Ceramic Rotary Engine
#1
#5
mostly harmless
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Location: Greater Vancouver Area, BC
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it's true that when supply increases, price drops as cost per unit decreases (to a point) but there has to be demand enough to clear the market at a price where the company will still profit, right??
that's a "maybe someday" kind of idea... although ceramics are light, strong, and resistant to the effects of heat, they're also extremely brittle... i could see a rotor (but not the housings) being made largely out of ceramic components, and there are already heavy-duty racing ceramic seals (which happen to eat perhipheral housings for breakfast, but that's another story), but metals are still much cheaper (higher profit) and better suited to most applications in engines.
that's a "maybe someday" kind of idea... although ceramics are light, strong, and resistant to the effects of heat, they're also extremely brittle... i could see a rotor (but not the housings) being made largely out of ceramic components, and there are already heavy-duty racing ceramic seals (which happen to eat perhipheral housings for breakfast, but that's another story), but metals are still much cheaper (higher profit) and better suited to most applications in engines.
#6
Originally posted by Supercharger
This project is directed towards the consumer market, not F1.
Whenever a part is made in large quatity, costs come down.
This project is directed towards the consumer market, not F1.
Whenever a part is made in large quatity, costs come down.
The Mazda Hydrogen prototypes weren't production cars yet they had ceramic apex seals and a ceramic-metal coating on the insides of their rotaries.
It is widely known that economies of scale can bring costs down? Stating that does not change the fact that a mass production ceramic component will still be MUCH more expensive than a mass production iron or aluminum component.
#7
Ceramic materials' unique properties are attractive to engine designers. An alternative to a 100% ceramic engine is ceramic coated aluminum engine.
Please refer to "Engine Coating" thread for more information.
Please refer to "Engine Coating" thread for more information.
#8
Of course they are but this is not new information. If the costs were not so much higher, Mazda would have used them for their production rotaries. Refer to my previous posts from months ago hoping for such a thing.
The engine coating thread also does not have any new information for me to refer to?
The engine coating thread also does not have any new information for me to refer to?
#9
Like you have said so, ceramic apex seals offer all the beautiful properties of design & racing properties. But now, Mazda will not use this in production due to cost? Well, in a way it's sort of true, but many consumers don't see the cons of using ceramic apex seals. If 1 ceramic apex seal where to fail, it'll really get ugly since YOUR entire rotary engine just became a pile of garbage (you can ask the experts that have used them.) And, thus the liability cost of Mazda WARRANTY will be greater, cos now they have to replace you an entire engine.
I think IMHO that using carbon seals, will be better for performance & if they where to fail, damage will not be as much like the ceramic ones.
I think IMHO that using carbon seals, will be better for performance & if they where to fail, damage will not be as much like the ceramic ones.
#10
Extraordinary Engineering
I know that I'm reviving an old thread but I had to prove that I searched before posting this link.
http://ceramicrotaryengines.com/
Making An All-Ceramic Wankel Engine - Progress
The image opposite is a photo of a small Wankel Rotor we ordered to specification. It is made out of CeTZP (zirconia) ceramic. The ceramic manufacturer shaped the CeTZP rotor in the green (soft) state and was subsequently sintered (in a furnace).
The combustion chambers on the rotor faces and the slots at the apex where the tip seals are to be located have yet to be machined. It is likely that this will be done in the hardened state to ensure that tight tolerances will be met. The gear will be made out of steel and fitted into the central recesses. The low thermal conductivity of the CeTZP ceramic should ensure that the steel gearing is kept from overheating.
We are considering making the Wankel housing out of CeTZP ceramic as well. This should ensure that the heat generated during the combustion of fuel will be retained within the walls of the combustion chamber. A CeTZP ceramic Wankel engine should not require liquid cooling.
Adequate sealing at high temperatures is clearly a major issue. Lubrication using liquids is not possible at high temperatures (> 600 C). It is likely that solid lubricants have to be used. A soft metal (e.g. gold) coating on the inner surface of the ceramic housing with nickel-based apex seals, is one choice. Another choice is to invoke choke flow by introducing turbulence at the tips of the apex seals, but studies of this effect is limited and applying this effect could prove impracticable or the sealing could be inadequate.
and as a bonus
a silicon MEMS micro rotary engine - They want to produce ~30mW at 40,000 RPM
http://ceramicrotaryengines.com/
Making An All-Ceramic Wankel Engine - Progress
The image opposite is a photo of a small Wankel Rotor we ordered to specification. It is made out of CeTZP (zirconia) ceramic. The ceramic manufacturer shaped the CeTZP rotor in the green (soft) state and was subsequently sintered (in a furnace).
The combustion chambers on the rotor faces and the slots at the apex where the tip seals are to be located have yet to be machined. It is likely that this will be done in the hardened state to ensure that tight tolerances will be met. The gear will be made out of steel and fitted into the central recesses. The low thermal conductivity of the CeTZP ceramic should ensure that the steel gearing is kept from overheating.
We are considering making the Wankel housing out of CeTZP ceramic as well. This should ensure that the heat generated during the combustion of fuel will be retained within the walls of the combustion chamber. A CeTZP ceramic Wankel engine should not require liquid cooling.
Adequate sealing at high temperatures is clearly a major issue. Lubrication using liquids is not possible at high temperatures (> 600 C). It is likely that solid lubricants have to be used. A soft metal (e.g. gold) coating on the inner surface of the ceramic housing with nickel-based apex seals, is one choice. Another choice is to invoke choke flow by introducing turbulence at the tips of the apex seals, but studies of this effect is limited and applying this effect could prove impracticable or the sealing could be inadequate.
and as a bonus
a silicon MEMS micro rotary engine - They want to produce ~30mW at 40,000 RPM
Last edited by DarkBrew; 02-25-2007 at 05:18 PM.
#13
jersey fresh
Join Date: Dec 2005
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wow, novel idea. I have little experience in ceramic engineering, but some questions i'd have would be heat transfer and of course weight. Also durability compared to iron.
#14
We are considering making the Wankel housing out of CeTZP ceramic as well. This should ensure that the heat generated during the combustion of fuel will be retained within the walls of the combustion chamber. A CeTZP ceramic Wankel engine should not require liquid cooling.
#16
I don't buy Kool-Aid
#20
Sorry to practice my necromancy, but isn't heat loss through the large surface area combustion chamber one of the biggest problems with wankels? If you could create a housing and rotor that would minimize heat transfer and that could stand the heat, wouldn't it go a long way to help with this problem?
#21
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