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Pumping Fluid With No Moving Parts

timothy posted more than 3 years ago | from the all-sounds-very-zen dept.

Technology 75

RogerRoast writes "In a study published in Physical Review B (abstract; full version is paywalled), researchers demonstrate for the first time an approach that allows ferrofluids to be pumped by magnetic fields alone. The invention could lead to new applications for this mysterious material. Though numerous industrial, commercial, and biomedical applications for ferrofluids have since been created, the original goal — to pump liquids with no machinery — remained elusive, until now. The ferrohydrodynamic pump method works when electrodes wound around a pipe force magnetic nanoparticles within the ferrofluids to rotate at varying speeds. Those particles closest to the electrodes spin faster, and it is this spatial variation in rotation speed that propels the ferrofluid forward."

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An evolution from magnetohydrodynamics... (3, Informative)

BWJones (18351) | more than 3 years ago | (#37427404)

Magnetohydrodynamics [wikipedia.org] has been around for quite a while and has long been one of the holy grails of submarine propulsion with prototypes existing now for years. During my last visit to a Los Angeles class submarine [utah.edu] , this was a hot topic. Movement of ferrofluids is a natural extension of this concept with applications in everything from medical imaging to cooling of large and small objects. Its pretty exciting, though I am surprised that this is the *first* implementation of this.

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427426)

So those rotating nanoparticles are not moving parts?

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427444)

When you want to move a fluid, you at least need the fluid itself to be a moving part !

Re:An evolution from magnetohydrodynamics... (1)

Anonymous Coward | more than 3 years ago | (#37427438)

Wouldn't this require spiral ridges to create directed motion?

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427446)

Its odd. I was just researching MHGs since I had a unique idea on it. I will have to see if they did something similar. Hopefully, not.

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427650)

How about you tell us your idea and we'll let you know. Make sure to post anonymously so nobody will sue you.

Re:An evolution from magnetohydrodynamics... (5, Funny)

Rosco P. Coltrane (209368) | more than 3 years ago | (#37427460)

Magnetohydrodynamics has been around for quite a while and has long been one of the holy grails of submarine propulsion with prototypes existing now for years.

Pfft, soviet submarines have had MHD drives since 1984. I saw a documentary about it in 1990...

Re:An evolution from magnetohydrodynamics... (3, Funny)

evanism (600676) | more than 3 years ago | (#37427498)

Hunt for Red October wasn't a documentary :)

Re:An evolution from magnetohydrodynamics... (1)

Anonymous Coward | more than 3 years ago | (#37427514)

Pffft... Captain Nemo used it hundred and fifty years ago for his submarine already.

Re:An evolution from magnetohydrodynamics... (-1)

Anonymous Coward | more than 3 years ago | (#37427558)

wooooooshh

Re:An evolution from magnetohydrodynamics... (1)

Sulphur (1548251) | more than 3 years ago | (#37427700)

Hunt for Red October wasn't a documentary :)

Was it Sean Connery or Sam Neal that gave it away?

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427720)

Hunt for Red October wasn't a documentary :)

Was it Sean Connery or Sam Neal that gave it away?

Can we stop blaming the whistleblowers already?

Re:An evolution from magnetohydrodynamics... (3, Funny)

grumling (94709) | more than 3 years ago | (#37428548)

You mean Russians don't have Scottish accents?

I bet you think Spaniards don't have Scottish accents either.

Re:An evolution from magnetohydrodynamics... (1)

Shadow of Eternity (795165) | more than 3 years ago | (#37431430)

He wasn't spanish, he was an egyptian pretending to be a spaniard with a scottish accent. Also known as not even trying.

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37431554)

He wasn't spanish, he was an egyptian pretending to be a spaniard with a scottish accent. Also known as not even trying.

He should have known better: You can be only one.

Re:An evolution from magnetohydrodynamics... (3, Interesting)

Wonko the Sane (25252) | more than 3 years ago | (#37428284)

If you go by the book the Red October didn't use MHD, it had a propulsor that was mounted in the middle of a tube that ran the length of the ship so the noise was more difficult to detect.

Somebody had probably been talking to Clancy about the ducted propulsor that is used on the Seawolf class submarines and he changed a few details (like putting it inside the hull instead of on the back end of the ship) and used it as a plot point.

Re:An evolution from magnetohydrodynamics... (1)

EdZ (755139) | more than 3 years ago | (#37427654)

Unfortunately, MHD is pretty rubbish for submarines due to the existence of the Magnetic Anomaly Detector. That, and at usefully high power levels water starts to break down between the electrodes, creating noisy arcing and bubbles.

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37427724)

They explained the arcing and bubbles in the documentary—it sounds like whales humping.

Re:An evolution from magnetohydrodynamics... (2)

interval1066 (668936) | more than 3 years ago | (#37427770)

Yeah, my dad worked in cold-war intelligence (mostly Soviet satellite analysis) and I asked him about this a few years back. We talked at length about Soviet "alternate technology" including their ambitious psychic ability research. I asked him why we didn't have MHD subs. His comment was even though the Soviets spent BILLIONS (with a 'B') on these programs that most of that effort was worth about as much as a deed to the Brooklyn Bridge.

Re:An evolution from magnetohydrodynamics... (1)

Doc Ruby (173196) | more than 3 years ago | (#37430602)

So? The US spent $BILLIONS on all kinds of tech in the Cold War that was a worthless scam, too. Star Wars / SDI is the most obvious, but there's many weapons systems in that list. In fact the US probably spent more, since we spent so much more overall on the Cold War. The Russians, with their non-convertible currency and forced labor, were more likely to kill R&D by cheaping out than the US was.

Re:An evolution from magnetohydrodynamics... (1)

interval1066 (668936) | more than 3 years ago | (#37430690)

So? I'm an American, and my comment was on point. What's YOUR point?

Re:An evolution from magnetohydrodynamics... (1)

catmistake (814204) | more than 3 years ago | (#37431004)

So? The US spent $BILLIONS on all kinds of tech in the Cold War that was a worthless scam, too. Star Wars / SDI is the most obvious

Actually, SDI was one of the most successful missions in the history of cloak and dagger stuff... apparently, it was a cover for a mass assassination mission. [wikipedia.org] 25 scientists working on SDI met mysterious end [explained.at]

Re:An evolution from magnetohydrodynamics... (1)

rossdee (243626) | more than 3 years ago | (#37427764)

I presume the high magnetic field is what alerted the (ASW variant) Bear to their presence just before they entered the trench. Anyway my main criticism of the 'caterpillar"drive is the fact tht the watertubes would pass right through the center of the boat, there wouldnt be room for the vertical missile tubes which after all is the raison d'etre of an SLBN

Re:An evolution from magnetohydrodynamics... (2)

arisvega (1414195) | more than 3 years ago | (#37428386)

MHD is pretty rubbish for submarines

You mean it is pretty rubbish for military operations, because it may be noisy. Otherwise, I believe, it is pretty damn cool.

jesus (0, Flamebait)

Anonymous Coward | more than 3 years ago | (#37427800)

"Magnetohydrodynamics [wikipedia.org] has been around for quite a while"

Wow, you mean, like, REALLY? An entire field of applied maths/physics has been around "for quite a while"? I must run and tell the solar physicists!!!!!!!!!

"Magnetohydrodynamics... has long been one of the holy grails of submarine propulsion with prototypes existing now for years."

This is non-sensical and you know it. Magnetohydrodynamics is a theory. It is not submarine propulsion, which is the business of making submarines move. If you can't tell the difference between these you may as well give up and fuck off.

"During my last visit to a Los Angeles class submarine [utah.edu], this was a hot topic"

Oh man, I'm sorry, I didn't realise you were so important! Let me lick your boots.

Re:jesus (0)

Anonymous Coward | more than 3 years ago | (#37427872)

:(

I offered to lick his boots! That doesn't deserve a -1 :'(

Re:An evolution from magnetohydrodynamics... (0)

Anonymous Coward | more than 3 years ago | (#37428222)

Yup. There is a ship on display in Kobe, the Yamato, which was built to test this. Very slow top speed of 7 knots if I am not mistaken. Also requires a lot of power and superconducting magnets.

Re:An evolution from magnetohydrodynamics... (1)

Walt Dismal (534799) | more than 3 years ago | (#37428266)

Decades ago I discovered as a student (accidently in a chem lab) that you can pump dielectric and polar fluids without moving parts using a porous filter material (like ceramic) and a high voltage applied to the top and bottom surface. The flow rate is slow but it too requires no moving parts. Only modest current is needed at 800-900 volts.

By using a shaped container around the filter to operate as a hydraulic lever, I imagine you could achieve higher flow rate in a narrow diameter tube, which might work for some applications like small actuators.

I didn't patent it.

Re:An evolution from magnetohydrodynamics... (1)

bar-agent (698856) | more than 3 years ago | (#37429912)

Decades ago I discovered as a student (accidently in a chem lab) that you can pump dielectric and polar fluids without moving parts... I didn't patent it.

Why-ever not? Maybe this is a well-known phenomena among chemists, but I've never heard of it before.

Hm. Maybe I'll stop by the PTO later today and rectify this oversight...

Re:An evolution from magnetohydrodynamics... (1)

Doc Ruby (173196) | more than 3 years ago | (#37430624)

If you do patent it, I hope Walt Dismal later takes all the money you make from it. I'll be happy to show the PTO the link to this subthread.

Or, since you're interested, you could just replicate it and commercialize it, without hiding behind a government monopoly granted to someone else's work.

Re:An evolution from magnetohydrodynamics... (-1)

Anonymous Coward | more than 3 years ago | (#37428546)

If I wanted to pump saltwater without moving parts, I'd try two metal meshes spaced apart in a "jet" (cylindrical tube). With a high potential between the meshes, the water should be pulled from one to the other (same metal type, to avoid some corrosion).

If corrosion ended up being too big a problem, then place a metal mesh insulated in a jet tube, and use the body of the jet tube ahead of or behind the mesh and pass a voltage between those. This might put the corrosion in a better place, if the body of the ship is setup as the anode and there is a different type of metal for the mesh. It might be possible to intentionally create a battery out of the ship's hull this way (scale up the mesh too), using the ocean as an electrolyte, and have a non-nuclear sub capable of electric propulsion without any moving parts. I recommend calling it the bat sub, just because. If batman had a sub, that'd be it.

Failing that, build a vessel that glides along the bottom of the ocean, instead of a variable depth. Use the seafloor as an earth ground, and push against it using an electric current. The downside would be traditional propulsion is necessary over rough seafloor, when surfaced, or at too shallow a depth.

It might also be possible to propel the underwater craft using HVDC (or perhaps a low frequency AC) being supplied on land. Passing the voltage through the ocean and using the ship as a superior conductor, propelling it. I bet it'd be nicknamed the Long Rope, or something like that. Same basic principal, except an electric current replaces a literal rope.

If electricity isn't your preferred medium, it should be possible to build a thermal drive. An airfoil that's heated on one side should work underwater for forward propulsion, depending on the ships buoyancy. The thermal drive could be powered by a typical nuclear reactor or simply alpha decay (use a specially designed RTG to generate electricity and propulsion). The ship's hull doesn't necessarily need to be heated (to avoid thermal expansion/contraction noises), and the airfoil could be a mesh with specially sized holes instead of solid material, and it could lead the ship unlike traditional airplane wings needing to be on the sides. In fact, a flat plate could function as an airfoil (even on an actual airplane) if it has varying sized holes and/or dimples across it's surface, in the right pattern. In fact, with an elaborate enough design, there'd be no equivalent of a cross wind as with a traditional airfoil.

I'm sure half of what I've said is wrong or arguably insane. My point is, this technology should already exist. It's not an unimaginable feat and any research into this would only fail outright if given a bad deadline or other fake bureaucratic hurdles. Even a fictional character like Mr. Bean could pull this off if given enough time and an adequate movie budget, perhaps. Shoot, I think this might all be offtopic for this thread, and I might actually be either an idiot, insane or both. *DOH*

Re:An evolution from magnetohydrodynamics... (1)

Kagura (843695) | more than 3 years ago | (#37431596)

Nice article, thanks for writing it! I only wish I could take part in a visit like that.

I don't know (5, Funny)

evanism (600676) | more than 3 years ago | (#37427496)

When I want to pump my fluids, I like to have my parts moving, nano or not!

Re:I don't know (-1)

Anonymous Coward | more than 3 years ago | (#37427858)

In your case it's more like atto, maybe femto on a good day. That's what my momma told me.

Lousily redacted contribution (0)

Anonymous Coward | more than 3 years ago | (#37427502)

RTFP! Read only the abstract and it seems that what the authors claim is _not_ that this is the first time movement of a ferrofluid is achieved using only magnets (btw, About 10 years ago i saw a demonstration of blood being circulated using magnetic field gradients) but most likely that they achieve it without the need of using _strong_ permanent magnets!

Cooling? (1)

Max Romantschuk (132276) | more than 3 years ago | (#37427534)

So if the ferrofluid is stable, this could be a closed loop, no moving parts, almost infinitely reliable cooling system?

Re:Cooling? (1)

julesh (229690) | more than 3 years ago | (#37427610)

Yes, although both the thermal capacity and conductivity of ferrofluids are lower than the equivalents for water. so you'd need to pump it somewhat faster than you would a water cooling system, but it could be a completely hermetically sealed unit, which has obvious advantages...

Re:Cooling? (1)

Doc Ruby (173196) | more than 3 years ago | (#37430650)

What's wrong with a rubber tube filled with fluid that's pinched between a flat wall and a rotating ovoid? The ovoid would roll against the tube, flattening it against the wall starting at one end of the tube segment within reach, pushing down along the length. That's a "hermetically sealed unit" that pumps fluid through the tube.

Re:Cooling? (1)

badkarmadayaccount (1346167) | about 3 years ago | (#37465652)

You just reinvented the artificial heart.

Re:Cooling? (2)

TeknoHog (164938) | more than 3 years ago | (#37427746)

So if the ferrofluid is stable

That's what I'm wondering too. It is a heterogeneous mixture where the magnets are solid particles, and a surfactant is needed to keep these particles from clogging together. I've dabbled in making some in a chemistry lab, and it was rather tricky getting the result right. There are the issues of both chemical and mechanical stability. Maintaining a constant flow should help with the clogging problem, but even then, there may be spots of low velocity and high pressure where particles start to concentrate.

Guinness rubbing their hands with glee (1)

Mike Mentalist (544984) | more than 3 years ago | (#37427560)

As if the hype about pouring the perfect pint of Guinness isn't already bad enough we now have to listen to them talk about cleaning the magnets as well as the pipes.

Nice. I wonder tho... (1)

MikShapi (681808) | more than 3 years ago | (#37427616)

If you can do it simply with air [inventgeek.com] can you do it with liquids?

Blood Pumps? (0)

Anonymous Coward | more than 3 years ago | (#37427640)

This would be great for blood pumping systems since even the slightest clot in those almost always lead to death.
This is one of the huge risks with artificial circulation systems, be it hearts, that huge bulky machine that acts as a lung too (CPBs), or those ventricular helpers.

Mind you, I believe centrifugal pumps have eliminated the pump problem and it is mostly a problem of clumps forming on the material walls, fibrin is hoping to fix this problem if I remember correct.

Plus, it depends how big it is and how much power it needs.
Size is always the important part.

Pumping fluid without moving parts is old news (1)

Anonymous Coward | more than 3 years ago | (#37427666)

Fluidyne engines [wikipedia.org] exist for quite a while now, don't require mysterious materials and no one seems to care.

UFOs (0)

Anonymous Coward | more than 3 years ago | (#37427678)

UFO drives work on Superconductor Ferrofluids ( so called Bose Einstein condensate) made from mercury - thallium alloy with magnetite.
The superconductor Ferrofluid is rotated at 60krpm in a donut . The rotating Superconductor seems to create the gravitons if they exist.

http://www.youtube.com/watch?v=pJJ-4lnwrck
http://www.nature.com/nature/journal/v448/n7154/abs/nature06036.html
http://vimeo.com/28098847
http://www.disclose.tv/action/viewvideo/34265/Fun_with_ferrofluid/

Interesting to see a macro-scale solution (2)

manicb (1633645) | more than 3 years ago | (#37427690)

This is a popular problem in microfluidics. For lab-on-a-chip technology it is very difficult to make a pump with moving parts on the micrometre scale, so researchers have turned to more obscure phenomena. Electro-osmosis [wikimedia.org] is commonly used. Essentially, in a channel with dielectric walls, a very thin ionic double layer naturally forms at the solid-liquid interface. If an electric field is applied in the direction of travel, this drags the thin ionic layer, which in turn mobilises the bulk liquid.

Researchers have been playing with magnetic nano-particles in microfluidic systems for years, usually in the context of a separation system. This spinning phenomena is interesting, and could well be used for more than just pumping. In narrow enough channels, if there is only a moderate concentration of these particles then I doubt they would be close enough together to act as described here.

It's a shame the paywall makes it hard for most of us to really RTFA. I'll report back if there's anything interesting...

Re:Interesting to see a macro-scale solution (4, Informative)

manicb (1633645) | more than 3 years ago | (#37427734)

(Sorry for gloating, I *finally* got access to journals again and it is SO EXCITING. I have no life.)

Right, according to the article, the reason people have looked at ferrofluids for microfluidics is that they were interested in using a thin layer of ferrofluid to drive a plug of other liquid. This would be analogous to the ionic double-layer (Debye layer) in electro-osmosis, as mentioned above. In this experiment, they use only ferrofluid (with a dash of a tracer) and seem to achieve a funky toroidal region, leading to ordinary laminar flow. If they excited it in more places then they could have a lot of mixing, which would be great for a cooling system.

Re:Interesting to see a macro-scale solution (0)

Anonymous Coward | more than 3 years ago | (#37428184)

(Sorry for gloating, I *finally* got access to journals again and it is SO EXCITING. I have no life.)

Right, according to the article, the reason people have looked at ferrofluids for microfluidics is that they were interested in using a thin layer of ferrofluid to drive a plug of other liquid. This would be analogous to the ionic double-layer (Debye layer) in electro-osmosis, as mentioned above. In this experiment, they use only ferrofluid (with a dash of a tracer) and seem to achieve a funky toroidal region, leading to ordinary laminar flow. If they excited it in more places then they could have a lot of mixing, which would be great for a cooling system.

Isn't this how they think that "Alien" space craft are able to defy gravity? They have some sort of fluid that spins creating some sort of anti-gravity thus the reason there always disks!

Re:Interesting to see a macro-scale solution (0)

Anonymous Coward | more than 3 years ago | (#37428260)

I'd like to see a UFO shaped like a diskette.
That'd be neat.

Re:Interesting to see a macro-scale solution (1)

sgt scrub (869860) | more than 3 years ago | (#37428318)

It would be a big floppy.

Albert Einstein's life-saving refrigerator (1)

Anonymous Coward | more than 3 years ago | (#37427752)

Albert Einstein and a colleague of his were grief-stricken when they heard about an entire family that was killed when the Ammonia gas leaked out of their refrigerator.

Refrigerant fluid needs to be pumped, so there is a seal around the shaft from the electric motor to the pump mechanism. Seals blow all the time - if your car leaks oil, the chances are pretty good it's a leaky seal. A blown seal on a car will drip oil, maybe ruin your engine, but if you blow the seal that's holding in a bunch of compressed Ammonia gas and you can't get outside to fresh air quickly enough, you'll die horribly. I imagine it was just like being in a World War I gas attack.

At the time Freon had not yet been developed, so the only effective refrigerator coolant available was Ammonia, NH3. The Ammonium Hydroxide floor cleaner is NH3Oh, basically Ammonia gas dissolved in water, and smells pungently of the Ammonia gas evaporating from the solution, but not so much as to be toxic.

Einstein and his colleague decided to use the basic laws of thermodynamics to design a refrigerator that would have no moving parts at all. Thus it could be a sealed system, most likely out of copper or brass pipes soldered together. There would be some chance of leaking through the solder joints, but they can be adequately pressure-tested during manufacture, and are not so likely to wear out as mechanical seals.

I've seen it on The Series of Tubes before, let me find you a link... Einstein's green refrigerator making a comeback [physorg.com] . Besides Ammonia it also uses Butane and Water. You apply heat to one part of the assembly, and another part gets cold. The article points out that the heat source could be the Sun; a cylindrical or parabolic mirror on the roof of your house could supply the heat, so it would use no electricity at all!

Einstein's collaborator was his former student Leo Szilard. Szilard also invented the fission bomb. Einstein is widely credited with writing the letter to President Roosevelt that convinced the President to initiate the Manhattan Project, but that letter was actually written by Szilard. Szilard just asked Einstein to sign it because Szilard, at the time, was young and largely unknown, while Einstein was one of the most famous people on the planet. Presidents know to open that kind of junk mail!

Re:Albert Einstein's life-saving refrigerator (2)

jbengt (874751) | more than 3 years ago | (#37428836)

Refrigerant fluid needs to be pumped, so there is a seal around the shaft from the electric motor to the pump mechanism.

There does not need to be a shaft seal. Almost all modern small to medium sized mechanical refrigeration compressors are hermetic or semi-hermetic; that is, the motor, drive, and shaft are all contained inside the system along with the refrigerant.

Though there is no explanation of how it works at the link you provided, "Einstein's green refrigerator" seems to be an absorption refrigeration cycle, which was well known at the time, having been around since the mid-1800's. (According to Wikipedia "In 1922 Baltzar von Platen and Carl Munters . . . enhanced the principle with a 3 fluids configuration. This "Platen-Munters" design can operate without a pump." and "In 1926 Albert Einstein and his former student Leó Szilárd proposed an alternative design known as Einstein refrigerator".) Mechanical pumps are usually used in absorption refrigeration, this design "pumps" the fluid using the differences in vapor pressure and density, relying on boiling, condensing, and the force of gravity. The fact that it does not have any mechanical pumps or moving parts, but relies on gravity, probably means it would be impractically tall and/or very inefficient.

Since butane is a Class A3 refrigerant (very flammable) and ammonia is Class B2 (toxic and flammable) it is doubtful that this system would be used in residential settings. It used to be common to use ammonia, butane, or sulfur dioxide in refrigerators, but there were many tragedies like the one described. Ammonia is still very common in industrial refrigeration systems where safety can be monitored and controlled, and butane, and even sulfur dioxide, have their niches. But ammonia systems are no longer sold for residential use, even in sealed systems, for a variety of reasons.

More here. [google.com]

Re:Albert Einstein's life-saving refrigerator (2)

manicb (1633645) | more than 3 years ago | (#37429670)

Refrigerant fluid needs to be pumped, so there is a seal around the shaft from the electric motor to the pump mechanism.

There does not need to be a shaft seal. Almost all modern small to medium sized mechanical refrigeration compressors are hermetic or semi-hermetic; that is, the motor, drive, and shaft are all contained inside the system along with the refrigerant.

Other options used widely in industrial and laboratory equipment include peristaltic and membrane pumps where the mechanism is separated from the liquid by a flexible barrier. Magnetically coupled pumps of various designs also exist.

Mmm, roboturgor (1)

Anonymous Coward | more than 3 years ago | (#37427786)

Turgor - fluid pressure in compartments - is one of the ways critters and plants move. Pumps + ferrofluid + cells + control systems = some really bitchin' squishbots.

mod *down (-1)

Anonymous Coward | more than 3 years ago | (#37427832)

Pumping without moving parts is not news. (2, Informative)

Anonymous Coward | more than 3 years ago | (#37427942)

Pumping without moving parts is not news. Liquid metal cooled nuclear reactors, aluminium foundries use this technology, among other things.
Not rocket science, you can go buy yourself a magnetic metal "pump" today: http://www.cminovacast.com/prod/index.html (google 1st for liquid metal cooling pump).

Oh, you talk about magnetically pumping non-metals. Well that's nice.

parts is parts (1)

JimDR (1944842) | more than 3 years ago | (#37428044)

So, it is a whole bunch of moving parts.

Magnetohydrodynamic pumps (1)

zzyzyx (1382375) | more than 3 years ago | (#37428238)

Magnetohydrodynamic pumps that can move a liquid without moving parts have existed for a long time and for example are used to pump liquid sodium in some nuclear reactors. Any conductive liquid can be pumped that way.

So it's wrong to say that the "goal to pump liquids with no machinery remained elusive, until now". What's new is the ability to pump a magnetic fluid using only a magnetic field.

nikola tesla strikes again (0)

Anonymous Coward | more than 3 years ago | (#37428300)

http://en.wikipedia.org/wiki/Tesla_turbine

induction pump (0)

Anonymous Coward | more than 3 years ago | (#37428330)

Such pumps art part of wave soldering devices for 30 years now...

No it isn't the first application (1)

Anonymous Coward | more than 3 years ago | (#37428494)

Liquid metals are used for cooling nuclear power plants and electromagnetic pumps have been around for a long time. You can pump any conductive liquid. I've built them myself for a prototype of a heat exchanger my company refused to patent. Not their core business and heat exchangers are "a commodity". Look how much DARPA puts into heat exchangers. Dumb.

For a test system machine some slots that you can pound thick, insulated wires into parallel to each other in a triangle, hexagon, etc shape in a block of non-conductive material (you can use aluminum, just be careful) so that after you pound in the wires into the slots you can machine a triangle shape fluid path with exits at each point of the triangle so that sides of the wire are bare to the fluid channels. Put clear tubes into the fluid exit channels and run those into colored water.

Wire the ends of the thick wires to a board. Changing polarity changes fluid directional flow. Getting the voltage right was a challenge and I don't remember what I used, but, I remember it was higher than I thought it should be.

By changing the polarity and voltage applied to one set of the wires you can change the direction of fluid flow.

Imagine a heat exchanger like this on a board. As different areas of the board heat up the fluid flow changes applying more cooling to the area that is hottest. Pretty kewl stuff, solid state.

No moving parts? (1)

mwvdlee (775178) | more than 3 years ago | (#37428846)

Aren't the electrons moving?

Re:No moving parts? (0)

Anonymous Coward | more than 3 years ago | (#37429384)

Nope. The electrons are held in place with teeny tiny zip-ties.

HS Science fair project anyone? (0)

Anonymous Coward | more than 3 years ago | (#37428858)

I 1966 I personally saw a similar pump in action at my high school science fair. It was made from an old transformer and plastic tubing. I don't even think it won any awards. The fluid wasn't fancy, just salt water. I seem to recall the presentation mentioned the potential it coule used as a propulsion system for submarines.

Of course, I didn't read TFA but I'm curious what mysterious properties were "demonstrated for the first time" when as HS student (and his dad) built a working pump more than 40 years ago.

Re:HS Science fair project anyone? (0)

Anonymous Coward | more than 3 years ago | (#37429028)

I believe the project you saw was based on an article in Popular Science, Jan 1966, page 112. It can be read on Google books:

http://books.google.com/books?id=mikDAAAAMBAJ&printsec=frontcover&dq=%22popular+science%22+%22chesapeake+bay+bridge+tunnel%22#v=onepage&q&f=false

Re:HS Science fair project anyone? (1)

nschubach (922175) | more than 3 years ago | (#37429536)

Man, I thought PS had a lot of ads in the 80s... this is insane.

wow (1, Insightful)

Osgeld (1900440) | more than 3 years ago | (#37429062)

moving magnetic material with a magnet ... next up the no shit hour

How is this news? (2)

LynnwoodRooster (966895) | more than 3 years ago | (#37429214)

Anyone who's worked in audio speaker design and used ferrofluid (a common addition to tweeters and small, wide-band drivers, but sometimes used in larger drivers) knows that it will migrate (flow) with the magnetic field applied by the voice coil... In fact, careful attention must be paid to the ratio of voice coil field to static field and the shape of the magnetic gap to keep the ferrofluid from not blowing out of the gap.

Use it for touchscreens (2)

sonamchauhan (587356) | more than 3 years ago | (#37429776)

Ferrofluid touch interface
Touch interface that uses Ferrofluids to provides tactile feedback
http://www.halfbakery.com/idea/Ferrofluid_20touch_20interface [halfbakery.com]

Dammit (0)

Anonymous Coward | more than 3 years ago | (#37430010)

I guess halfbakery no longer constitutes as "prior art" since we've gone from first to invent to first to file. That place is probably being scoured right now...

Troll Science (1)

localtoast (611553) | more than 3 years ago | (#37430490)

brotip: Use magnetz for faster fluid. http://trollscience.com/ [trollscience.com]

Ferrofluid Vapor Pressure? (1)

Doc Ruby (173196) | more than 3 years ago | (#37430544)

Is there a way to evaporate these ferrofluids? Then sunlight could evaporate some ferrofluid against gravity, leaving it to condense and drain back through these "pumping" channels. By letting the moving fluid drive electrons through the pump's power circuits, the way an electric motor becomes a generator when a moving medium turns its driveshaft (eg. a windmill), the fluid would generate electrical power. Solar power might be captured at very high efficiency, in machines requiring very little/infrequent maintenance. Their overall efficiency would thereby increase, and make them more installable in places hard to reach but close to sunlight.

The sunlight might have to be concentrated if the evaporation point is hard to reach. But as long as the concentrated light vaporizes it without burning or otherwise chemically changing the ferrofluid, this kind of system could work. Combining high efficiency with large energy scales would mean lots of efficient energy.

Re:Ferrofluid Vapor Pressure? (1)

jeffb (2.718) (1189693) | more than 3 years ago | (#37434024)

No, sorry. Ferrofluids are suspensions of nanoparticles, specially treated to keep them from clumping. Evaporate them, and you get pure solvent coming off, magnetic gunk left behind. Furthermore, you can't put them back together to make ferrofluid again; that would be like unscrambling (or, more precisely, uncooking) an egg.

Einstein and Szilard invented it first (1)

Demonoid-Penguin (1669014) | more than 3 years ago | (#37431946)

Presumably the 45 patents they held have expired....
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