Ceramic Engines? 1

[Northboundtrain]

Hello,

I've been researching this subject and found some good information, but most of it is several years old. I've found claims that it is theoretically possible to build an engine using a ceramic material made of silicon for the block, pistons, head, etc. that is much more tolerant of heat (little or no cooling required), has much less thermal expansion, may require no lubricating oil (due to low friction coefficient), and weighs less than a metal equivalent. It all adds up to greatly increased power and fuel economy.

My question is whether fully ceramic engines are currently being developed and what, if any, success they have met with.

Also, how would the cost of a ceramic engine compare to that of a traditional metal alloy engine?

Thanks for any help

 

[GregLocock]

"My question is whether fully ceramic engines are currently being developed"

Probably

"and what, if any, success they have met with."

They succesfully get people to invest in them.

"Also, how would the cost of a ceramic engine compare to that of a traditional metal alloy engine?"

Well, given that cast iron costs about a thousand dollars a ton and the process for turning that into engines ha sbene around for almost 100 years, what do /you/ think the answer is?


Cheers

Greg Locock

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[patprimmer]

Presuming only internal combustion, and not electric, I would expect the relative costs are inversely proportional to the relative production numbers.

I would think that there are many 10s of millions, probably 100s of millions of metal engines made each year.

Say an average cost of say US$ 6,000 when you consider how cheap garden appliance engines are, but how expensive engines are for aircraft and ships.

There might be anywhere from none to 10 fully ceramic engines made per year

Call it 100,000,000 engines at US$ 6,000 vs 10 engines at X

X is a whole bunch of money.

OK OK, I guess it needs a correction factor, but it will still be a whole bunch.

Things that truly make significant fuel savings and have an environmental advantage, will get up if the cost penalty is moderate and there are no nasty side effects. So far I have seen no indications of it happening in this case.


Regards

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[Northboundtrain]

I guess the cost question is a hypothetical one. Very roughly, how would the cost of a production ceramic engine compare to that of a production metal alloy engine? Same price? Twice as expensive? Ten times as expesive?

Also, if anyone has a link to companies/groups currently experimenting with ceramic engines I'd appreciate it.

Thanks

 

[rmw]

I think I remember that Cummins did some work on ceramic engines a few years ago, but I have no way other than starting with "Google" to find out anything about it.

rmw

 

[patprimmer]

I think Honda also did some work with a ceramic Moto GP engine that had oval bores as well. Back in the 80's as I remember

Regards

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[franzh]

Several years ago (mid 80's I think) I saw a 4 cylinder diesel engine with ceramic cylinders and some poly composite rods and other engine parts. The name "Polymotor" rings a bell. It was operating in adiabatic state.
I seem to recall the head engineer stating that the cylinders were so hard they had to use diamond impregnated silicone blocks to etch the ceramic bores to mate with the rings. I also seem to recall that Smokey Yunick was involved. Hogwash until I saw it running in an engine lab. This was a time when I was hopping around engine labs, it was either in Florida or New Jersey; drat losing the gray cells, wish I could be a bit more selective about which ones went!
Franz

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[patdaly]

franzh,
I believe you are referring to Matty Holtzberg, the polymotor man. I have no idea where he is now.

 

[EHudson]

The Holtzberg polymotor engine was showcasing plastic components. Composite rods, plastic block that sort of thing. Amoco (Torlon) was a sponsor.

The adiabatic engines, like the Cummins metioned above were based on ceramic components. The target market was military applications as I recall. Tank engines and the like(?)

They were trying to achieve high thermal efficiency. It would seem that the ceramics of the day did not provide everything hoped for in engine components. Thermal shock may have limited the component life in these engines as it sometimes can in turbines.

 

[Azmio]

Northbound

There is an SAE paper about a research engine made out of ceramic. The research centered around the idea of having a fully adiabatic engine. It's a turbocharged engine and generating quite a good output considering that exhaust gas contains high entalphy value from the combustion heat that would otherwise be absorbed by the coolant. It's good for research purposes but I dont see how it can get into production at low cost.


Pat

If I'm not mistaken the Honda oval piston engine does not have ceramic block. Oval piston is problematic especially when thermal expansion of the piston comes into picture. Moreover, the piston ring wont be able to move around. With ceramic block, cant imagine how the expansions of different materials react with one and another.

 

[EngJW]

The Polymotor made it into a GTP race car in the 1980s. I saw it race at Watkins Glen and it finished around 10th.

 

[patprimmer]

Azmio.

I might be merging two different articles in my mind as the oval cylinder and ceramic experiments were in the same era and it was a long time ago.

I do appreciate the problems of producing oval rings and getting them to seal and the other precision engineering problems it involves. I think that is why I still recall some details after so many years.

Regards

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[franzh]

I remember the engineer now, but it was indeed top secret US Army data, actually trying to determine the longevity of an engine which may accumulate some battle damage. Operating in adiabatic state was a means of seeing if it would operate sans coolant, and ceramic was one of the only materials which would not self destruct or weld to other parts.
I sent the engineer a question, and yes, its still classified!
Franz

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[KyleWatson]

I remembered reading about carbon carbon quite a while ago, although its not the ceramic you are looking for, and it is very expensive to manufacture, but has the properties we were talking about. I looked up the first article about it that caught my eye, incase you're wondering. I'm sure most of you are more familiar with it than I am.

http://ipp.nasa.gov/innovation/Innovation54/complic.htm

 

[Azmio]

franzh

i read that particular SAE paper back in 98. It is written by a US Army researcher. Though much of other information remain classified, the paper revealed a lot of useful things already.

I forgot to point out one more thing, Heywood reported that during combustion, there will be lots of locally heated spots on the bore surface. this is bad for proper oil distribution on the bore surface.

 

[franzh]

Azimo:
I dont think we are talking about the asme engineer, but its possible. We worked together on a project about 15 years ago and he told me just enough to whet my appetite, but also qualified it with the top secret comment. He is no longer in the Army and is conducting engine research somewhere in the southeast US. I dont think it made its way to the SAE, would you have the engineers initials and/or SAE paper number?
Franz

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[Lissandre]

As silicon is abundant, the basic material cost is low.
Working the material is more expensive than working metal. Instead of melting and casting a process of pressurising powder, sintering and curing is used, which takes time.
After that, boring and finishing is easier and faster for the ceramic engine than for a metal one.
For the final finished product the ceramic engine has the advantage again as there are no radiator, fans, pipes and pumps to be installed.
The result?
An engine that is 25% cheaper to manufacture than a metal engine of the same size with 60% less power.
Note however that the price of the engine is only the minor part of a car price: an advanced engine like that of a BMW328 costs about $1500 ...
A batch of 10 ceramic engines of 1 liter (61 cubic inch), 400 kW (500 horses) capacity has been running a traffic simulation test program, including (German) highway driving at full speed for 10 hours.
The longest-running engine is now going for 20,000 hours without signs of wear and tear. This translates to about 2,000,000 km ( 1,200,000 miles) of average driving without servicing.


Try the following link:

http://www.geocities.com/CapeCanaveral/1614/

 

[Northboundtrain]

Yup, That's where I got a lot of my info. But I think that article is several years old. I don't know who the author is, but it sounds so optimistic that it leaves you wondering why someone isn't doing it already if it's that easy and cost-effective.

 

[GregLocock]

That price for a 328 sounds pretty cheap. Just about feasible, but only just.

Cheers

Greg Locock

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[Azmio]

Heywood reported that since heat is not transferred out of the adiabatic ceramic engine, the bore surface is likely to be heated up into many localized hot spots.

Since oil oxidation is likely to occur above 180 C, I wonder what will happen to the oil film thickness on the bore surface. I have a feeling that the oil consumption will be bad thus resulting to high HC emission as well.

Oh by the way, there are many other ceramic properties that may not react well with other engine components. I would worry a lot about its thermal expansion relative to TE of other materials.


Franzh

I read it a while ago and I dont have the author and the SAE paper number. You should be able to find it in the SAE website.

I have a strong feeling that the army researcher whom you met was the one that wrote that paper. If you succeed in contacting him again, tell him that I admire his research work.