Ozimandious

Not just the apex seals but the whole engine!!! run it as hot as you want. Now imagine what you could do with this engine...

http://ceramicrotaryengines.com/

thoughts?

Chad D.

iTrader: (19)

I wonder what kind of exhaust you would need and if it would need extra shielding.
I say this because most of the heat would get deflected out.
It would probably take a while to get up to temps.
I'm skeptical.

Vlaze

iTrader: (14)

https://www.rx8club.com/series-i-tech-garage-22/ceramic-rotary-engine-2384/

Ozimandious

Awesome concept... just think what you could do with it... run it at a higher compression... cleaner and more power and much less cooling needed. Wonder how well you could balance the whole thing for higher revs?
Either way bloody interesting to me anyways. THOUGHTS????
http://ceramicrotaryengines.com/

zoom44

updated as of this month? what did they do, finally fix some of the spelling errrors? i dont really see anything different.

Shinka_MJR

umm... anyone catch this:

"A high torque engine, rotary engines also run more smoothly."

seriously?

tjbourgoyne

The pics on their site are strange, one guy looks like he's working in his garage. The other two looks like nightlife in 1972.

deadphoenix52

wow an update. that site has been around since like 2004. and its shown up here many times. i checked in periodically for about a year but it seemed the project was dead. theres a big thread on it buried here somewhere

Joe-the_tattoo_artist

I noticed a repetition of an erroneous statement that metals are a good conductor of heat. Metals are in fact poor conductors of heat.

This story does remind me of Fords GT90 which used ceramic shielding in the engine bay to help cope with its copious amount of heat. Ceramics being an excellent conductor of heat.

Vlaze

iTrader: (14)

I think you're confused between the meaning of what a thermal conductor and insulator are. There's a reason thermal conductivity of metals are high and ceramics are low in any material properties specifications.

Arca_ex

iTrader: (10)

You have it backwards. Metals are good conductors of heat and ceramics are poor conductors of heat.

Put a piece of wood and a piece of steel out in the sun for awhile. Now touch both of them. The metal FEELS hotter correct? They're actually both the same exact temperature but the metal is much more efficient at transferring that heat to your skin.

The reason you use ceramic heat shielding is because it is a poor conductor of heat and prevents the transfer of heat from one side of it to the other.

reddozen

iTrader: (1)

It's only about 1" around. I've talked to them before. I like their idea, but not their method. If I'm not mistaken, they've also joined up with a couple other ceramic rotary groups. The problem is that they're using a specialized variant of ceTZP, and that limits their production size to 1"x3" if I remember correctly.

Like I said, good idea, but not my choice of approach. Standard ceTZP isn't super expensive, but there are still manufacturing concerns with ceramics.

They are nice guys though.

MBTwenty

Shinka, I almost tried to kill the bug on your signature. Thought it was on my screen.

alnielsen

iTrader: (4)

Two separate threads with the same title were merged.

deadphoenix52

Joe-the_tattoo_artist

Thermal conductivity of "good" or "poor" is determined by how rapidly a material absorbs and/or dissipates heat. "Good" meaning that it does so relatively quickly and "poor" meaning that it does so relatively slowly.

Joe-the_tattoo_artist

Had the writer used the terms "high thermal conductivity" and "low thermal conductivity",it would have made more sense.... but, he did not.

kma5783

iTrader: (7)

This is exactly why metals are good conductors of heat they absorb and dissipate heat pretty rapidly, now ceramics on the other hand absorb and dissipate heat very slowly making them bad conductors. Good job at disproving your own previous statement

Joe-the_tattoo_artist

Not true... The effect of temperature on thermal conductivity is different for metals and nonmetals. In metals conductivity is primarily due to lattice vibrations and free electrons, however, free electrons play a dominant role. Therefore any increase in temperature increases the lattice vibrations but affects the movement of free electrons adversly thereby decreasing the conductivity. On the other hand conductivity in nonmetals is only due to lattice vibrations which increases with increasing temperature, and so the conductivity of nonmetals increases with increasing temperature.

Using the wood vs metal example that was used previously... the rate of change in temperature is greater for the wood than the metal; making the wood a better conductor of heat. In other words, which one "conducts" heat more rapidly?

kma5783

iTrader: (7)

First off congrats on quoting a Wikipedia article and obviously understanding these concepts in an incorrect sense.

Think about what you're saying and realize you're wrong. Why do we make radiators out of metal? Hint: They conduct heat very well. Why do we use ceramic coating on exhaust headers? Hint: The ceramic doesn't conduct heat very well, therefore keeping the heat in the header where it belongs.

And now your trying to say wood conducts heat better than metal? Are you really that stupid?

Joe-the_tattoo_artist

There was no misunderstanding on my part.

The radiator is a good conductor of heat not because of the material but, because of its large surface area. The radiator fluid itself is an even better conductor of heat because it absorbs and dissipates heat very rapidly compared to the engine block materials.

Ceramic coated headers are good conductors of heat (compared to their non-coated counterparts) because the ceramics absorb and dissipates heat more efficiently than the metal that it coats.

Joe-the_tattoo_artist

Just to make things a bit more specific, I am not referring to the thermal conductivity within a single material... yes, I agree, metals have a higher thermal conductivity than non-metals. I am referring to how rapidly heat transfers from a given material to another.

kma5783

iTrader: (7)

Ok you can believe that, but stop misleading other people.

I have a question for you then, There's three radiators one made of metal, one wood, and one ceramic. The surface area is the same on all of them which one performs better and why?

Now as far as ceramic coating an exhaust header do understand why people do it? Ceramic coating will reduce underhood temps and also the surface temp of the header. Why does it do this? Because it keeps the heat contained in the header and sends out the exhaust or through a turbo. A ceramic coated header results in higher EGT's which in Turbo applications results in higher efficiency and faster spool times. Now think about why exhaust gas temps would increase by coating the header. If you were correct EGT's would go down because more heat would be dissipated by the header and underhood temps would also increase, seems like a pretty dump thing to do doesn't it.

I would suggest you do some more research cause you're wrong in everything you've said so far.

Joe-the_tattoo_artist

It was not my intention to start a debate on the definitions of certain principles of thermodynamics. I was merely making an observation that the writer of the article had used less than accurate terms.

kma5783

iTrader: (7)

Well your first post in the thread included the statement that "Metals are in fact poor conductors of heat" which is definitively false, so I'm not sure where you were going with this?