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Australian Team Working On Engines Without Piston Rings

Unknown Lamer posted about 7 months ago | from the more-power dept.

Transportation 368

JabrTheHut writes "An Australian team is seeking funding for bringing an interesting idea to market: cylinder engines without piston rings. The idea is to use small grooves that create a pressure wave that acts as a seal for the piston, eliminating the piston ring and the associated friction. Engines would then run cooler, could be more energy efficient, and might even burn fuel more efficiently, at least according to the article. Mind you, they haven't even built a working prototype yet. If it works I'd love to fit this into an older car."

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368 comments

It won't work (-1, Troll)

Anonymous Coward | about 7 months ago | (#45883261)

Trust me, I have a PhD in engineering.

Re:It won't work (0, Troll)

Anonymous Coward | about 7 months ago | (#45883321)

Agreed. No chance this is feasible.

The piston would need to have a coefficent of thermal expansion which was in keeping of that of the bore liners. If not massive friction forces or blow-by/lack of compression would ensue as the engine warmed up.

However, if the above could be controlled the piston material would need also need to have a very low coeeficient of friction to render the use of rings obsolete.

On the whole it is, at present, an unfeasible idea.

Re:It won't work (4, Funny)

Cryacin (657549) | about 7 months ago | (#45883527)

So... in other words, you're saying that the whole thing is blowing a bunch of hot air?

How about Ceramic Engines ? (5, Interesting)

Taco Cowboy (5327) | about 7 months ago | (#45883991)

From the TFA:

"... that an absolute seal isnâ(TM)t that important, and eliminating the friction generated by the rings on the cylinder wall can have far-reaching effects on engine design on the whole "

" ... that the whole thing is blowing a bunch of hot air?"

If they _ CAN _ use that bunch of hot air to form a seal, and achieve a drastic reduce of friction in between the piston ring and the bore itself, I feel that it's time for the return of the ceramic engine.

The chief reason why ceramic engine doesn't make it into the mainstream despite having had under research since the 1970's is that the friction in between the piston ring and the wall of the bore itself result in the wearoff of the ceramic material in the form of a pile up of fine ceramic dust inside the chamber.

If what the vendor said is proven to be true, then we should bring the ceramic engine back to the fore-front.

Re:It won't work (2)

sunderland56 (621843) | about 7 months ago | (#45883667)

This also removes the piston-to-liner pathway as a way of cooling the piston head - the hardest part of an internal combustion engine to keep cool.

Re:It won't work (3, Informative)

LWATCDR (28044) | about 7 months ago | (#45883931)

That has been solved for a while. Oil jet to to bottom of the piston. They have been doing that for a long time in racing and motorcycle engines.

Re:It won't work (4, Insightful)

muphin (842524) | about 7 months ago | (#45883687)

How the ringless piston works:
In place of the rings, each piston has numerous small, angled grooves, semi-circular at their apex. With the small clearances between them, the movement of the piston creates high-speed eddies -- air pressure working like metal rings to cut leakage and loss during the compression and combustion strokes.

“That means there’s no metal-to metal contact between the pistons or rotors and their mating cylinders or housings. Virtually no friction means the mechanism needs no lubrication and there’s no wear and tear on major components,” said Trigg.

There’s an important by-product here, too. Putting an “air cushion” around the periphery of the combustion chamber creates a stratified air-fuel charge – an injection profile that enriches the mixture in the centre of the chamber and leans it up towards the periphery.

TDC/BDC (0)

Anonymous Coward | about 7 months ago | (#45883803)

What about when the piston is motionless or slow?

Re:TDC/BDC (0)

Anonymous Coward | about 7 months ago | (#45883911)

It's gonna knock like a motherfucker....

Re:It won't work (2)

LWATCDR (28044) | about 7 months ago | (#45883941)

So will this mean that sleeve valves will be practical.

Re:It won't work - sure about that? (1, Interesting)

ridgecritter (934252) | about 7 months ago | (#45883745)

I wouldn't dismiss this right away.

If the physical features on the piston provide resistance to gas flow along the piston/cylinder annulus similar to that provided by piston rings, they wouldn't need a close-fitting piston - therefore no expansion coefficient headaches. It may also be that the hydrodynamics tend to center the piston in the cylinder, which would reduce contact events and scuffing wear.

You could probably get a feasibility go/no check with a few weeks' worth of modeling. The resonance interactions in the piston grooves when the combustion pressure front reaches them would be very interesting to see.

Re:It won't work (5, Insightful)

cold fjord (826450) | about 7 months ago | (#45883333)

Trust me, I have a PhD in engineering.

Would you care to expand upon that? Or is this the scenario we are looking at below?

If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong. -- Arthur C. Clarke [brainyquote.com]

Or perhaps we simply have a loose troll?

Re:It won't work (5, Interesting)

Anonymous Coward | about 7 months ago | (#45883833)

Trust me, I have a PhD in engineering.

Would you care to expand upon that? Or is this the scenario we are looking at below?

I'm an engineer too, but without PhD. I don't know what he was thinking of (or even if he is an engineer at all), but I can say one major flaw that I noticed. The piston rings serves two functions and they only consider one.

The article deals with combustion, which is on top of the piston. It never mentions what is below, which is the piston rod and the crankshaft. The connection between those two needs to be well lubed, but the construction makes it really tricky to lube a "run away" bearing. The solution is to make an "oil fog", which sticks to everything, including the cylinder below the piston. When the piston moves downwards, the piston rings scrape off the oil from the cylinder and provides a clean surface for the combustion.

When running an engine with cracked piston rings, lube oil will start to enter the combustion. This will produce toxic black and foul smelling exhaust and the engine "will be burning oil". Even worse the oil burns badly and leaves behind soot, which will damage/block the valves. Some of it will stick to the cylinder wall and not be removed by the piston rings, which mean it ends up in the lube oil. The higher the amount of soot in the oil, the worse lubing ability it has. Eventually you have an engine with enough oil, but no lubing.

In short: no piston rings will destroy every valve and bearing in the entire engine and replacing it could be cheaper than repairing it.

I consider this to be a far more serious problem than anything the article mentions and I find it rather shady that they completely avoid this rather serious issue. It isn't like it is an unknown problem. If you run big engines like trains or ships, then you will periodically test the oil for soot (and other stuff related to other defects) to detect faulty piston rings before the engine is wrecked. Anybody working in the engine industry should know this.

Re:It won't work (0)

Anonymous Coward | about 7 months ago | (#45883997)

Anybody working in the engine industry should know this.

Exactly. They know what the hell they are doing, or even if they don't exactly know, they have a hell of a lot better idea of what's going on than you arm-chair engineers. Always naysaying because being a "skeptic" is all the hipster rage these days. I am so glad that an engineer like you could tell us what the functions of a piston's ring are and how a team who knows so much about how a ring works hasn't even thought about the lubrication aspects of their function.

eliminating the piston ring and the associated friction

Oh wait, it's in the TFS. Guess what function of the ring is no longer needed if friction is eliminated? Good thing you posted AC.

Re:It won't work (4, Insightful)

Cryacin (657549) | about 7 months ago | (#45883457)

Trust me, I have a PhD in engineering.

Heh heh. Posting anonymously when resting your authority on the strength of your name rather than the validity of your argument. Have to feed the troll on this one.

Re:It won't work (0)

Anonymous Coward | about 7 months ago | (#45883845)

If I had to pick whom to trust more, AC or Cryacin, I would pick AC. Ignoring my obvious bias, I've made way more posts than you have and for a lot longer too. Again, I am way more trustworthy than you are (especially if you ignore my dissociative identity disorder).

Re:It won't work (1)

Anna Merikin (529843) | about 7 months ago | (#45883869)

No Ph.D. here, but I used to was a mechanic.

TFA is not quite right. Piston ring friction is not the reason an engine needs a cooling system. Quite a lot of heat is produced by the combustion! So much so that the piston rings' are used to transfer heat from the top of the piston to the cylinder wall; typically pistons are made of aluminum alloys which melt around 2000 F. Combustion temps are much. much higher than that. If the metal piston ring didn't conduct heat, the piston would melt.

Solve that with an air seal!

Nice idea but... (-1)

Anonymous Coward | about 7 months ago | (#45883263)

Put ALL effort into engines that don't use fossil fuel at all. Thanks.

Re:Nice idea but... (5, Funny)

megabeck42 (45659) | about 7 months ago | (#45883283)

I'm sorry but the energy density of hopes and dreams is nowhere close to that of gasoline.

Re:Nice idea but... (5, Funny)

Anonymous Coward | about 7 months ago | (#45883293)

But hopes and dreams are of endless supply. Gasoline not so much.

Re:Nice idea but... (2)

Cryacin (657549) | about 7 months ago | (#45883463)

Forget hopes and dreams, power it on a person's sense of self-satisfaction. Although low yield, it's in vast abundance.

Re:Nice idea but... (4, Funny)

ApplePy (2703131) | about 7 months ago | (#45883947)

That's how the Prius works. It's partly powered by smug.

Re:Nice idea but... (1)

cold fjord (826450) | about 7 months ago | (#45883383)

I'm sorry but the energy density of hopes and dreams is nowhere close to that of gasoline.

That's catchy, but I'll reformat it.

I'm sorry but ....
the energy density of hopes and dreams
is nowhere close to that of gasoline.

Re:Nice idea but... (1)

chill (34294) | about 7 months ago | (#45883893)

-1, you forgot "Burma Shave!"

or were you going for haiku format? Too many syllables in that one for a haiku.

Re:Nice idea but... (1)

Anonymous Coward | about 7 months ago | (#45883441)

I'm sorry but the energy density of hopes and dreams is nowhere close to that of gasoline.

I'm sorry but the energy density of gasoline (36 MJ/L) is nowhere close to that of Uranium-235 (1,546,000,000 MJ/L).
Another advantage of Uranium is that while having a lot of oil will get you invaded, carrying even a little bit of Uranium means only another madman would dare approach you.

Re:Nice idea but... (1)

Anonymous Coward | about 7 months ago | (#45883479)

Gasoline's energy density is nothing special, the advantage it has is in procurement, having resulted from millions of years of energy collection which means the effort of getting to it is trivial.

And compared to the alternatives, it's a messy bit of junk.

Re:Nice idea but... (1)

icebike (68054) | about 7 months ago | (#45883621)

Gasoline's energy density is nothing special, the advantage it has is in procurement, having resulted from millions of years of energy collection which means the effort of getting to it is trivial.

And compared to the alternatives, it's a messy bit of junk.

Its pretty special.
Even discounting cost, there are virtually no other fuels that come close.

Re:Nice idea but... (2)

fnj (64210) | about 7 months ago | (#45883995)

It is nothing special from a volumetric energy density (MJ/L) point of view. It's in the same general range as all primarily petroleum based fuels which are liquid at room temperature and atmospheric pressure; more toward the lower end of the range. It is substantially more than liquefied gases and solids such as coal and wood.

Petrodiesel 37.3 MJ/L
Crude Oil 37.0
Gasoline 34.2
Gasohol E10 33.2
Jet A 33.0
Biodiesel 33.0 for comparison

Diesel is both cheaper (in normal countries, not the ridiculous US pricing structure) and higher energy density.

Millions of years of storage, not collection (1)

drnb (2434720) | about 7 months ago | (#45883761)

Gasoline's energy density is nothing special, the advantage it has is in procurement, having resulted from millions of years of energy collection which means the effort of getting to it is trivial. And compared to the alternatives, it's a messy bit of junk.

You are confusing storage not collection. The energy was collected over the very short time span of a plant in a swamp. The millions of years that turns this into crude oil is just chemical transformation and storage.

Gasoline is a simple molecule that can be created in a variety of ways. One way is the distilling of crude oil. Another is biological production via engineered photosynthetic organisms. Same energy source of the fossil fuels, the sun, however carbon is coming from the current atmosphere not carbon sequestered millions of years ago. Its a much greener process.

Re:Millions of years of storage, not collection (1)

koreanbabykilla (305807) | about 7 months ago | (#45883949)

In what universe is gasoline a molecule? I was under the impression it was a mix of various hydrocarbon molecules (among other things).

Re:Nice idea but... (2)

idji (984038) | about 7 months ago | (#45883529)

You sound like the people in my grandmother's village in 1905 when the first car drove in - "It won't last - you can't feed it like you can a horse".

Re:Nice idea but... (1)

icebike (68054) | about 7 months ago | (#45883645)

Are you sure they didn't say you can't BREED it like you can a horse?
If that were the case, they were correct.
Find me two cars you can rub together and get a third, without losing anything from the prior two.
And all for the cost of not mowing your lawn.

Re:Nice idea but... (0)

HornWumpus (783565) | about 7 months ago | (#45883591)

My 'hopes and dreams' are 92% nitro-methane you insensitive clod.

Re:Nice idea but... (1)

chill (34294) | about 7 months ago | (#45883907)

Whereas the majority of other peoples' are between 5% and 50% ethanol.

Re:Nice idea but... (1)

mendax (114116) | about 7 months ago | (#45883493)

Put ALL effort into engines that don't use fossil fuel at all. Thanks.

Exactly, since the internal combustion engine has no future at all in the long term, such a breakthrough is not exactly "news that matters". Now, a great breakthrough in battery technology, or, even better, a nuclear fusion electrical generation station would be something worth thinking about. High storage capacity batteries that can be fully charged in only a few minutes and last for hundreds of kilometers of high-speed driving would kill the internal combustion engine for most vehicles. But nuclear fusion would make energy so cheap that people could still use their internal combustion engines if they really wanted to, but they wouldn't because fuel cell-based cars are mechanically much simpler and more reliable... and should be cheaper.

Re:Nice idea but... (2)

larwe (858929) | about 7 months ago | (#45883975)

Eyeroll. "In the long term we are all dead". For the lifespan of everyone who is alive to read this today (discounting a war that destroys industrial civilization), the internal combustion engine will be the dominant powerplant for transportation. Deal with it.

Re:Nice idea but... (1)

JustOK (667959) | about 7 months ago | (#45883567)

Soylent gas be okay?

Re:Nice idea but... (1)

Ol Olsoc (1175323) | about 7 months ago | (#45883783)

Soylent gas be okay?

Isn't that the solution to pension plan problems and social security?

Re:Nice idea but... (1)

CohibaVancouver (864662) | about 7 months ago | (#45883597)

Put ALL effort into engines that don't use fossil fuel at all. Thanks.

Then effort doesn't go into 'engines' - It goes into energy storage solutions that have the weight / energy capacity of gasoline.

Re:Nice idea but... (0)

VortexCortex (1117377) | about 7 months ago | (#45883831)

Then effort doesn't go into 'engines' - It goes into energy storage solutions that have the weight / energy capacity of gasoline.

Why ignore the inefficiency of internal combustion? Are you seriously saying that putting effort into more efficient motors is advancing energy storage solutions? That sounds imbecilic to me.

Achieving equivalent energy density isn't required if more efficient motors and/or transmission methods are discovered and/or utilized. You're not seriously putting forth that, say, mag-lev trains, or the hyper-loop are applications of "energy storage solutions with the weight / energy capacity of gasoline", are you? Energy density would already be high enough for a hybrid solutions whereby inductive charging supplements existing electric energy storage -- The effort here is going into "energy storage with the weight / energy capacity of gasoline"? No. Not unless you conflate storage with transmission. Take a look next to damn near any road you're driving on for the power line.

Also, burning things should be avoided, not just "fossil fuel". However, better gasoline engines while transitioning to other fuels still helps -- no need for a false dichotomy. Next time don't be absolutists. It makes you both sound like morons.

Re:Nice idea but... (1)

sunderland56 (621843) | about 7 months ago | (#45883641)

Who says it needs to run on fossil fuel? Alcohol runs just fine as a fuel in an internal combustion engine with little modification needed.

Gasoline, diesel, etc don't have to be Fossil Fuel (1)

drnb (2434720) | about 7 months ago | (#45883671)

Put ALL effort into engines that don't use fossil fuel at all. Thanks.

Gasoline, diesel, etc don't have to be Fossil Fuels. We can make them with a biological process for example. These processes are basically carbon neutral since the carbon emitted during internal combustion recently came out of the atmosphere.

Let me be the first to say (2)

bob_super (3391281) | about 7 months ago | (#45883279)

This is 2014, where's my flying car?

Oh wait, I can't afford it.
Please give me grooves for an extra 2 miles a gallon in a way that the local shop can fix (looking at you, battery/hybrid-CVT/regen-braking monster).

Re:Let me be the first to say (1)

hawguy (1600213) | about 7 months ago | (#45883353)

This is 2014, where's my flying car?

Oh wait, I can't afford it.
Please give me grooves for an extra 2 miles a gallon in a way that the local shop can fix (looking at you, battery/hybrid-CVT/regen-braking monster).

My local shop can fix Priuses. Last time I was there with my car (not a Prius), they had one up on the rack for a transmission/transaxle replacement.

Re:Let me be the first to say (0)

AK Marc (707885) | about 7 months ago | (#45883605)

In the old days, if you blew a transmission, the shop could rebuild it while you waited. Now, they wait for a replacement to be flown in, then swap it out.

Re:Let me be the first to say (1)

hawguy (1600213) | about 7 months ago | (#45883775)

In the old days, if you blew a transmission, the shop could rebuild it while you waited. Now, they wait for a replacement to be flown in, then swap it out.

That's true, but that's not limited to Priuses -- when I thought I had a leaking shaft seal in my transmission, they were going to have to send it out to a specialty shop and wait a week for them to rebuild it because they don't rebuild transmissions in-house.

Re:Let me be the first to say (-1)

Anonymous Coward | about 7 months ago | (#45883657)

You misspelled "pussies".

Re:Let me be the first to say (2)

Tablizer (95088) | about 7 months ago | (#45883447)

This is 2014, where's my flying car?

They are working on channeling climate change problems into carnado. It even comes with shark wipers.

Re:Let me be the first to say (0)

DogDude (805747) | about 7 months ago | (#45883537)

Ever look into diesel engines? They're hella' more efficient than gasoline and provide a lot of torque. I don't understand why, but diesel is a simple, cheap, yet dramatic improvement to MPG. My Golf Turbo Diesel gets about 50 MPG and is smokin' fast.

Re:Let me be the first to say (5, Insightful)

bob_super (3391281) | about 7 months ago | (#45883721)

I'm really annoyed at the US car market.
Take any car that is available in Europe, and the only engine you can get here is the biggest one that's available there. I drove on European highways with a 1.1l Fiesta. It won't win any races, but it goes fast enough, and sips fuel. Same car, US side? 1.6l engine. Still pretty good mileage by US standards, but few people would buy it across the pond with the "big" wasteful engine.
Diesel? over 60% of the market in multiple Euro countries. Small HDI engines that give you more oomph than a 2.0l gas one, and torque like a small V6, for two drops of fuel per mile. States-side? Gotta buy a VW/Audi at a premium, or trust GM to have finally made a reliable econobox. For starter, the GM solution with a urea tank is probably not really happy today in the northwest (freezes at 12F according to the web).

So yeah, I'd love a diesel, or a European car, so I can say bye-bye to the fuel pump without lugging batteries and paying a repair premium (and no 10yr resale value). But you can't get them here, because someone decided that Americans NEED MORE POWAAAAR, or something. To drive 65MPH.

Fuel efficiency is nice, but... (5, Insightful)

roeguard (1113267) | about 7 months ago | (#45883313)

Extra fuel efficiency would be nice, but I am most excited about the prospect of the engine itself lasting longer. Less friction = less heat, less wear & tear, etc. A cool, frictionless engine could potentially last for half-million miles before needing replacement. At my paltry 10-20k miles per year, I could potentially never have to buy another car again.

Re:Fuel efficiency is nice, but... (1)

Em Adespoton (792954) | about 7 months ago | (#45883361)

Extra fuel efficiency would be nice, but I am most excited about the prospect of the engine itself lasting longer. Less friction = less heat, less wear & tear, etc. A cool, frictionless engine could potentially last for half-million miles before needing replacement. At my paltry 10-20k miles per year, I could potentially never have to buy another car again.

It'd at least last until your car started failing emissions tests and safety regulations....

Then again, I think that's been my experience for the past 20 or so years, even with the piston rings. Proper maintenance (including the odd part replacement outside the engine) is all a modern car really needs to last for 30+ years.

Re:Fuel efficiency is nice, but... (2, Insightful)

mcrbids (148650) | about 7 months ago | (#45883535)

The question really isn't whether or not it could last 30 years, but rather would you *want* it to?

I drive a 2001 convertible. It's not a bad car, and runs as if it were new. It has all the luxury options: automatically dimming rear view mirror, leather seats, Bose Infinity speakers, 200 HP engine, etc. I've taken excellent care of it, regular oil changes, fix any problems before they escalate, etc. Even so, it's near the end of its being interesting to me. Its styling is looking pretty passe, the electronics are getting to be really dated, (who even has a CD collection any more?) etc.

Yes, I could (and have) upgraded components. I've replaced the headlight casings because they were turning yellow, etc. and the radio is probably next. Sadly, there's nothing I can do about the 5 disc CD changer, even if I replaced the radio, I'd still have that funny looking husk down in front of the shifter knob.

Nothing changes the fact that it's getting to be an old car.

Re:Fuel efficiency is nice, but... (4, Funny)

Anonymous Coward | about 7 months ago | (#45883699)

Nothing changes the fact that it's getting to be an old car.

Yes, yes this is exactly what we want you to think.

Thanks,

The Auto Industry

Re:Fuel efficiency is nice, but... (1)

HornWumpus (783565) | about 7 months ago | (#45883743)

Take a good hard look at new cars.

Touch screen controls, throttle by wire, even more plastic then your 2001.

You should be able to afford a really nice older car by now. No more payments bullshit.

Corvettes of many years are interesting. Original ZR1? Any pre-disco 'vette.
Jag E types with the six have all the styling and much less unreliability vs. the V12s. Still Lucas electrics and English, so wear good walking shoes.
77 7.3 super duty TA?
Last gen RX-7?
Original Audi Quattro?
GMC Syclone/Typhoon?
71 Honda 600N?
NSX?

Depends on your budget and taste. Different bores and strokes...some people even like Fords. So many nicer choices among old cars, all new cars look alike.

Re:Fuel efficiency is nice, but... (1)

AK Marc (707885) | about 7 months ago | (#45883659)

I had a '67 Bug. Nearly everything is grandfathered. That car didn't have seatbelts, but was still legal. It wasn't require to pass emissions (it was too old), but the shop would run it anyway for fun, it always passed modern tests. In a pre-cat car 40+ years old. So it didn't need to be tested, and even if it were, it would have passed.

And safety regulations allowed it to be seatbeltless, as it came that way from the factory. And a non-compressible steering column, and "bad" bumpers, and all that. Perfectly legal to keep on the road, even if impossible to sell new.

Re:Fuel efficiency is nice, but... (0)

Anonymous Coward | about 7 months ago | (#45883391)

The Auto Industry would never have that. Planned obsolescence is the current MBA business model.

Re:Fuel efficiency is nice, but... (0)

Anonymous Coward | about 7 months ago | (#45883489)

No kidding. It's not just the auto industry either. Try buying a jacket or sweater that doesn't have a piece of shit zipper that breaks in less than a year, basically forcing you to buy a new jacket (most of them are designed in such a way that sewing a new zipper on just doesn't work right, and any new zipper you buy is also a piece of shit).

Fuck the zipper companies! Fuck them in their greedy asses!

Re:Fuel efficiency is nice, but... (1)

50000BTU_barbecue (588132) | about 7 months ago | (#45883533)

Try spending more than 99$ for a Made in China generic coat. I paid 600$ for a Canadian-made Nylon-shell winter coat with nice synthetic filler. It's 12 years old so that's 50$ per year. The only sign of wear is on the cuffs, looking a bit threadbare but I can bring it to the store and they'll sew in new ones.

Re:Fuel efficiency is nice, but... (1)

newcastlejon (1483695) | about 7 months ago | (#45883573)

Can't I just spend 109$ on a serviceable coat with a premium zip?

Re:Fuel efficiency is nice, but... (2)

Martin Blank (154261) | about 7 months ago | (#45883653)

I hear people complaining about this as much as ever, but cars are lasting a lot longer now than they used to. It wasn't all that long ago that a car that reached 100,000 miles was sold off or traded in as a junker. Now, any car that can't reach 200,000 miles at a minimum (with moderate care) is considered to be of poor quality. Maintenance itself is getting easier, with longer times between oil changes, tune-ups, and other general maintenance. Hell, even tires are lasting considerably longer.

Re:Fuel efficiency is nice, but... (2)

Ol Olsoc (1175323) | about 7 months ago | (#45883897)

The Auto Industry would never have that. Planned obsolescence is the current MBA business model.

I do not know how old you are, but when I was a kid, cars were nothing like they are today. A lot of people bought new cars every two years. And if you got 100 K miles on a vehicle, you did well, and the vehicle was just about finished.

As the years went by, there were many improvements in both the mechanics and structures of the vehicles. My first car, a 1965 Buick Skylark, had a lot of work done to it to repair rust at 70K miles. That was typical.

When I was a gear head way back when, we would some times blueprint and balance an engine. Tear it apart, make certain that every part was as close to optimal as possible, and balance the crankshaft and reassemble the engine. Today, they come from the factory in as good shape. Today, people regularly get 200K plus miles on their vehicles. I did that in a Jeep Grand Cherokee, a Suzuki Vitara V6 and a Nissan Pulsar so far. I expect my 2 present Jeeps to do the same.

Which is why today, people usually get bored with their rides before they wear out.

Re:Fuel efficiency is nice, but... (0)

Anonymous Coward | about 7 months ago | (#45883449)

Even now you can just replace cylinders. It's called top overhaul. General aviation folks do it all the time. Car owners rarely - most want a new car, I guess.

Re:Fuel efficiency is nice, but... (0)

Anonymous Coward | about 7 months ago | (#45883503)

LoL -- less heat/friction/wear will ultimately mean this: Manufacturers will find less expensive ways to make an engine that will have essentially the same wear/lifespan characteristics as current engines. They will continue to charge the same (or more fer all teh new hi-tek futuristy nifty-keen engi-ma-thingy stuff) and then walk away laughing at higher profit margins. Per the modern economic paradigm, it will be the corporations and their wealthy benefactors that profit from this more than anyone or anything else...

-AC

Re:Fuel efficiency is nice, but... (2)

HornWumpus (783565) | about 7 months ago | (#45883809)

Do you know how I can tell you're a kid?

Do you think gas powered cars have always run 250K between engine rebuilds? (That's mostly down to hard chrome plated piston rings.)

When I started driving you got 100K between engine rebuilds.

When my dad started driving you got 40K between engine rebuilds.

Re:Fuel efficiency is nice, but... (1)

beelsebob (529313) | about 7 months ago | (#45883557)

Except engines aren't the things that cause you to buy a new car. The chassis rusting through, or the plastic components all rotting simultaneously, or the suspension beginning to go, or a whole bunch of small things adding up... These are the kind of things that cause you to buy a new car.

Re:Fuel efficiency is nice, but... (0)

Anonymous Coward | about 7 months ago | (#45883849)

This.

We just unloaded our 1994 Jetta for $300 at a scrap dealer. The engine was perfectly line. Even the transmission was fine.

The front passenger suspension was going and "clunked" on potholes, speedbumps, etc. It had a never ending series of coolant leaks (fix one, it sprung another...). The sunroof retraction mechanism was broken (and parts were impossible / expensive) so we couldn't use the sunroof. The rear passenger door handle inside latch broke, and was too expensive to fix unless we found a matching scrapyard part. The trunk release button was worn at the trunk and unreliable (but the glovebox trunk release was fine still). The ventilation fans had worn bearings and were noisy when we had to run the heater. The seat springs in the driver seat were starting to go.

It had also picked up plenty of scratches over the years, and a more major scrape from concrete pole in a parking garage some years ago. (Would have cost a few grand to fix properly and repaint half the car...) but it was all just cosmetic.

20 years old. The drive train was fine, the tires and brakes were fine, it passed emissions no problem... but it was falling apart and just wasn't worth fixing. It was closing in on 360,000km.

Re:Fuel efficiency is nice, but... (1)

TubeSteak (669689) | about 7 months ago | (#45883723)

Extra fuel efficiency would be nice, but I am most excited about the prospect of the engine itself lasting longer.

Buy a diesel.
For a light duty diesel truck engine, 300,000 miles is considered the 50/50 point where you *might* have to fix stuff that's starting to wear out.
For industrial/heavy diesels, they can more or less run forever as long as you keep changing the fluids.

My understanding is that gasoline engines are generally not overbuilt for strength, otherwise they'd have the same service life as diesels.

Re:Fuel efficiency is nice, but... (1)

icebike (68054) | about 7 months ago | (#45883875)

Extra fuel efficiency would be nice, but I am most excited about the prospect of the engine itself lasting longer. Less friction = less heat, less wear & tear, etc. A cool, frictionless engine could potentially last for half-million miles before needing replacement. At my paltry 10-20k miles per year, I could potentially never have to buy another car again.

What do you think is going to keep those pistons centered and friction-less? And where is the heat of combustion going to go?
At 10 to 20K a year you may already never need to buy another car, you just WANT one.
Modern cars have no particular problem reaching 200,000 miles, and even 300k.

The wear that piston rings impose is undone by a ring job. Used to be able to get that done at the corner garage without a great deal of hassle or money, but now days it costs around $2000 bucks do to the complexity of modern engines. Still cheaper than a new car.

Re:Fuel efficiency is nice, but... (2)

im_thatoneguy (819432) | about 7 months ago | (#45883919)

When I was driving around an '86 golf I was considering upgrading the engine since the old VWs made that a trivial affair. I'm sorry to report that you can buy a brand new engine for a few thousand dollars. It's rarely "the engine" which gives out in a car. It starts with the door handles breaking off, the dash getting smashed, the bumper starting to rust and then you get into the really expensive stuff like transmission and random engine bits.

If you just want to drive the same car with a well running engine block you could reach your half million miles for about an extra $3k today.

Re:Fuel efficiency is nice, but... (1)

the eric conspiracy (20178) | about 7 months ago | (#45883963)

I've never had an engine fail due to piston ring wear.

Seems to me this may be an idea looking for a problem.

I See A Problem (1)

CanHasDIY (1672858) | about 7 months ago | (#45883347)

So, the idea is that the grooves in the piston will create little eddies of air that separate the combustion chamber from the oil galley, right?

Here's the problem - the air that forms said eddies has to come from somewhere, and there's only two options: the combustion chamber, or the oil galley.

Still, to a gear head such as myself, it's still a pretty cool idea.

Re:I See A Problem (1)

Wing_Zero (692394) | about 7 months ago | (#45883471)

from TFA

That means theres no metal-to metal contact between the pistons or rotors and their mating cylinders or housings. Virtually no friction means the mechanism needs no lubrication and there is no wear and tear on major components said Trigg.

My understanding is no lubrication = no oil galley under the piston. this part scares me more than no piston rings. I have a 97 chevy pickup that had 2 bad o2 sensors when i bought it and was running a VERY rich fuel mix, throwing soot into the crankcase, (i don't believe it has a leak, after 2 oil changes, the oil had a normal breakdown color, and I don't burn any oil either)

Should such a error occur in this type of engine, and no lubricant, what is stopping the soot from gumming up the moving bits?

Re:I See A Problem (1)

Cramer (69040) | about 7 months ago | (#45883847)

It'll still have an oil pan, and several quarts/litres of oil. The rings are only one of many places where things touch. Also, that oil is one of the things cooling the piston. (and in my car, cooling the turbo)

Re:I See A Problem (1)

msauve (701917) | about 7 months ago | (#45883505)

One would think that a self-proclaimed "gear head" would know the difference between an oil galley [sic] and a crankcase.

Re:I See A Problem (1)

Cramer (69040) | about 7 months ago | (#45883835)

Or even "oil pan"...

Re:I See A Problem (1)

Ol Olsoc (1175323) | about 7 months ago | (#45883961)

So, the idea is that the grooves in the piston will create little eddies of air that separate the combustion chamber from the oil galley, right?

Here's the problem - the air that forms said eddies has to come from somewhere, and there's only two options: the combustion chamber, or the oil galley.

Still, to a gear head such as myself, it's still a pretty cool idea.

It is cool. You're right about the eddies having to come form somewhere. I think, from reading the article, (sorry slashdot Gods) that the eddiese are frmo the fuel -air mixture, as they talk about a stratified charge happening.

Anyhow, the concept is fairly sound - I think - my concerns are regarding cold to hot operation, and starting.

At least it's not like the goofy Magnets pulling on pistons crap some scammers have been trying to feed us.

Okay...nice and all... (2, Informative)

Mashiki (184564) | about 7 months ago | (#45883363)

But we already have an engine that doesn't use piston rings. [wikipedia.org] And it's not like this idea hasn't been tried before either on reciprocating piston engines, usually with a whole series of problems. Mostly compression issues.

Re:Okay...nice and all... (2)

plover (150551) | about 7 months ago | (#45883401)

Right, because the seals along the rotor don't do exactly the same thing as piston rings, only less effectively.

Re:Okay...nice and all... (5, Informative)

stepho-wrs (2603473) | about 7 months ago | (#45883403)

Wankel apex seals are the equivalent of piston rings - ie a chunk of metal/ceramic that fills the gap between the piston/rotor and the chamber wall.

Re:Okay...nice and all... (1)

cold fjord (826450) | about 7 months ago | (#45883405)

TFA mentions that they are working on a variant for a rotary engine as well.

Re:Okay...nice and all... (0)

Anonymous Coward | about 7 months ago | (#45883433)

The apex seals of a wankel rotary engine basically serve the same purpose as piston rings. They are seals that directly contact the piston/rotor housing.

Re:Okay...nice and all... (2)

HornWumpus (783565) | about 7 months ago | (#45883861)

Ringless engines are common: 2 stroke model airplane engines.

You mill the piston sleeve from the bottom, so tool runout leaves a slight taper. Then you hard chrome one side of the piston/sleeve combination. When you break it in the hard side wears the soft side to match 'perfect', with the seal tightening at the top of the stroke.

They run a little dirty and aren't exactly long lived.

On paper (1)

Tablizer (95088) | about 7 months ago | (#45883417)

Mind you, they haven't even built a working prototype yet.

Only works in theory? Don't tell me, rubber pistons? [slashdot.org]

funding for bringing to market? (4, Insightful)

bloodhawk (813939) | about 7 months ago | (#45883419)

If they haven't even built a working prototype then how can they be seeking funding to bring it to market? surely they are just seeking funding to prototype to see if it is even viable to bring to market?

Now all we need... (0)

Anonymous Coward | about 7 months ago | (#45883431)

Is the no ring design coupled with a spherical rotary head. What ever happened to Coates International?

labyrinth seals (0)

Anonymous Coward | about 7 months ago | (#45883467)

They are re-inventing labyrinth seals. They come in a variety of shapes and sizes. They've been used for decades in jet engines and other applications where the pressure drop across the seal in not large. They have not proven practical in applications with higher pressure drops across the seal because they don't seal completely. There is always some leakage.

Down under? (1)

Tablizer (95088) | about 7 months ago | (#45883475)

They shouldn't test in Australia. Down there, piston engines convert smog into petroleum.

Wait, what? (5, Insightful)

DerekLyons (302214) | about 7 months ago | (#45883481)

From TFA:
 

Dynex has brought the technology to the proof-of-concept phase, in which virtual modelling of the âoeair-sealingâ principle looks promising enough to get to work on the real thing.

A 'virtual model' equates to 'proof-of-concept'? Since when?

Re:Wait, what? (0)

Anonymous Coward | about 7 months ago | (#45883771)

Proof-of-concept: A proof of concept or a proof of principle is a realization of a certain method or idea to demonstrate its feasibility, or a demonstration in principle, whose purpose is to verify that some concept or theory has the potential of being used.

The virtual models says it's at least feasible and has a potential of actually being used, so now they spend a crapload of money building a single iteration of the piston they simulated.

Why not eliminate the piston too? (3, Interesting)

scorp1us (235526) | about 7 months ago | (#45883507)

I thought this was about this article [newscientist.com] which uses a pistonless pressure wave and makes all the same promises.

Already done? (0)

Anonymous Coward | about 7 months ago | (#45883523)

My reading comprehension may be failing me here. Does the article say Benz and BMW are already using this technology?

"It’s the ideal set-up to make the most of each spark, already used in advanced engines by the likes of Benz and BMW for the win-win it produces in boosting performance while cutting consumption and emissions."

Interesting (1)

wbr1 (2538558) | about 7 months ago | (#45883531)

But no prototype. I am not a physicist, but I ran it through a little thought experiement. If it is some sort of standing pressure wave, it would have to move with the piston, that may be possible, but difficult. The problem I see is that any type of wave would hbe dependent on the frequency/speed of the piston in the cylinder. Therefore, it would have to be there across the entire operating range of the engine, not just it's peak power band. That is a large range. If it falls off anywhere along this range then you get oil control issues, compression issues, or both just as if you had bad rings. Oil control leads to plug/combustion chamber issues and expensive oil replacement. Compression issues lead to huge ineffeciencies, that would offset some or all of the gains from reducing friction. In addition, while the friction may be less, this pressure wave would by its nature have to exert some pressure on the piston and cylinder walls to seal. It may be less friction and less metal to metal contact, but not zero friction. In short a laudable goal, but seems more like a funding grab than a workable idea.

Why are they developing a new engine? (1)

Radical Moderate (563286) | about 7 months ago | (#45883643)

Seems like a lot of extra work. Why not just mod an existing design with their piston?

But... But... But... They're AUSSIES! (0)

Anonymous Coward | about 7 months ago | (#45883711)

That makes this Slashdot-worthy.

Ringland + STi (0)

Anonymous Coward | about 7 months ago | (#45883713)

A boxster engine.... are they looking to fix the Subaru STi ringland problem ? Some stock and modified Subaru STi haves piston rings failures from cylinder 2 and 4.

I can't see that it will be beneficial. (1)

Virtucon (127420) | about 7 months ago | (#45883879)

You'd have to keep the CR low enough to not overcome the pressure wave of the ringless design. That means you'd lose efficiency in the engine. Reducing friction is a great concept but I'd still like to see the math involved as to how they'd get the efficiency out of the engine vs. a traditional design and how they'd keep the crankcase temps down and the oil clean. Most of that black/brown gunk in your oil at an oil change is blow-by, products of the combustion process. Even with piston rings you get a certain percentage of this and it raises the temps of the engine not just with friction but with hot gasses escaping into the crankcase. Don't get me wrong, I'd love to see internal combustion go beyond what we have today but it seems that there are already advances in direct injection and forced induction that are making smaller more efficient designs more powerful. If you want an internal combustion engine without rings (or wipers in a Wankel) then why not a turbine engine? It was tried before [wikipedia.org] but I guess people were worried about melting the asphalt with the exhaust gas temps.

Re:I can't see that it will be beneficial. (0)

Anonymous Coward | about 7 months ago | (#45883981)

The problem with turbines is they aren't efficient at idle and they don't like constantly changing rpms. To make one work well you would need a CVT and a hybrid drive to handle stop and go and low speeds.

Not a new idea, and unlikely to be adopted. (0)

Anonymous Coward | about 7 months ago | (#45883885)

The biggest barrier to the adoption of ringless pistons is pre-existing technology
which is mature ( and works as needed ) and which has already paid for its development costs.

Billions of dollars and millions of man-hours have been consumed
in the development of Otto Cycle engines. Existing engines do not fail
because the piston rings are worn. They most often fail due to poor maintenance
practices, negligence, or abuse, which would kill an engine using ringless pistons just as quickly.

Additionally, whether this ringless technology is adopted hinges on
whether money is made available to develop it to the point where it
can be used in mass-produced vehicles. When a manufacturer can
meet its goals using an engine which has piston rings and spend less
money , or spend significantly more money using ringless pistons
which give marginal improvements at best, it is extremely unlikely that
a manufacturer will choose the ringless technology which involves more
risk for a reward which is not proportional to the risk.

There is an old patent on such ringless tech. There really are
very few new ideas in internal combustion engine tech.

http://www.google.nl/patents/US3745890

Much larger gains in power and efficiency are available by using electrical
or pneumatic devices instead of camshafts to control the movement
of valves in an engine. If I had to bet on what would be the most likely
tech to actually be used in production engines this is where I'd put my
money. Such tech IS used in engines of both Formula 1 cars and MotoGP
racing motorcycles. But all those engines ( on which hundreds of millions of
development dollars / Euros / yen have been spent ) still use piston rings.
That ought to tell you something. Of course it is possible that the engineers
at Ferrari and Honda and Renault and BMW are not as sharp as the folks in
Australia with their ringless pistons, but smart money would not bet on that
being the case.

Finally, if you REALLY want your engine to last, use the best synthetic oil available
and perform all other maintenance as indicated by the manufacturer, and you will
probably get bored with the vehicle long before it wears out.

=

This is an old idea (5, Interesting)

larwe (858929) | about 7 months ago | (#45883891)

Turbulent obturation rings of this kind (well, technically I guess these are obturation cannelures) have been used in a lot of applications because they have some interesting properties. For instance they are used in mortar shells. When you drop the shell down the mortar barrel, you essentially want it to fall without retardation so the primer gets a good hard strike and the propellant ignites 100% of the time. However you want as much as possible of the propellant gas to do the job of propelling the projectile, without blowing past it in the barrel. You ALSO want it to be as consistent as possible so the CEP of where the projectile lands relative to the target is as small as possible. So this isn't impossible, but it's not easy either.
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