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Heat Engines Shrunk By Seven Orders of Magnitude

kdawson posted more than 4 years ago | from the gimme-a-v8-of-those dept.

Power 168

KentuckyFC writes "The vast majority of motors that power our planes, trains, and automobiles are heat engines. They rely on the rapid expansion of gas as it heats up to generate movement. But attempts to shrink them by any significant amount have mostly ended in failure. Today, the smallest heat engines have a volume of some 10^7 cubic micrometers. Now group of Dutch engineers has built a heat engine that is seven orders of magnitude smaller than this. The engine consists of a piezoelectric bar that expands and contracts in the normal piezoelectric way. However it also heats up and cools at the same time causing a thermal expansion and contraction, which lags the piezoelectric displacement. By carefully choosing the frequency of the driving AC current, the Dutch team found a resonant effect in which the thermal expansion and contraction amplifies the mechanical motion, making it a true heat engine. Operating the thermodynamic cycle in reverse turns the device into a heat pump or refrigerator. The total volume of the device is just 0.5 cubic micrometres."

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168 comments

what about my car... (2, Funny)

Azmodan (572615) | more than 4 years ago | (#30859840)

Great, let's make this 500 times bigger and power my car!

Re:what about my car... (3, Funny)

Parlett316 (112473) | more than 4 years ago | (#30859866)

Yeah a Beowulf cluster of them

Re:what about my car... (-1, Troll)

Anonymous Coward | more than 4 years ago | (#30859880)

If the average Slashdotter's micropenis [wikipedia.org] was about 10,000 times bigger, it might approach the size of this new heat engine. Then you could break out the tweezers you faggots!

Re:what about my car... (1)

von_rick (944421) | more than 4 years ago | (#30859940)

Don't do it unless you know the efficiency of this heat engine. Something tells me that a micro engine (or an array of those micro engines) wouldn't help you much.

Re:what about my car... (1)

floppycat (1592023) | more than 4 years ago | (#30860298)

The vast majority of motors that power our planes, trains, and automobiles are heat engines...Today, the smallest heat engines have a volume of some 10^7 cubic micrometers.

If engine of your car is much bigger than that, you should consider replacing your car.

Re:what about my car... (1)

bluefoxlucid (723572) | more than 4 years ago | (#30861360)

0.215 millimeters width, length, and depth?

On Chip cooling? (1, Insightful)

camperdave (969942) | more than 4 years ago | (#30859858)

Operating the thermodynamic cycle in reverse turns the device into a heat pump or refrigerator. The total volume of the device is just 0.5 cubic micrometres.

Great! When can I get these built into my CPUs?

Re:On Chip cooling? (3, Insightful)

Anonymous Coward | more than 4 years ago | (#30859904)

It's not like a heat pump turns heat into nothing. One side of a heat pump gets cold, the other side gets hot. At half a micron across, it's hard to see how such a device could help evacuate heat from a CPU.

Re:On Chip cooling? (1)

AaxelB (1034884) | more than 4 years ago | (#30859964)

It's not like a heat pump turns heat into nothing. One side of a heat pump gets cold, the other side gets hot. At half a micron across, it's hard to see how such a device could help evacuate heat from a CPU.

Just stick 100,000 of them end-to-end, naturally. Of course, I've no idea how efficient or effective they really are, but it seems like it *could* work.

Re:On Chip cooling? (1)

MozeeToby (1163751) | more than 4 years ago | (#30860006)

Stack arrays of them on top of each other between the CPU and the heat sync. Even if the temperature gradient is tiny over each layer it will add up, and even 1000 of them would be less than a millimeter thick.

Re:On Chip cooling? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#30860546)

"heat sync" ?! Does anyone actually understand what they talk about these days, or do words just get conflated in the cloud?

Re:On Chip cooling? (1)

dosilegecko (1609441) | more than 4 years ago | (#30860820)

I'm sure they meant heat sink, or a sink where the water comes out heated.

Re:On Chip cooling? (0)

Anonymous Coward | more than 4 years ago | (#30860158)

The way it was explained to me is you make an array of them. Or more in a 'trouble spot'.

Most of the problems with heat is getting it to the heat sink. This sounds like a nice way to do it even when they were talking about it 20 years ago.

The trick has been making them small enough and the ability to actually make them in bulk.

Thermal paste (which is really as good as we get in consumer grade stuff) works pretty good. But this would work even better.

Re:On Chip cooling? (4, Interesting)

coolsnowmen (695297) | more than 4 years ago | (#30860168)

Already done: see peltier device. They are already made to the correct size and probably better efficiency.
http://www.peltier-info.com/ [peltier-info.com]
http://en.wikipedia.org/wiki/Thermoelectric_cooling [wikipedia.org]

Re:On Chip cooling? (4, Insightful)

ElectricTurtle (1171201) | more than 4 years ago | (#30860872)

It always amuses me when people try to raise performance as a point against a first generation lab prototype vs. a tenth generation refined technology in production. The question is not whether these piezoelectric heat engines/pumps are more efficient than peltiers now, but rather can they be more efficient than peltiers in the future after further development, or is there a foreseeable upper limit to the technology that makes such an application unlikely even with development?

There *is* a need for heat reduction at very small scales, especially in mobile devices or even the implant devices of the future. Of course heat has to go somewhere, the only issue is that the destination of the heat be better able to deal with it than the source.

Re:On Chip cooling? (1)

hrimhari (1241292) | more than 4 years ago | (#30861432)

Last time I checked, no cooler actually tried to turn heat into nothing but rather divert the heat from where it's being actively produced to a place that it can be efficiently dissipated.

If one can force the heat transfer to go faster than it naturally would, the implications on CPU cooling are obvious.

Re:On Chip cooling? (1)

Shadow of Eternity (795165) | more than 4 years ago | (#30859906)

If it's anything like pretty much every other really useful technological development that's occured in the last decade? You probably won't, but they'll always say it's N years away from commercial application.

Also they mention the ability to use it for refridgeration, but not whether it's still moving when they do that. Even on a microscopic scale having these things moving pretty much anywhere could cause problems.

Re:On Chip cooling? (1)

m509272 (1286764) | more than 4 years ago | (#30860096)

Was the first thing that popped into my head too. Of course, depends on many factors I'm sure.

Next step (0)

Anonymous Coward | more than 4 years ago | (#30859870)

a micro SUV

Re:Next step (1)

ElSupreme (1217088) | more than 4 years ago | (#30860424)

You mean a hatchback?

Re:Next step (1)

tom17 (659054) | more than 4 years ago | (#30860734)

Or rather a SUV is just a bigger Hatchback.

Another way to save gas (1)

MrJones (4691) | more than 4 years ago | (#30859900)

Its a heat engine but it does not use gas, so maybe this could be the engine for a train of nano bots! Or we can use them to cool our CPUs. Interesting indeed, now we need to find an use for it

Re:Another way to save gas (3, Funny)

mcgrew (92797) | more than 4 years ago | (#30860440)

If the heat were produced externally it would be a sort of Stirling engine. So I guess one this size would be Sterling sliver.

what is a cubic micrometer (1, Funny)

Anonymous Coward | more than 4 years ago | (#30859910)

Can the physics gurus please put cubic micrometers in perspective for us common mortals? Is that as big as a grain of rice or a head of a pin?
10^7 micrometers is.... a spehrical cow? a toaster?

Re:what is a cubic micrometer (5, Informative)

Red Flayer (890720) | more than 4 years ago | (#30860012)

You know how big a millimeter is, right? A micrometer is one thousandth the length of a millimeter.

A cubic micrometer is the volume occupied by a cube one micrometer on each side.

10^7 cubic micrometers would fill a cube about one-fifth of a millimeter on a side. Smaller than a pinhead.

Re:what is a cubic micrometer (3, Informative)

xaxa (988988) | more than 4 years ago | (#30860234)

about one-fifth of a millimeter on a side

That's about the thickness of a sheet of paper. (Round here, and probably in a lot of the world, the thickness and density of paper is specified, for instance "160 g/m^2, 200 micrometres".)

Re:what is a cubic micrometer (1)

ilsaloving (1534307) | more than 4 years ago | (#30860626)

How many libraries of congress is that?

Re:what is a cubic micrometer (0)

Anonymous Coward | more than 4 years ago | (#30860854)

How many libraries of congress is that?

What?

That's like sitting in some bleachers, looking down at a football field, and asking how many GHz it is.

Major standard non-standard unit misuse, man.

Re:what is a cubic micrometer (4, Funny)

Thud457 (234763) | more than 4 years ago | (#30861450)

WRONG!

Library of Congresses are a perfectly cromulent unit of volume. Just because the necessary measurements to derive the value are not easily google-able doesn't invalidate that fact.

In the past, when deriving the conversion from Library of Congresses to BTU's, we've used the assumption that we're talking about the books that make up the Library of Congress, not the building itself. This is because, back in the mists of time, Library of Congresses were originally used as a measure of information in the collection of the Library of Congress.

Anyhow, as a back-of-the-envelope estimate, 29 million books [wikipedia.org] at 1" x 10" x 8" gives us a value of ~50,000 cubic yards. That gives us a value of ((10^7) (cubic micrometers)) / (50 000 (cubic yards)) = 2.61590124 × 10-16 [google.com] Library of Congresses.

Screw this "metric system" with it's plethora of different units for different quantities. I strongly endorse that everybody normalize on Library of Congresses for units of any quantity. Just imagine how it would simplify your life!

Re:what is a cubic micrometer (0)

Anonymous Coward | more than 4 years ago | (#30860722)

Much smaller I guess. But that was the previous minimum, right? So the summary is saying "attempts to shrink them by any significant amount have mostly ended in failure" because they couldn't make them smaller than a fraction of a pinhead?! Wow!

Re:what is a cubic micrometer (1)

MagicM (85041) | more than 4 years ago | (#30860802)

(10^7) (cubic micrometers) = 0.01 cubic millimeters

Re:what is a cubic micrometer (1)

mdda (462765) | more than 4 years ago | (#30861042)

What's INSANE about this is that the tiny heat pump that's one-fifth of a millimeter on a side is HUGE (10^7 times as big) in comparison to the one these guys are making.

Re:what is a cubic micrometer (4, Informative)

Atraxen (790188) | more than 4 years ago | (#30860074)

Fun fact - Wolfram Alpha can serve as your 'self-checkout line' for things like this.
http://www.wolframalpha.com/input/?i=1+cubic+micrometer [wolframalpha.com]

Here's a bit of scale - a cubic micrometer is about the same size as a calibration bead for microscopy. A red blood cell is about 8 micrometers across. http://learn.genetics.utah.edu/content/begin/cells/scale/ [utah.edu] Or, there's this video showing the "powers of ten" (also its title...): http://www.youtube.com/watch?v=A2cmlhfdxuY [youtube.com]

Also, chemists work at these dimensions, too! (So do biologists. And others.) :*P Don't snub the other disciplines!!! Or I'll weep. And not gently, nor to a guitar.

Re:what is a cubic micrometer (1)

DeltaStorm (118517) | more than 4 years ago | (#30860512)

Can the physics gurus please put cubic micrometers in perspective for us common mortals? Is that as big as a grain of rice or a head of a pin?
10^7 micrometers is.... a spehrical cow? a toaster?

Yes, someone explain how many of them would fit into the library of congress.

Re:what is a cubic micrometer (3, Funny)

IndustrialComplex (975015) | more than 4 years ago | (#30860616)

Yes, someone explain how many of them would fit into the library of congress.

A metric assload.

Re:what is a cubic micrometer (4, Funny)

iapetus (24050) | more than 4 years ago | (#30860786)

That's no help - most Slashdotters are American. What's that in imperial assloads?

Re:what is a cubic micrometer (1)

MadKeithV (102058) | more than 4 years ago | (#30860894)

A lot less, due to size-differences between the US and Europe.

Re:what is a cubic micrometer (1)

vasp (978274) | more than 4 years ago | (#30860974)

Just about 0.62 imperial assloads.. or ca 1.2 imperial cheekloads.

Re:what is a cubic micrometer (0)

Anonymous Coward | more than 4 years ago | (#30861062)

I don't know, but I hear Queen Victoria had *quite* the imperial ass.

Re:what is a cubic micrometer (2, Informative)

mdm-adph (1030332) | more than 4 years ago | (#30861262)

That's "U.S. Customary [wikipedia.org] " assloads, Loyalist swine.

Did someone say pump? (1, Funny)

Anonymous Coward | more than 4 years ago | (#30859928)

Can it be used for other things?

Re:Did someone say pump? (3, Interesting)

Areyoukiddingme (1289470) | more than 4 years ago | (#30861186)

If you've got a thing that small, it's time to give up on it...

Beer cans? (1, Funny)

courteaudotbiz (1191083) | more than 4 years ago | (#30859930)

How many beer cans fit in a 0.5 micrometers refrigerator?

Re:Beer cans? (4, Funny)

AaxelB (1034884) | more than 4 years ago | (#30859972)

How many beer cans fit in a 0.5 micrometers refrigerator?

Depends. Are we talking micro- or macrobrews?

Re:Beer cans? (1)

courteaudotbiz (1191083) | more than 4 years ago | (#30860010)

Sorry, I didn't specify. I was talking about nanobrews.

Re:Beer cans? (0)

Anonymous Coward | more than 4 years ago | (#30860594)

Then a 1000x1000x1000. You silly Americans really can not do anything for yourselves.

Re:Beer cans? (1)

courteaudotbiz (1191083) | more than 4 years ago | (#30860636)

I am Canadian, you insensitive clod!

And since we're talking about .5 micrometers, it would be more like 1000x1000x500.

You also forgot about the nano light-bulb, otherwise, you won't be able to see the beer in the fridge...

Re:Beer cans? (0)

Anonymous Coward | more than 4 years ago | (#30861018)

Stop being pedantic. We're talking about beer here!!!!

Re:Beer cans? (1, Funny)

Red Flayer (890720) | more than 4 years ago | (#30860046)

How many beer cans fit in a 0.5 micrometers refrigerator?

You're thinking too small.

The correct question is, how many beer kegs fit in a 0.5 micrometer fridge?

Re:Beer cans? (4, Funny)

krnpimpsta (906084) | more than 4 years ago | (#30860488)

You're thinking too small.

The correct question is, how many beer kegs fit in a 0.5 micrometer fridge?

0.00000000000000000852167911 beer kegs

If the fridge interior happens to be shaped optimally so that no space is wasted and the entire 0.5 micrometer fridge is filled with keg, then.. exactly 8.52167911 * 10^-18 beer kegs (if each keg is 15.5 gallons). [Incase someone wants to out-pedant me: Yeah, I understand you can't optimally shape a 0.5 micrometer fridge for a keg, when the size of 1 unit of keg > 0.5 micrometer fridge.]

Citation: http://www.google.com/search?hl=en&q=(0.5+micrometers%5E3)%2F(1+keg)&aq=f&aql=&aqi=&oq= [google.com]

Re:Beer cans? (0)

Anonymous Coward | more than 4 years ago | (#30861216)

You, sir, are my hero.

Re:Beer cans? (1)

damien_kane (519267) | more than 4 years ago | (#30861442)

The correct question is, how many beer kegs fit in a 0.5 micrometer fridge?

The answer is None... None beer kegs fit in a 0.5 micrometer fridge.
One fits nicely in my kegerator, though.

Re:Beer cans? (1)

mcgrew (92797) | more than 4 years ago | (#30860400)

That depends. Are we talking about actual beers? [angryflower.com]

In a less huumorous vein, how many of these refrigerators does it take to cool a can of beer? It would be nice to have cold beer with a built in refrigerator in every can. Provided it could be done cheaply enough.

Usefulness? (1)

robinstar1574 (1472559) | more than 4 years ago | (#30859950)

This is a great invention, but how can it be used in a meaningful way? It is so small that it produces a very minimal amount of horsepower, which is not useful for any actual way.

Re:Usefulness? (5, Funny)

Dunbal (464142) | more than 4 years ago | (#30860044)

It is so small that it produces a very minimal amount of horsepower, which is not useful for any actual way.

      Unless of course you have several billion of them on a gram sized object. If you can't see the value in jet powered ants you should turn in your nerd card.

Re:Usefulness? (1)

tmosley (996283) | more than 4 years ago | (#30860838)

Finally, a refrigeration unit compact enough to let me get some sharks with frikkin' lasers on their heads!

Re:Usefulness? (5, Interesting)

gurps_npc (621217) | more than 4 years ago | (#30860090)

No. You have made a critical error in thinking. You need to think relativity wise. Scale changes how much power we need. As of yet we don't have many small things that need small amounts of power because we have NOT had the engine. Now that we have the small heat engine, it will allow us to develop small devices that use it.

Assuming we had micro engines, we can take full advantege of many things that are better smaller than bigger.

For example, a small device that turns heat into power could power an IMPLANTABLE MEDICAL DEVICE using the bodies own heating/cooling systems? No more changing the battery for the pacemaker every

Then there are small flying devices. I am sure the military would love a flying camera the size of a real fly that uses the solar heat of the sun to power it.

Then there are phones and musical devices. Want one that uses half of its' own waste heat to recharge itself, perhaps doubling battery life?

Re:Usefulness? (1)

Red Flayer (890720) | more than 4 years ago | (#30860372)

Then there are phones and musical devices. Want one that uses half of its' own waste heat to recharge itself, perhaps doubling battery life?

There's a reason we don't already use the waste heat for recharging electronics... because it's damn expensive. There are far better components for turning a heat gradient into electricity than this type of motor.

Looking at your other examples... the promise of this device is not in turning heat into electrical power. It's about turning heat into physical power. Think transport of tiny, tiny objects (microsurgery for vascular repair, for example).

Re:Usefulness? (2, Insightful)

Thelasko (1196535) | more than 4 years ago | (#30860778)

As an engineer that works with heat engines. I don't see what is so difficult about making a small heat engine. However, if one were to make a heat engine seven orders of magnitude smaller, with the same efficiency of a full sized heat engine... THAT would be an accomplishment!

Unfortunately, both the article and the summary have left out that detail...

Re:Usefulness? (1)

bluefoxlucid (723572) | more than 4 years ago | (#30861440)

Have you played Metroid Prime on the Gamecube? The first game, in Norfair, there's a geothermal power station with giant cylinders embedded in volcanic walls suspended just above the lava flow. They constantly pump. They're... HUGE.... I thought it was pretty epic, considering the larger engine would have a higher total efficiency; but I never figured out how the rock face would be cool enough to support high efficiencies (it's not molten, but it's still fucking hot). Just an interesting thought for you, since it seems to be in your field and I figure you might find the cultural reference (and the associated mind games trying to work out if/how this would work in real life) pleasant.

Heat engine != internal combustion engine (3, Insightful)

Dilligent (1616247) | more than 4 years ago | (#30859952)

Somehow "heat engine" directly translates into "internal combustion engine" for me. But this piece uses electricity, exactly how useful is that? This is bound to be less efficient than to use the electricity to just power an ordinary electric motor. I suppose scaling a motor down to that size might be kinda difficult, though, if that was the point, why emphasize that it is a heat engine?

Re:Heat engine != internal combustion engine (1, Informative)

Anonymous Coward | more than 4 years ago | (#30860150)

Because the researchers can't say spent their grants to make a piece of metal that vibrates a little more then the last piece of vibrating metal. By comparing this to one of the greatest and most useful inventions of all time and then saying they shrunk it 7 orders of magnitude really makes for a great press release, at least on /.

Re:Heat engine != internal combustion engine (5, Informative)

Scrameustache (459504) | more than 4 years ago | (#30860220)

Somehow "heat engine" directly translates into "internal combustion engine" for me.

That's too bad, I hope this article will be enough to let you correct your thought

why emphasize that it is a heat engine?

Because they figure it's mostly usefull as a heat pump, not as a mechanical actuator.

Re:Heat engine != internal combustion engine (4, Informative)

qazwart (261667) | more than 4 years ago | (#30860368)

The internal combustion engine is only one class of heat engines. The Sterling Engine and the External Combustion Engine (used in old steam locomotives) are also heat engines. Heat engines use heat to create power either by taking advantage of temperature differences or the expansion of heated air.

Re:Heat engine != internal combustion engine (0)

Anonymous Coward | more than 4 years ago | (#30860850)

A Stirling engine is an external combustion engine, as is a steam engine.

Re:Heat engine != internal combustion engine (1)

BlueKitties (1541613) | more than 4 years ago | (#30860420)

It's a conversion of thermal energy into mechanical motion. It may be far off, but this is something that could harness a very abundant but difficult to use energy source -- heat. I'm not sure how effective or efficient these could become, but it's still an interesting prospect.

Re:Heat engine != internal combustion engine (1, Funny)

Rogerborg (306625) | more than 4 years ago | (#30860514)

why emphasize that it is a heat engine?

Probably just trying to get some free publicity when California bans it.

Re:Heat engine != internal combustion engine (4, Informative)

mcgrew (92797) | more than 4 years ago | (#30860560)

Somehow "heat engine" directly translates into "internal combustion engine" for me.

A steam engine is an external combustion engine, yet is is still a heat engine. The thing with this teensy engine is that it reuses waste heat rather than throwing it away, making it far more efficient than your ordinary electric motor.

As a side note, the difference between a motor and an engine is that a motor rotates, an engine reciprocates. You can indeed have an electric engine (theyre usually called "solenoids") and a gasoline motor (Mazda had "rotary engines" back in the '70s; they were actually gasoline motors.)

Re:Heat engine != internal combustion engine (2, Informative)

YttriumOxide (837412) | more than 4 years ago | (#30860900)

Mazda had "rotary engines" back in the '70s; they were actually gasoline motors.

Had? Wouldn't "have had ... since [wikipedia.org] " be more accurate? (oh, and it's since 1963 [wikipedia.org] , so the '60s...)

Re:Heat engine != internal combustion engine (1)

Chris Burke (6130) | more than 4 years ago | (#30861282)

As a side note, the difference between a motor and an engine is that a motor rotates, an engine reciprocates.

Huh. I didn't know that.

So I guess that means that Wankel was being a bit of a Wanker when he named his Wankel Rotary Engine, huh?

Isn't this a... (1)

Anonymous Coward | more than 4 years ago | (#30859968)

Peltier diode?

SteamPunk nanobots! (1)

HeckRuler (1369601) | more than 4 years ago | (#30860052)

Finally my plan for steampunk (almost)nanobots can come to fruition! Those millions in grant money to the blacksmith have finally paid off.

They were damn lucky... (0)

Anonymous Coward | more than 4 years ago | (#30860122)

...with that UFO crash [odeo.com] in Holland two years ago.

More Entropy, that is exactly what need... (1)

jameskojiro (705701) | more than 4 years ago | (#30860140)

I guess the Logopolians will have to spend even more time doing base block calculations to prevent the heat death of the universe.....

I'm rather intrigued... (1)

91degrees (207121) | more than 4 years ago | (#30860144)

Apparently there are 0.001mm^2 engines already!

Reeedeeeculous (0, Troll)

Ancient_Hacker (751168) | more than 4 years ago | (#30860242)

Sometimes I despair about the level of scientific knowledge imparted to today's youth.

There is NO WAY to make a heat engine of any efficiency smaller than a few cc's.

It's the basic SCALING LAW that Galilleo figured out like 600 years ago.

As you make things smaller, their volume, which is their abilitry to burn fuel, goes down as the CUBE of its linear dimension.

But its surface area, which is how it loses heat, only goes down as the square.

So as you shrink things, pretty soon, you can't start a fire. The fire loses heat over its surface area faster than itrs volume can generate it.
Which is why you don't see flames smaller than a certain, much larger than micrometer, size.

Even for non-flame sources, the exact same rules apply. So you can't make a heat engine of any usable efficiency below a certain size. Model-airplane engines of 1cc capacity are about the lower practical limit. Anything smaller and you have trouble getting it to light off and even if it does, the heat quickly dissipates.

So just on general principles, one can guess that this touted device has vanishingly small efficiency.

And no, no "but we can INSULATE it" or "the RULES are DIFFERENT down there".

Re:Reeedeeeculous (2, Informative)

Guppy (12314) | more than 4 years ago | (#30860436)

So as you shrink things, pretty soon, you can't start a fire. The fire loses heat over its surface area faster than itrs volume can generate it.
Which is why you don't see flames smaller than a certain, much larger than micrometer, size.

So if I'm understanding this argument correctly, the limitation can also be understood in terms of the time window available in which to extract the energy decreases, as the engine scales down. At a material level, the heat dissipation has a limit as well -- for conduction, it can't be any faster than the speed of sound (within the material comprising the engine).

While we don't have any information on the frequency at which the piezo engine operates, it could be very high, allowing for nearly instant energy extraction. We could possibly be approaching the limit at which the two limitations compete.

Re:Reeedeeeculous (5, Insightful)

ThreeGigs (239452) | more than 4 years ago | (#30860442)

And I despair of the lack of English education, specifically reading comprehension.

This isn't internal combustion, which is what your argument is based on. It uses the fact that solids expand and contract when heated and cooled, including some piezo materials.

Please read the summary *again*.

Re:Reeedeeeculous (1)

El Gigante de Justic (994299) | more than 4 years ago | (#30861232)

To be fair, its a poorly written summary that can easily cause anyone who doesn't have a background in this area of engineering to assume it's only talking about internal combustion engines because of the first two to three sentence:

"The vast majority of motors that power our planes, trains, and automobiles are heat engines. They rely on the rapid expansion of gas as it heats up to generate movement. But attempts to shrink them by any significant amount have mostly ended in failure."

This could be interpreted by many as "Heat engines, like those we use to power vehicles, rely on the rapid expansion of gas as it heats to generate movement, and engineers have been unable to shrink them by any significant amount". The summary could have been much clearer by defining a heat engine has any device that converts heat to mechanical work, and stated that internal combustion engines are one type of heat engine, but there are other types as well.
    Even when I first read it, I was thinking "How'd they even get an internal combustion engine down to 10^7 cubic micrometers?". It would have been helpful if it described that heat engine as well, since it's obviously not internal combustion.

Re:Reeedeeeculous (4, Insightful)

sunking2 (521698) | more than 4 years ago | (#30860446)

It's almost as pathetic as the idiots who assume heat engine == combustion engine.

Re:Reeedeeeculous (4, Insightful)

kgskgs (938843) | more than 4 years ago | (#30860902)

What has happened to Slashdot? Who do you have to be a Guru in every subject to read Slashdot?

Looks like gone are the days when all you needed to good discussions on Slashdot was genuine curiosity and decent , not necessarily perfect, grasp of English language. And no, being a know-all, done-all master of the universe was not required either.

While I can perfectly understand saying "You are making a mistake" or "That's not what the article says", I have never really understood calling someone pathetic for not knowing something.

The range of topics covered here is very wide and I don't know abc of several things discussed here. Does that make me stupid and pathetic?

Re:Reeedeeeculous (5, Insightful)

AaxelB (1034884) | more than 4 years ago | (#30861336)

The range of topics covered here is very wide and I don't know abc of several things discussed here. Does that make me stupid and pathetic?

The key point is that you recognize that you don't know everything about the topic at hand. The post that sunking2 was responding to was essentially a spew of vitriol against the researchers, claiming that it's impossible to make such a small engine with any sort of efficiency, and that they're stupid and ignorant for even trying. According to that post's replies, the writer is completely wrong and doesn't know some basic facts about the subject they're yelling about.

So, no, you're not at all stupid and pathetic for not knowing everything about everything, and I'm in the same boat with you (I've learned a fair amount from this story's discussion), but neither of us is telling everyone (including the Dutch engineers in question) that they're stupid and don't know what they're talking about.

Re:Reeedeeeculous (0)

Anonymous Coward | more than 4 years ago | (#30860966)

It's almost as pathetic as the idiots who assume heat engine == combustion engine.

Is that supposed to be common knowledge?

Re:Reeedeeeculous (1)

witch-doktor (1592325) | more than 4 years ago | (#30860480)

This reference may be relevant: http://www.ingentaconnect.com/content/tandf/umte/1998/00000002/00000002/art00006?crawler=true [ingentaconnect.com] "...Results from this study show that a small-scale heat engine fabricated from a low-thermal-conductivity material can be made with a length scale approaching 1 mm. Such a device would undoubtedly be composed of numerous microscale components. Below the 1-mm limit, efficiency suffers to such a degree that solid-state thermoelectric devices would become a better choice for a particular application. "

Re:Reeedeeeculous (0)

Anonymous Coward | more than 4 years ago | (#30860524)

not a word about any fire in TFA, it rather talks about heat from electrical resistance - so the engine is electrical, but not electro-magnetic - it's rather an electro-piezo-heat-engine

stress: no combustion, but piezo-effects and electro-resistance

Re:Reeedeeeculous (0)

Anonymous Coward | more than 4 years ago | (#30860562)

Heat engines do not require that they burn any fuel, they all operate by converting heat to some other form of energy. You are correct in thinking that an internal combustion will have lousy efficency at that size, but it is not true for all heat engines, their power output is mostly dependent on the difference in tempreture of the two sides and thus how much energy they can move per unit area. A very small heat engine can be used to create a paper thin wall that extracts energy and from the temp differential, the fuel can be a flame against a steel plate with millions of mini heat engines on the other side.

However this type of heat engine is probably most useful as a chip cooler which would allow heat to be moved around to cooler spots on the chip, if we want efficient we can do that, an engine using the carnot cycle can hit the maxium possible efficency and can be made to exceed 70% efficency in the real world, but they are expensive and big (and thus not useful for cars).

Re:Reeedeeeculous (4, Insightful)

SoVeryTired (967875) | more than 4 years ago | (#30860606)

It's the basic SCALING LAW that Galilleo figured out like 600 years ago.

As you make things smaller, their volume, which is their abilitry to burn fuel, goes down as the CUBE of its linear dimension.

But its surface area, which is how it loses heat, only goes down as the square.

That'd be Newton's law of cooling, no more than 300 years old.

Re:Reeedeeeculous (1)

JoeMerchant (803320) | more than 4 years ago | (#30860712)

I doubt they're trying to oxidize fuel in that volume - more likely they are transferring heat from one volume of gas to another.

Re:Reeedeeeculous (1)

jo_ham (604554) | more than 4 years ago | (#30860714)

How did this get +3 informative?

How about -1 "did not read the summary and assumed it was an IC engine".

Re:Reeedeeeculous (1)

cynyr (703126) | more than 4 years ago | (#30861034)

heat engine != ICE... no fire needed.

Re:Reeedeeeculous (1)

ravenshrike (808508) | more than 4 years ago | (#30861252)

What does Immigration and Customs Enforcement have to do with piezoelectric heat engines?

Peltier elements? (0)

Anonymous Coward | more than 4 years ago | (#30860308)

Surely thermoelectric semi-conductors would do the trick?

They may not be very efficient, but I'd suspect you could make them fairly small if you utilized modern chip technology.

yea but (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30860448)

Cans dAy rUNz Da liNuX?!?! 0_o

Help Me (1)

SnarfQuest (469614) | more than 4 years ago | (#30860510)

The total volume of the device is just 0.5 cubic micrometres.

I know I parked my car around here somewhere. Anyone see it?

0.5 cubic micrometres?! (2, Insightful)

Phizzle (1109923) | more than 4 years ago | (#30860528)

So thats like much smaller than a womp rat!

2 wows (1)

happyjack27 (1219574) | more than 4 years ago | (#30860852)

when i saw the title i said "wow". then i read the summary, and i said "wow" again. that makes it a double-wow.

In Soviet Russia (1)

bdwebb (985489) | more than 4 years ago | (#30861030)

In Soviet Russia, engine...does not heat you. :(

I am 8.45^10 nanometers tall! (1)

nloop (665733) | more than 4 years ago | (#30861292)

Not only is 10 million much easier to understand than 10^7, but 0.01 cubic millimeters is a MUCH more common number, and measurement.

Not exactly hidden information either.

Nanites are in luck (1)

gsgriffin (1195771) | more than 4 years ago | (#30861354)

Now they don't have to peddle to work each day. The nanites can make a cool ride with one of these motors.

Re:Nanites are in luck (0)

Anonymous Coward | more than 4 years ago | (#30861408)

Way too big for nanites 0.5 cubic micrometres is 5*10^8 cubic nanometres.

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