Bet that got yalls attention:)
I just read about the new carbon fiber nanotube wheels and got to thinking----damn brain will not let me alone.
Would it be cool if we had a rotor made from this(if possible -?thermodynamics etc)---just think of what would happen if we could lose 4lbs(guess) off one rotor?
Holy batman!
olddragger

Carbon fiber and carbon nanotubes are different things. While principally the same, carbon fibers are 5,000 times larger than carbon nanotubes, which are still in their infancy as a technology. Also, carbon nanotubes have incredible tensile strength but any force perpendicular to the nanotube will have no trouble bending it.

But yes, halving the weight of a rotor would be fantastic. Has anyone tried titanium yet?

yes.. it will bend... but you can have the nano tubes "interweave" to something that looks like a hand knitted yarn potholder. saw a kick ass demonstration at bnl one time

halving the weight of the rotors would allow us to increase the redline to around 12-13k RPM... (whether or not we want to is another question)

anyone actually know something about materials tech? would love to see some discussion to this effect...

just think of the lessen load on the bearings, the quick reving, the ability to run LARGER rotors!! Boogles my mind.
OD

But yes, halving the weight of a rotor would be fantastic. Has anyone tried titanium yet?

Not sure. A few years ago visiting a Kennametal plant I saw some very interesting triangular parts they sintered from Titanium, and they looked almost exactly like rotors that needed some final machining. A little larger than the 13B rotors. They wouldn't comment on the customer or application.

halving the weight of the rotors would allow us to increase the redline to around 12-13k RPM... (whether or not we want to is another question)

anyone actually know something about materials tech? would love to see some discussion to this effect...

air flow....

hence not sure if we would want that.. give it another set of ports and probably another stage in the VFAD.. :lol:

i would lean towards believing anyone who discussed doing the possibility of something this extreme would also understand and be fine with the fact the OEM intake manifolds are gonna have to go

Not sure. A few years ago visiting a Kennametal plant I saw some very interesting triangular parts they sintered from Titanium, and they looked almost exactly like rotors that needed some final machining. A little larger than the 13B rotors. They wouldn't comment on the customer or application.

Are any aspects of titanium technically insufficient for this application? It IS a bit ductile, especially at temp. Could there be a creeping problem?

Bet that got yalls attention:)
I just read about the new carbon fiber nanotube wheels and got to thinking----damn brain will not let me alone.
Would it be cool if we had a rotor made from this(if possible -?thermodynamics etc)---just think of what would happen if we could lose 4lbs(guess) off one rotor?
Holy batman!
olddragger

Then we would need a new set of S/C impellers.....
Clutch?
The transmission would need to go away.
Differential?
RX8 sub-frame?

i'd be more enthusiastic about a ceramic rotary engine... at least it would catch on fire and burn

halving the weight of the rotors would allow us to increase the redline to around 12-13k RPM... (whether or not we want to is another question)

anyone actually know something about materials tech? would love to see some discussion to this effect...

The only real problem with that is the transmission will fall apart at such high revolutions. The Renesis was benchmarked and pushed all the way up to 15,000 RPMs with no problems by the Mazda engineers. The only problem was that when they attached a transmission to it, the transmission fails.

...sooooo....a better transmission...?

omg idk wtf im talking about...why am i so mechtarded?

why am in this thread?

why am i even posting?

The only real problem with that is the transmission will fall apart at such high revolutions. The Renesis was benchmarked and pushed all the way up to 15,000 RPMs with no problems by the Mazda engineers. The only problem was that when they attached a transmission to it, the transmission fails.

The 5 speed by mazsport could help with that. If an F1 engine can rev to 20K than a 10-15k tranny can't be unfeasible.

I'm more concerned with the actual material of the rotors. I think that the point of titanium is that it is as strong as steel with half the thickness. That means to lighten a rotor while keeping the strength, one would have to design a rotor that is hollow in some areas to lose any real weight.

If this proves to be a feasible option than I may move on this. Just need to get information first.

Well, if you have that kind of time/money, you may as well buy a few grams of carbon nano-tubes to mix into your Ti-Al alloy and get another 50% strength increase with zero mass increase.

I'd like to see an F1 team get its hands on some rotary engines and see what they could do with em, with their crazy resources...

I'd like to see an F1 team get its hands on some rotary engines and see what they could do with em, with their crazy resources...

+1:Eyecrazy:

yea baby--i can see and hear in my little mind a rx8 coming down the front straight at 15K---whoa baby---think people would want one then?
olddragger

carbon nanotubes will never be used in a rotor, sorry guys, it takes so long for one to "grow" about a millimeter let along a rotor lol, plus there extremely expensive to buy (for research or any other projects). also so far they have only been able to grow them in straight fibers.

sorry im a physics nerd and at boston college they have a huge research team devouted to carbon nanotube technology so "carbon fiber nanotube rotary" was kinda unsettling :lol:

"carbon nanotubes will never be used in a rotor"

Ahh, a member of the "establishment." I'll kindly ignore your comments as similar comments are usually proven absurd approximately 20 years after they're made.

"never" is just way too long to be taken seriously any how. Is it a viable production concept? Not right now. Making an entire rotor out of them would be less than ideal, too. But doping alloys with nano-tubes is proving VERY beneficial in the strength to weight ratio department.

the earth is flat. careful not to fall off...

hate to break it to ya but they are already making wheels from this stuff
must be able to grow them ok!
olddragger

Olddragger, are you sure they're carbon nanotubes and not just regular old carbon fiber? I doubt nanotubes are being used in any consumer application, let alone wheels. They'd cost about $200k each. Carbon fiber wheels hit the market recently and they're very light but expensive and fragile. I hear they're prone to shattering in bad potholes. After all, carbon fiber is just fiberglass with a different layup material.

What I would like to see, as mentioned, are rotors made of a lighter metal like titanium or aluminum or some alloy. I'm sure these have already been tried and deemed unsuitable for one reason or another (my guess is thermal expansion or cost).

Really, though, I think they should give this a go: http://en.wikipedia.org/wiki/Amorphous_metal

I know one thing. nothing is for certain. god i love supercomputers. material science gets better and better... why ... the server.. yes the server.. no longer do you need a few million... now a dell server rack is only 15k. thank you tech:)

Olddragger, are you sure they're carbon nanotubes and not just regular old carbon fiber? I doubt nanotubes are being used in any consumer application, let alone wheels. They'd cost about $200k each. Carbon fiber wheels hit the market recently and they're very light but expensive and fragile. I hear they're prone to shattering in bad potholes. After all, carbon fiber is just fiberglass with a different layup material.

What I would like to see, as mentioned, are rotors made of a lighter metal like titanium or aluminum or some alloy. I'm sure these have already been tried and deemed unsuitable for one reason or another (my guess is thermal expansion or cost).

Really, though, I think they should give this a go: http://en.wikipedia.org/wiki/Amorphous_metal

Nanotubes have been used in golf shafts for a couple of years now...

Nanotubes have been used in golf shafts for a couple of years now...

nanotubes, or just carbon shafts? There's a big difference. I've used carbon-shaft arrows for years now but they're not nanotubes.

Edit: wikipedia says nanotubes have been used in mountain bike handlebars, but they're "bulk" nanotubes, kind of a mass of broken-up nanotubes held together with substrate. And they're just reinforcing conventional polymer, not forming the structure in its entirety. I don't think plastic, even with nanotubes in it, are gonna work inside a rotary.

carbon golf club shafts
carbon fiber wheels
bulk carbon nano-tubes as a stiffening additive in a number of applications, including polymers and alloys.

Unfortunately, carbon-nano-tubes (there are nano-tubes of other elements as well) increase thermal conductivity, which in an IC engine application would prove a detriment to BSFC. I don't think the rotary needs that.

Of course, a thermally reflective ceramic coating on a Ti-Al (cnt doped) rotor and housings would be really cool. ;)

I think you'd be better off using ceramics for the rotor housing and the seals, and superalloys for everything else. If you've ever seen some of the ceramics they have now, they're insane. They use them(and superalloys) in jet turbine engines to minimize creep, and their strength doesn't decline with heat until the last 10% or so before its melting point. If everything moving in that engine were ceramic or superalloy, I wouldn't be surprised to see 20k+ rpms coming out of that. Gear that down enough and you have a serious monster of an engine..

by the time nano technology is developed enough to make it practical to use such materials in an engine, we wont be driving internal combustion rotary engines

carbon fiber has been around since the 60's and only recently its appearing in consumer parts, soooo

so from what I can see. we all need flux capacitors?

P.S. they should make rotors out of diamonds.

Are any aspects of titanium technically insufficient for this application? It IS a bit ductile, especially at temp. Could there be a creeping problem?

Titanium, while ludicrously light, is far too brittle. There is a reason they don't make car wheels out of titanium. And it's not just because each wheel would cost $5,000 bucks.

^ although an alloy might work...

Diamond coated super titanium alloy mega super duper rotor!! yippeee. Now in the for sale section :).

so from what I can see. we all need flux capacitors?

P.S. they should make rotors out of diamonds.

Diamond coated super titanium alloy mega super duper rotor!! yippeee. Now in the for sale section :).

I'd actually like to see the interior surface of the rotor and side housings, as well as the seals made from either vapor deposition synthesized diamond or laminates of vapor deposition synthesized diamond and flame sprayed sapphire. The coefficient of friction of diamond on diamond is equal to wet ice on wet ice while having a melting point around 5000F. If the seals and coating were sturdy enough, we might be able to do away with oil injection, further cleaning up the exhaust and allowing more latitude on air/fuel mixtures while still meeting emission targets.

As far as the rotors themselves, I'd like to see them made boron carbide/aluminum composite. The material was originally developed as potential armor for helicopters where weight is a critical issue; but conventional ceramic armor lacks second strike protection. The aluminum gives the ceramic a modicum of toughness that it would not otherwise achieve.

and yall though i was kidding around---ha!
OD

And to think, I nearly made an on topic reply to this old thread...