview.com/news/0406/04062401toshibafuel.asp
Oh well, ultimately there are many ways to get rid of the dependency on oil without having to sacrifice anything in the long run.
Oh, and Indy cars have been running on methanol for 40 years now.
And here's your pocket fuel cell:
dpreview.com/news/0406/04062401toshibafuel.asp
Oh well, ultimately there are many ways to get rid of the dependency on oil without having to sacrifice anything in the long run.
09-28-2004, 07:40 PM
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Here's another link on methanol fuel cells. Clicky. Interesting technology, and even if it's only expected to top out at 40% efficiency that's still fairly close to the efficiency of modern internal combustion engines.
09-29-2004, 07:53 AM
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Unless you're looking at high efficiency internal combustion engines installed in ships like this Sulzer engine: http://www.bath.ac.uk/~ccsshb/12cyl/
I doubt that you'll find a car engine that reaches 40% efficiency.
(Whoa, talking about low end torque...)
I doubt that you'll find a car engine that reaches 40% efficiency.
(Whoa, talking about low end torque...)
09-30-2004, 12:28 AM
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The best line from that site PoorCollegeKid posted was this.
"Therefore, some companies have embarked on developing a Direct Ethanol Fuel Cell (DEFC)."
Does that mean in the future, machines could run off beer? That's hilarious ... just like in Futurama.
Just going back to my first post ...
"Look to the way they increase efficiency in piston engines. Lightweight parts, check. Dynamic intake manifold, check. Variable "valve" timing, check ... opening and closing changes with rpm, although rotaries don't have valves. Throttleless intake, nope. Combustion swirl, dunno about this. Direct injection, nope."
Any throttleless intake idea I can think of is preposterous. Combustion swirl is beyond me, and it seems Direct injection would require mapping the path of air through the chamber as it's pushed around by the rotor. I don't think anyone has published any information like this, and so ... any more ideas?
"Therefore, some companies have embarked on developing a Direct Ethanol Fuel Cell (DEFC)."
Does that mean in the future, machines could run off beer? That's hilarious ... just like in Futurama.
Just going back to my first post ...
"Look to the way they increase efficiency in piston engines. Lightweight parts, check. Dynamic intake manifold, check. Variable "valve" timing, check ... opening and closing changes with rpm, although rotaries don't have valves. Throttleless intake, nope. Combustion swirl, dunno about this. Direct injection, nope."
Any throttleless intake idea I can think of is preposterous. Combustion swirl is beyond me, and it seems Direct injection would require mapping the path of air through the chamber as it's pushed around by the rotor. I don't think anyone has published any information like this, and so ... any more ideas?
09-30-2004, 08:11 AM
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Actually I guess we'd be all surprised how much has been published, invented and even sold. I guess since the world is run by financial people and not engineers many rational concepts don't make it and completly irrational concepts have a huge success (for instance, look at SUV's).
Some info regarding swirling of air (the concept is actually much older then most people might think):
1934 Saurer, a Swiss truck manufacturer made a Diesel engine and was using valves with blades to swirl the air around the vertical axis. The fuel was injected into a cavity in the piston and then swirled around the horizontal axis which significantly improved the combustion process. At the same time the manufacturer was testing Diesel engines with 4 valves per cylinder. (Saurer went bankrupt in the 80's - for financial reasons.)
Some info regarding swirling of air (the concept is actually much older then most people might think):
1934 Saurer, a Swiss truck manufacturer made a Diesel engine and was using valves with blades to swirl the air around the vertical axis. The fuel was injected into a cavity in the piston and then swirled around the horizontal axis which significantly improved the combustion process. At the same time the manufacturer was testing Diesel engines with 4 valves per cylinder. (Saurer went bankrupt in the 80's - for financial reasons.)
Last edited by globi; 09-30-2004 at 11:59 AM.
10-01-2004, 12:05 PM
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Originally Posted by RX8-TX
Just imagine this: fill in your tank with distilled water.
Still big big technical hurtles before Hydrogen is an option
10-01-2004, 05:26 PM
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Magic8 wrote: Big problem with this is that water freezes in the winter and vaporizes in the summer. May be no problem with the tank but how about the hoses, fittings and the fuel cells themselves.
10-01-2004, 06:36 PM
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Actually, algae can be used to create hydrogen.
If you take regular algae and starve it's sulfur supply, the algae produces hydrogen as a byproduct, when the algae is done producing and is at the end of it's own life cycle (typically as long as 8 days) you introduce some sulfur into the water the algae is in and it will replenish itself, and you can do this over and over again. I think algae farms are going to start popping up, pools of the stuff set on daily cycles. This would be a good cost effective way of mass producing hydrogen. No need for biodiesel which is still emits slight polution.
If you take regular algae and starve it's sulfur supply, the algae produces hydrogen as a byproduct, when the algae is done producing and is at the end of it's own life cycle (typically as long as 8 days) you introduce some sulfur into the water the algae is in and it will replenish itself, and you can do this over and over again. I think algae farms are going to start popping up, pools of the stuff set on daily cycles. This would be a good cost effective way of mass producing hydrogen. No need for biodiesel which is still emits slight polution.
10-04-2004, 10:45 AM
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Technical issues aside, noone has solved the most important issue - Business. Somebody hasn't come up with a good business model that allows a company to be profitable by researching and implementing hydrogen power anything.
Don't forget that before cars, kerosone (product from oil) was used almost exclusively to light lamps. So some of the distribution infrastructure was already there. If cars didn't come around, the oil industry would have died when the light bulb and electric dynamos were invented.
Don't forget that before cars, kerosone (product from oil) was used almost exclusively to light lamps. So some of the distribution infrastructure was already there. If cars didn't come around, the oil industry would have died when the light bulb and electric dynamos were invented.
03-02-2005, 05:13 PM
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Ok here's a solution to make a rotary engine more efficient. (Significantly more efficient than a gasoline piston engine.) Just use the 2 stage rotary engine concept that Rolls Royce used with its rotary Diesel engine:
http://www.der-wankelmotor.de/Motore...lls-royce.html
You make an engine with 2 rotors similar to the current design of most of the rotary engines. The first rotor however has displacement of 1.5l (2.3 times the width of the current rotors) and the second rotor has a displacement of 0.65l.
The 1st rotor feeds the 2nd rotor with fresh air and the 2nd rotor feeds the 1st rotor with exhaust gases again. (Exaktly like the Rolls Royce engine but just with the 2 rotors in line instead of on top of each other.)
The second rotor does the actual ignition and the first rotor does part of the compression and expansion work. The second rotor has a low compression ratio of 7 and therefore improves the shape of the combustion chamber (volume to surface ratio) and allows a better combustion process. (The fuel would be injected after the first stage.) The total compression ratio would then be 16 (1.5/0.65*7), which should tremendously improve the fuel efficiency of the engine.
The engine should be able to deal with that total compression ratio as long as the intake charge is well cooled after the first rotor.
If you look at the Evo it has a compression ratio of 8.8 at a boost of 19 psi with pump gas, which actually leads to a higher total compression ratio than this 2 stage rotary engine. Why not use a turbo in the first place? Because the turbo does only work at high throttle settings. A 2 stage rotary engine would work at any throttle setting, since the larger rotor would do expansion work at low throttle setting too. Besides a rotary engine stage might have a higher adiabatic efficiency than a centrifugal compressor (turbo), since the compression stage is sealed. (But of course requires somewhat more space and mass).
To reduce the pressure loss from small rotor to large rotor, the rotors would be connected with peripheral ports (just at this point).
Advantages of this concept:
* Higher total compression ratio = higher efficiency
* Lower compression ratio of 2nd rotor = better combustion
* Only 2 spark plugs required
* Only one intake and one exhaust required
* Lower flammability limit since the ignition only happens in one rotor
* Since the larger rotor is exposed to lower temperatures it could be built out of Aluminium and the engine should therefore not necessarily be heavier.
* The larger rotor allows the exhaust gases to further expand before the reach the exhaust port opens and therefore mufflers don't have to dampen as much anymore.
* It's an all mechanical solution. No direct injection or anything fancy would be required.
Disadvantages of this concept:
* The motor would require more space.
* The motor would run rougher since it would still be the smaller rotor that generates most of the power.
I wonder why this hasn't been considered? Since this concept wouldn't really be feasible with a piston engine since the valves would probably generate to much air restriction to make it worth while.
http://www.der-wankelmotor.de/Motore...lls-royce.html
You make an engine with 2 rotors similar to the current design of most of the rotary engines. The first rotor however has displacement of 1.5l (2.3 times the width of the current rotors) and the second rotor has a displacement of 0.65l.
The 1st rotor feeds the 2nd rotor with fresh air and the 2nd rotor feeds the 1st rotor with exhaust gases again. (Exaktly like the Rolls Royce engine but just with the 2 rotors in line instead of on top of each other.)
The second rotor does the actual ignition and the first rotor does part of the compression and expansion work. The second rotor has a low compression ratio of 7 and therefore improves the shape of the combustion chamber (volume to surface ratio) and allows a better combustion process. (The fuel would be injected after the first stage.) The total compression ratio would then be 16 (1.5/0.65*7), which should tremendously improve the fuel efficiency of the engine.
The engine should be able to deal with that total compression ratio as long as the intake charge is well cooled after the first rotor.
If you look at the Evo it has a compression ratio of 8.8 at a boost of 19 psi with pump gas, which actually leads to a higher total compression ratio than this 2 stage rotary engine. Why not use a turbo in the first place? Because the turbo does only work at high throttle settings. A 2 stage rotary engine would work at any throttle setting, since the larger rotor would do expansion work at low throttle setting too. Besides a rotary engine stage might have a higher adiabatic efficiency than a centrifugal compressor (turbo), since the compression stage is sealed. (But of course requires somewhat more space and mass).
To reduce the pressure loss from small rotor to large rotor, the rotors would be connected with peripheral ports (just at this point).
Advantages of this concept:
* Higher total compression ratio = higher efficiency
* Lower compression ratio of 2nd rotor = better combustion
* Only 2 spark plugs required
* Only one intake and one exhaust required
* Lower flammability limit since the ignition only happens in one rotor
* Since the larger rotor is exposed to lower temperatures it could be built out of Aluminium and the engine should therefore not necessarily be heavier.
* The larger rotor allows the exhaust gases to further expand before the reach the exhaust port opens and therefore mufflers don't have to dampen as much anymore.
* It's an all mechanical solution. No direct injection or anything fancy would be required.
Disadvantages of this concept:
* The motor would require more space.
* The motor would run rougher since it would still be the smaller rotor that generates most of the power.
I wonder why this hasn't been considered? Since this concept wouldn't really be feasible with a piston engine since the valves would probably generate to much air restriction to make it worth while.
03-02-2005, 05:43 PM
#45
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I've got 4 pages on this subject from a book I have called "The Wankel Rotary Engine: A History". Here are the first 2 pages. I'm still scanning the others. Hopefully you can read these good enough.
03-02-2005, 05:45 PM
#46
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Originally Posted by globi
Ok here's a solution to make a rotary engine more efficient. (Significantly more efficient than a gasoline piston engine.) Just use the 2 stage rotary engine concept that Rolls Royce used with its rotary Diesel engine:
http://www.der-wankelmotor.de/Motore...lls-royce.html
You make an engine with 2 rotors similar to the current design of most of the rotary engines. The first rotor however has displacement of 1.5l (2.3 times the width of the current rotors) and the second rotor has a displacement of 0.65l.
The 1st rotor feeds the 2nd rotor with fresh air and the 2nd rotor feeds the 1st rotor with exhaust gases again. (Exaktly like the Rolls Royce engine but just with the 2 rotors in line instead of on top of each other.)
The second rotor does the actual ignition and the first rotor does part of the compression and expansion work. The second rotor has a low compression ratio of 7 and therefore improves the shape of the combustion chamber (volume to surface ratio) and allows a better combustion process. (The fuel would be injected after the first stage.) The total compression ratio would then be 16 (1.5/0.65*7), which should tremendously improve the fuel efficiency of the engine.
The engine should be able to deal with that total compression ratio as long as the intake charge is well cooled after the first rotor.
If you look at the Evo it has a compression ratio of 8.8 at a boost of 19 psi with pump gas, which actually leads to a higher total compression ratio than this 2 stage rotary engine. Why not use a turbo in the first place? Because the turbo does only work at high throttle settings. A 2 stage rotary engine would work at any throttle setting, since the larger rotor would do expansion work at low throttle setting too. Besides a rotary engine stage might have a higher adiabatic efficiency than a centrifugal compressor (turbo), since the compression stage is sealed. (But of course requires somewhat more space and mass).
To reduce the pressure loss from small rotor to large rotor, the rotors would be connected with peripheral ports (just at this point).
Advantages of this concept:
* Higher total compression ratio = higher efficiency
* Lower compression ratio of 2nd rotor = better combustion
* Only 2 spark plugs required
* Only one intake and one exhaust required
* Lower flammability limit since the ignition only happens in one rotor
* Since the larger rotor is exposed to lower temperatures it could be built out of Aluminium and the engine should therefore not necessarily be heavier.
* The larger rotor allows the exhaust gases to further expand before the reach the exhaust port opens and therefore mufflers don't have to dampen as much anymore.
* It's an all mechanical solution. No direct injection or anything fancy would be required.
Disadvantages of this concept:
* The motor would require more space.
* The motor would run rougher since it would still be the smaller rotor that generates most of the power.
I wonder why this hasn't been considered? Since this concept wouldn't really be feasible with a piston engine since the valves would probably generate to much air restriction to make it worth while.
http://www.der-wankelmotor.de/Motore...lls-royce.html
You make an engine with 2 rotors similar to the current design of most of the rotary engines. The first rotor however has displacement of 1.5l (2.3 times the width of the current rotors) and the second rotor has a displacement of 0.65l.
The 1st rotor feeds the 2nd rotor with fresh air and the 2nd rotor feeds the 1st rotor with exhaust gases again. (Exaktly like the Rolls Royce engine but just with the 2 rotors in line instead of on top of each other.)
The second rotor does the actual ignition and the first rotor does part of the compression and expansion work. The second rotor has a low compression ratio of 7 and therefore improves the shape of the combustion chamber (volume to surface ratio) and allows a better combustion process. (The fuel would be injected after the first stage.) The total compression ratio would then be 16 (1.5/0.65*7), which should tremendously improve the fuel efficiency of the engine.
The engine should be able to deal with that total compression ratio as long as the intake charge is well cooled after the first rotor.
If you look at the Evo it has a compression ratio of 8.8 at a boost of 19 psi with pump gas, which actually leads to a higher total compression ratio than this 2 stage rotary engine. Why not use a turbo in the first place? Because the turbo does only work at high throttle settings. A 2 stage rotary engine would work at any throttle setting, since the larger rotor would do expansion work at low throttle setting too. Besides a rotary engine stage might have a higher adiabatic efficiency than a centrifugal compressor (turbo), since the compression stage is sealed. (But of course requires somewhat more space and mass).
To reduce the pressure loss from small rotor to large rotor, the rotors would be connected with peripheral ports (just at this point).
Advantages of this concept:
* Higher total compression ratio = higher efficiency
* Lower compression ratio of 2nd rotor = better combustion
* Only 2 spark plugs required
* Only one intake and one exhaust required
* Lower flammability limit since the ignition only happens in one rotor
* Since the larger rotor is exposed to lower temperatures it could be built out of Aluminium and the engine should therefore not necessarily be heavier.
* The larger rotor allows the exhaust gases to further expand before the reach the exhaust port opens and therefore mufflers don't have to dampen as much anymore.
* It's an all mechanical solution. No direct injection or anything fancy would be required.
Disadvantages of this concept:
* The motor would require more space.
* The motor would run rougher since it would still be the smaller rotor that generates most of the power.
I wonder why this hasn't been considered? Since this concept wouldn't really be feasible with a piston engine since the valves would probably generate to much air restriction to make it worth while.
03-02-2005, 06:09 PM
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Thanks RG, I'm curious about this. What's also interesting is that Rolls Royce is apparently working on a gasturbine with a rotary engine, which is supposed to have a higher efficiency than the current gas turbines.
The rotary engine does obviously a part of the compression and expansion work which is usually done by axial compressors and axial turbines. Apparently the rotary engine must do this more efficiently otherwise they wouldn't have patented this 1997. This would also mean that a staged rotary engine is more efficient than a turbo charged rotary engine even at full throttle settings.
The rotary engine does obviously a part of the compression and expansion work which is usually done by axial compressors and axial turbines. Apparently the rotary engine must do this more efficiently otherwise they wouldn't have patented this 1997. This would also mean that a staged rotary engine is more efficient than a turbo charged rotary engine even at full throttle settings.
03-02-2005, 06:26 PM
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Originally Posted by Ajax
Isnt this what wankel intended his original rotary for? To boost a piston engine?
What Rolls Royce did is different (the compressor is connected to the e-shaft and still sort of driven by the exhaust gases).
I don't see a reason why this concept wouldn't work on a gasoline rotary engine as longs as you use it with an effective intercooler.