Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
"More like a cross between an onion, a golf ball, and a roman multi-tiered arched aquaduct."

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Ferrofluid-Core Electric Power Transformers

This is a matter of efficiency
  (+3, -1)
(+3, -1)
  [vote for,

Ferrofluids have near-zero hysteresis, which is the major cause of energy-wastage in electric-power transformers. A relatively inexpensive/specialized ferrofluid is described here, just for this purpose.

Background information (1):
The electric power transformer is a remarkably simple (zero moving parts) and efficient device (often better than 95%). Its job is equally simple, to convert alternating-current electric power from one voltage/amperage ratio to a different voltage/ amperage ratio. See, total electric power is measured in watts, which generally can be thought of as being the product of volts and amperes. So, 1000watts can equal 10V x 100A, or it can equal 10000V x .1A. Transformers let us convert either to the other (or to still other combinations of volts and amperes). The reason we want to do this is because all ordinary electric wires have resistance to the flow of electric current, and this resistance causes energy to be wasted. But current is measured in amperes, so the less current, the less resistance and the less wastage. Thus we use transformers to convert power into minimal flows of current, so that it can be sent long-distance with minimal losses. However, since the associated high voltages are difficult to handle safely in such places as homes and factories, more transformers are used to lower the voltages at those locations. In this case the power losses are still minor, because relatively short distances of wire are used between transformers and electric-powered devices. "Modern civilization", which is literally DEFINED by its widespread usage of electricity, depends utterly upon transformers. Nevertheless, if you think about the Grand Total of electric power generation, and realize that just about all of it goes through at least two transformers, their combined inefficiency wasting perhaps 9% of electricity (100% - (95.4% x 95.4%)), well, you can see that even-more-efficient power transformers would be a Good Thing. (I arbitrarily chose 95.4% as being "better than 95%".)

Background information (2):
As stated in the Synopsis, most of the power losses inside a transformer are caused by hysteresis, which is a physical property of magnetic materials (such as the iron cores of transformers). It is a resistance to any change in direction of the orientation of a magnetic field in the material. Consider a simple electromagnet, which is just a nail and a coil of wire: One end of the nail will become a North magetic pole, and the other end of the nail will become a South magnetic pole. For this to happen, inside the nail, tiny regions known as "magnetic domains", which are normally oriented in random directions, must be re-oriented so that a significant percentage of them are aligned in the same direction. Keep in mind that magnetic domains are pieces of solid matter that are surrounded by other pieces of solid matter! Is it any wonder that there is resistance to such re-orientations? Now imagine forcing the North and South magnetic poles of that nail to swap places, 50 or 60 times per second! The world's electric power is mostly generated as Alternating Current, at 50 or 60 cycles per second (nationality-dependent), because transformers only work with A.C. power. (If this sounds like a Catch-22, well, just remember that Direct Current power losses over long distances through ordinary wiring will add up to lots more than only 9%.) Workers in this industry refer to a magnetic material as being "hard" or "soft", as a way of describing its hysteresis characteristics. The most efficient transformer cores are magnetically "soft", with minimal hysteresis.

Background information (3):
It should be mentioned that it is not essential to use iron to make an electromagnet. The coil of wire all by iself qualifies. However, the strength of the magnetic field is usually vastly weaker without the nail, than with the nail. (If one uses a big enough coil and plenty of Amperes, then the iron is not necessary -- but "big enough coil" means a LOT of wire, and "plenty of Amperes" means lots of electrical resistance. That's as wasteful or even more wasteful than hysteresis.) What the nail offers to an electromagnet is an "amplification" effect among the magnetic domains inside the iron. If you've ever played with a couple of bar magnets on a tabletop, you may have tried pushing one around with the other. This is a little tough to do for a significant distance, because the magnet being pushed will often spin around so that it is attracted to instead of repelled by the magnet you were holding/pushing-with. Well, the same thing happens at the level of magnetic domains: When the electromagnet coil first causes some of the domains to become aligned, they push other magnetic domains around, causing them to become aligned also. All the domains that become aligned (but many do not become aligned) will contribute to the total field of the electromagnet. Yet there is a bit of a paradox here. Permanent magnets are made from magnetically "hard" materials, and the "harder" they are, the stronger fields they have. In those materials, almost every single magnetic domain has been forced into alignment -- and they stay there because of the material's "hardness". (There may also be a difference at the atomic level, regarding the number of electrons-per-atom that contribute to the magnetic properties of the material.) "Soft" materials usually manage to leave quite a few domains unaligned, so electromagnets often have to be rather energy-consumptive to be as strong as permanent magnets. Ideally then, we'd like to have transformer cores that have maximal "hardness" per magnetic domain, but easily allows ALL its domains to flip....

Background Information (4):
A "ferrofluid" is a mixture of particles of some magnetic material (often iron oxide in the form of magnetite) with a very viscous substance like soft wax (often it is NOT wax per se, but I shall use "wax" here in the generic sense). The magnetic particles are "suspended" in the wax, much like muddy water has dirt suspended in it. In the case of muddy water, when the water is still and not swirling, then because water has low viscosity (flows easily), the dirt particles eventually fall out of suspension, leaving fairly pure water behind. Depending on the kind of dirt, this sort of thing COULD happen to dirty motor oil, but it will take quite a while for the dirt to fall out of suspension because motor oil is more viscous than water. With some really viscous stuff like wax, particles can stay in suspension for a long long time, indeed! --Well, it depends on the particle, of course. As you know, iron is fairly heavy stuff, about eight times heavier than an equal volume of water. If you could suspend particles of pure iron in the water, without it immediately rusting, then the iron would fall out of suspension quite a bit more quickly than dirt. Similarly, magnetite and not iron is used in ferrofluids, because the density of magnetite is only a little more than 5 times that of water (and again any iron would rust, while magnetite can be called "already rusted iron"). Ferrofluids are packed full as much as possible with iron oxide, which makes the wax more of a "matrix", than a "suspendor". Ferrofluids are kind of putty-like, and exhibit some rather fun behaviours in the presense of magnets. They FLOW toward magnets like some kind of life-form, exuding a psuedopod.... Ferrofluids have also been hideously expensive, partly because of the actual substance of the "wax", and partly because of the effort put into grinding the magnetite particles into incredibly fine dust (which makes suspension easier, of course). A reference I found says, "First developed for NASA in the 1960’s, ferrofluids are tiny magnetised metal particles in an oil suspension. They have now found specialised uses in a variety of specialised applications, from loudspeakers to rotary seals - but in relatively small quantities." That last is because of the hideous expense, of course -- but that first part, is mistaken about "magnetised metal particles"; NASA scientists were working with magnetite. Recently the price of ferrofluids has been dropping, possibly due to the good old supply/demand chicken/egg thing (prices go down as production goes up; but production only goes up to meet demand, which does NOT go up much when faced with high prices!). It could be the popularity of ferrofluid-based speakers, because they produce high-quality sound, thanks to the simple fact that ferrofluids exhibit practically ZERO hysteresis, and so can easily be used in conjunction with Alternating Currents of thousands of times per second...("audio frequencies").

At Last!, the Idea:
Above, the guy who got that description wrong, about what ferrofluids are, actually got it right with respect to what we need for electric-power transformer cores (and I was quite surprised to see that error, too!). Magnetite particles are FAR weaker in magnetic intensity, than filings from ground-up permanent magnets! And I did write, "Ideally then, we'd like to have transformer cores that have maximal "hardness" per magnetic domain, but easily allows ALL its domains to flip...."

Each particle of magnetic material in a ferrofluid is the same as a magnetic domain, and the suspendor- oil can simply be seen as a lubricant, allowing the domains to easily flip. All we need is a box (tough and nonmagnetic), shaped like a transformer core, filled with ferrofluid.

I especially want to repeat that this transformer-core ferrofluid should use the same magnetically hard material as is found in permanent magnets (there are many, so pick a relatively inexpensive one, that is corrosion-resistant). This material does need to be ground into powder, but I'm going to suggest that we use the same sort of "grinding" systems that are used to manufacture ball bearings -- basically huge rotating drums full of non-round bearings and grinding dust --we just run those grinders a whole lot longer. That way we get enormous quantities (inexpensive!) of tiny spherical magnetic domains (use magnets to separate them from the grinding dust, of course), which will indeed flip extremely easily when mixed with oil, and have near-zero hysteresis.

Transformer efficiency will likely jump to 99%. That wasted-power formula which I presented earlier then becomes 100% - (99% x 99%), or 2%. So, if every existing high-power transformer was replaced with a ferrofluid-core transformer, we would gain back 7% of presently-wasted electricity, for real usage, with zero new power-plant construction. I say it's worth doing!

Vernon, Nov 12 2003

Power Losses http://web.archive....vol_2/chpt_9/9.html
Transformers can lose power more than one way. Eddy currents should not be a problem here, because oil is an insulator. [Vernon, Oct 04 2004, last modified Oct 08 2008]

Ferrofluid as a coolant for transformers. http://web.archive..../complex_fluids.htm
You have to hunt through that page to find it. This is most definitely NOT what this Idea is about! Besides, if transformers are more efficient, they create less heat in the first place, and so may not need fancy cooling. [Vernon, Oct 04 2004, last modified Oct 08 2008]

Transformer basics http://www.tpub.com/neets/book2/5.htm
[half, Oct 04 2004, last modified Oct 06 2004]

Small Spheres http://web.archive.....com/technology.asp
These are made of plastic, and they aren't microscopic, but "hard" magnetic spheres of this size may be small enough for this Idea. They would also cost less than truly microscopic spheres. [Edit: The original link is dead; the images at the archived link have apparently not been preserved like the text was, sorry.] [Vernon, Oct 04 2004, last modified Oct 08 2008]

Amorphous metals http://www.metglas....c_pow_dist_appl.pdf
These are used in transformers for all the reasons [V] advocates ferrofluid. [bungston, Oct 04 2004, last modified Oct 06 2004]

Fun with Ferrofluid http://www.wondermagnet.com/ferro.html
In editing this page's bad links, one was completely lost, sorry. Hope this replacement is adequate, though. [Vernon, Oct 08 2008]

Transformers http://www.duncanam...l/transformers.html
A discussion on audio transformers, but relevant nevertheless. [neelandan, Oct 10 2008]

Transformer efficiency http://www.copper.o...ans_efficiency.html
Note core loss is 0.36% for 1500kVA transformers (= eddy current and hysteresis, or similar to no-load loss). Core loss is assumed to be constant for most calculation purposes. [Ling, Oct 10 2008]

Fortscribe.com http://www.fortscribe.com/14.html
The page where this Idea has been posted elsewhere, as mentioned in an annotation. [Vernon, Aug 31 2009]


       Another well thought out idea.   

       So you're saying the tiny spherical magnets will physically spin in the fluid at 50/60 hz? Won't that create a lot of friction?
Worldgineer, Nov 12 2003

       Well, the oil is there to deal with the friction. Sure, there will be some, but far less than the equivalent amount of hysteresis. And, by using magnetically hard material, the effectiveness of the transformer action should itself be increased, which (if true) would translate into physically somewhat-smaller transformers.
Vernon, Nov 12 2003

       Having worked in the power transformer industry, I'm going to guess that the answer has to do with the fluid.   

       While you treat the ferrofluid as a solid core for the transformer, I think you'll just turn the transformer into a giant ferrofluid mixer and end up wasting energy moving the ferrofluid around. This impression is reinforced by reference [29] and [30] in your "Ferrofluid as a coolant for transformers." link. Unfortunately, I can't find the papers referenced so I can't say for sure.   

       Another issue is that oil-filled transformers typically aren't encapsulated as the oil they sit in doesn't conduct electricty. I bet your ferrofluid does, however, so you'll need your transformers encased in epoxy. Again, these may be addressed by the references above.
phoenix, Nov 12 2003

       (+) from me. I haven't time to read it properly - and I always disliked the 'fields' sections of my EEE degree, so forgive me for not giving the idea proper comment. The vote is for the first (that I have seen) genuinely technical, referenced, lengthy idea that has structure and references.
Jinbish, Nov 12 2003

       Hmmm. But after browsing the idea (although not thinking too hard - nor reading references)... the magnetic field induced by the windings will cause the magetic particles to move in the oil. I think [pheonix]'s point about the mixer is an important issue and could scupper this idea. (the + stays though on principal)
Jinbish, Nov 12 2003

       phoenix, the answer USED to be that ferrofluid was too hideously expensive. Still, your remarks about particle movement do seem like a reasonable objection. But I do wonder. Suppose I take an iron ring and loosely wind a coil around its length, so that the overall ring can rotate inside the toroidial coil. You seem to be saying that energizing the coil will cause exactly such a rotation (and thus a flow of ferrofluid in a transformer core), and I do have doubts about that. This ring-experiment is not a solenoid, in which the starting position of the core is offset from the coil, after all.   

       Can anyone offer more info about this scenario? Thanks!   

       Oh, and about the electrical conductivity thing: Yes, I'm sure the individual particles are conductive. But the intervening oil isn't. If necessary (and as indicated at the "Ferrofluid" link), the particles could be coated with some insulator before being mixed into the oil. Hmmmm...I do think I should have mentioned that I wasn't looking for a "suspension" of particles in this Idea. I'm looking to jam-pack those particles together, with as minimal oil as needed to handle friction. --Jinbish, that will greatly reduce the freedom-of-overall-motion that you described.
Vernon, Nov 12 2003

       This is a good idea for two reasons. It may possibly save energy and it uses ferrofluids. What more could you want in an idea? +
sartep, Nov 12 2003

       If nothing else it warrants further thought or experimentation. Tell us [Vernon], did you get standard or overnight shipping on the ferrofluid?
Worldgineer, Nov 12 2003

       Worldgineer, I don't own any ferrofluid yet, because I don't want the magnetite-based kind. I want some of the magnetically-hard kind. Magnetite just doesn't have a strong enough magnetic field, for present ferrofluids to be used in power-transformer cores, or in other things....
Vernon, Nov 12 2003

       //Each particle of magnetic material in a ferrofluid is the same as a magnetic domain, and the suspendor- oil can simply be seen as a lubricant, allowing the domains to easily flip. All we need is a box (tough and nonmagnetic), shaped like a transformer core, filled with ferrofluid.//   

       I think a problem might arise here. It is my understanding that the "magnetic domains" in a nail do not physically flip - that is to say, bits of nail do not move. If this were the case, the resistance would be very high - and nails would get deformed or at least heat up noticeably in magnetic fields. In a ferrofluid, the suspended particles are not themselves magnetic domains", but are more like tiny nails. The paragraph above paints a picture of tiny particles realigning themselves, lubed in oil. I do not think you can lube up a magnetic domain.   

       Where is the energy loss? I suspect that some, at least, is electrical - my recollection is that every change in a magnetic field generates an electrical force which in turn generates a magnetic field opposed to the change. It is hard to see how extra KY jelly would stop that.   

       Finally - even very finely ground iron will be pulled to one side of even a very thick gel if a magnet is applied. I have a vial of ferrofluid and was surprised to see that even after a year of sitting on a shelf, it did not noticeably settle. I admit I am not sure why.
bungston, Nov 12 2003

       What about taking something that is mostly a solid, but has some of the properties of a gel (I'm actually thinking of a particular styrenic/olefinic alloy here) and filling it with a very high loading (90 - 95%) of a fine, pure iron powder in the 1-2 micron range? (yes I know that pure iron is a fire hazard by itself and can combust incredibly easily. However once encapsulated this is no longer an issue)
The specific material I'm thinking of has a TG (glass transition temperature) of something like 40 degrees F. Wouldn't this bypass the loss to movement issue? Also I'm reasonably sure that this woud have a much lower cost than ferro fluids, and it gives you the "hard" material your looking for. Another benefit is that this material would be injection moldable.
soundman, Nov 12 2003

       bungston, certainly the polarity of a magnetic domain gets flipped, and perhaps the domain itself can be defined as just a region in which all the atoms are willing to flip together. I think there is physical flipping at the atomic level -- perhaps only an electron or two within each atom -- and I agree that it doesn't make sense at the domain level. Anyway, in this Idea, the goal is to make it easy for magnetic domains to actually physically flip. Just think! When influenced by a steady alternating current, say 60hz, each spherical domain simply starts rotating at that rate, with Conservation of Angular Momentum HELPING. And while friction in some places will be energy-wasting, making oil necessary, in other places neighboring spheres will simply rotate together like meshed gears, and practically zero "rolling friction". Also note that at this small scale, a mere 60-things-per-second is trivial, compared to many other events that can happen (collisions during thermal agitation, for example). So, I still think this Idea needs to be tried out.   

       Soundman, it looks to me like you are describing an alternate matrix in which the domains CAN'T rotate easily. Also, please keep in mind that the overall effectiveness of a magnet depends on the "density" of particles in a cross-section of the magnet. You weaken it if you add too much filler. And this is why I want to "jam-pack" (well, not so tightly they can't rotate!) spherical domains into a transformer-core-box, with minimal oil.
Vernon, Nov 13 2003

       The question remains: is the energy loss related to physical motion and friction, or is it lost to generation of an opposing electromagnetic field? If the former, this idea is good. If the latter, this idea is bad. [Vern], you mentioned the larger power losses in DC transmission. Where does it go? Is this not also because of the generation of an opposing field?
bungston, Nov 13 2003

       bungston, the hysteresis power loss in a transformer really is related to an actual shifting of matter, to some degree. For proof, consider the experiment in which you take two hard steel bolts, some paper clips, and a magnet. Test one of the bolts with the magnet to make sure it is a magnetic material (some hard steel bolts are nonmagnetic); then set that bolt and the magnet aside. Take the other bolt and make sure it has not previously been magnetized, by seeing if it can affect the paper clips. Then lift the bolt more than a meter off the ground, and drop it head-first toward a block of concrete. Repeat that several times, and now hold that bolt near the paper clips. It will now be somewhat magnetized! Thus we know that some sort of physical shift takes place inside steel, which can be associated with an overall nonrandom alignment of magnetic domains.   

       Direct Current losses are entirely due to electrical resistance of wires. Since there is no good way to change the voltage/amperage ratio of high-power DC, it has to be generated and transmitted at the intended destination/usage voltage. High power at such lowish voltage means high amperage flowing through wires, and high resistance losses.   

       Did you know that in the early days of the electric power industry, there was a kind of battle between Thomas Edison, who favored DC, and George Westinghouse, who favored AC (specifically the "three-phase" system invented by Nikola Tesla). If Edison had won, there would be power plants every 3 kilometers or so, to reduce power transmission losses by reducing distance between generators and users. The "Not In My Back Yard" syndrome probably contributed to the defeat of Edison's plan.   

       q2cannonfodder, that is a good question. Depending on the size of the particles, it seems to me that such clumping as you describe can reasonably be expected, if the particles are large enough (while extremely small particles will be thermally jostled into random orientations), simply because we WANT the particles to be able to rotate freely. But this is not a bad thing, since the magnetism between any two particles will be relatively feeble, simply because they ARE particles. The overall transformer field will be able to make them rotate. Still, I do see one not-so-pleasant consequence, which obviously deserves study, before this Idea is implemented on a wide scale.   

       Consider two bar magnets on a Teflon tabletop, and a couple of round "coasters" to which Teflon has been applied on one side. With Teflon on Teflon, the coasters will freely move around on the tabletop. Now glue the magnets onto the non-Teflon-coated sides of the coasters; we have now created the 2-dimensional equivalent of a couple of spherical magnets. Placed near each other, they will attract end-to-end with noticeable force. If you grab one of the magnets and rotate it, you may have to prevent the other from swinging along in a kind of orbit, with the two magnet-ends still pointed at each other. So apply such prevention, which is equivalent to the spheres being surrounded by other spheres, and again rotate the first magnet. The second will now also rotate in place, but you will notice that it will take a certain effort to BEGIN that rotation, to cause the two magnetic poles to increase their distance via rotation. We can immediately see that inside a transformer, some energy is going to have to go into making that effort to begin rotations -- but wait! As you near 180 degrees of rotation, the OTHER two poles of the two magnets are now starting to attract each other! The prior effort put into distance-increase can now be gained back! YOU can't gain it back in this table-top experiment, but be assured that electromagnetic systems WILL gain it back.   

       So, what is the not-so-pleasant consequence? This: The effort expended, plus the later gain-back, will likely have some sort of affect on the Frequency Of Operation of the transformer. A somewhat distorted Alternating Current sine-wave can be expected. Whether or not this will turn out to be a problem remains to be seen. Ordinary electromagnetic machinery will not be affected at all, and "synchronous" motors, the speed of which are controlled by A.C. frequency, will only be off by a fraction of a second at any given moment. But what of electronic systems? Many will not be affected because they rely only on AC which has been converted to Direct Current. As to others, I don't know enough to say. Thus the necessary experimentation.
Vernon, Nov 13 2003

       So I finally got irritated at this and decided to learn some more about it. And it looks like [Vernon] is right, and this idea is good. Linked is an article about "amorphous metals" which more freely permit domain reorientation - which it seems is a major cause of energy losses, as heat. The reasons making the amorphous metals more efficient are in essence those listed above by [V]. So: a bun from me after all. And more educational than fart bags.
bungston, Nov 18 2003

       Thank you, bungston.
Vernon, Nov 18 2003

       Get cracking. I expect to see this one in a science journal write-up by 2005. +
RayfordSteele, Nov 18 2003

       i think price may be a major factor. So many less expensive ways to save, higher voltage, 3p etc. Notice how little cooling is used in the current setup? Not much waste considering everything. Pretty sure this is pretty well baked and we only await the arrival of new hot semiconductors to start harvesting the benefits of higher efficiency transformers. Conventional magnetics will have to do till then.
WcW, Oct 10 2008

       if you look at the history of ferro fluid usage and problems of chemical and physical stability have been the bane of practical applications. Unless you can solve this problem use in transformers is unlikely. Furthermore I think your idea would be a lot stronger if you could give some numbers on current energy leakage in the form of heat and what degree you expect your idea to reduce it. Last i read heat was still a problem in ferro fluid devices and this "magnetic friction" increased as the fluid degraded until it destroyed the device. (A "fluid" of tiny spheres, short of the scale of Buckyballs is not going to serve IMHO.)
WcW, Oct 10 2008

       "It is possible to make a substance with reduced hysteresis losses"   

       That is what the idea is about, the premise which can be tested, and without which the whole idea falls apart.   

       "If we wound three identical coils (within real world "identicalness") and stacked them with M4, M6, and M19 core materials what might we expect to be the differences?   

       One of the differences would be the amount of inductance produced. Again, to simplify our model, let us assume a PP trans and no DC imbalance. Then the material with the highest perm will produce the most inductance. Here the pecking order would be M4, M6, M19 in descending order.   

       Another difference btwn the materials would be the amount of losses. This is generally stated by manufacturers of the electrical grades of steels as a watts per pound at a specific flux level. Usually they will provide a graph that shows the relationship btwn flux level and losses. the higher the flux level the higher the losses. Again, M4 will exhibit the least amount of losses and M19 the most losses."   

       from the net, link provided.   

       [Vernon] is ascribing magical properties to ferrofluid, in another idea too, a motor. This ferrofluid with zero hysteresis is the phoenix tail feather inside the birch rod, which V waves in our face while mumbling a ton of magic nonsense.   

       It is nonsense, after all.   

       Now I cannot disprove this idea by grinding magnets into dust and dispersing in oil and measuring its hysteresis and finding a finite value. [Vernon} is sure to accuse me of doing something wrong. It is the "proof that the invisible pink unicorn exists" thing all over again.   

       But [Vernon] can prove me wrong.   

       He can make a small quantity of this ferrofluid, seal it up in a glass vial, and send it somewhere for testing (or test it himself) and show that it has - (1) permeability greater than that of air (2) saturation flux comparable to silicon steel (3) zero (or greatly reduced) hysteresis loss.   

       Until then, look upon this idea as the deluded ravings of a man on the moon. Shake your heads, smile kindly, and walk on.
neelandan, Oct 10 2008

       [neelandan], are you having fun yet? I specifically stated that ferrofluids have near-zero hysteresis, which is a measurable fact, compared to other magnetic materials. I did not claim they have zero hysteresis, which might qualify as a magical thing. Why did you lie about what I wrote?
Vernon, Oct 10 2008

       the conception is sound enough but no such material currently exists and declaring by fiat the properties of a theoretical material is pointless. Fact is that people have been working for decades to produce stable ferrofluids and have met with huge frustration. I think lukewarm superconductors are a going to be great too, but i'm not putting them into my designs just yet.
WcW, Oct 10 2008

       "no such material currently exists" [WcW], what are you talking about? Ferrofluids do exist in quite a variety of formulations. And oils that can withstand transformer heat are in wide use (originally, poly-chlorinated biphenyls or "PCB"s that are now being phased out).   

       In this Idea I'm not striving for a suspension of particles; I'm only striving for a lubrication of sphere-shaped "hard" magnetic domains. And I'm only claiming that lubricating the domains so they can flip easy is more energy-efficient than letting them flip inside a solid substance.   

       Finally, it is known that the maximum intensity of magnetic field that an ordinary (iron oxide based)ferrofluid can handle is lots less than the maximum intensity that solid iron (or other metal/alloy) can handle. This Idea should allow fields that APPROACH the intensity that solid metal can handle, simply because the spheres are specified as being mostly made of solid metal, instead of some compound where half the atoms don't have any significant magnetic propereties**. It is the gaps between the spheres that lessen the maximum total field intensity here (and the smaller the spheres, the more closely they can be packed and the more closely we can approach the effectiveness of solid metal).   

       **Ferrofluids incorporate compounds simply because they are less dense than metal, which makes suspension of the particles much more possible than otherwise. Since I don't care about suspension here, I can specify metal particles/spheres.   

       Now, would you care to be more specific in your too-generic claims about where this Idea fails to be workable? (You, too, neelandan!)
Vernon, Oct 11 2008

       well why not start there? How large are these spheres? What material are they made of? Is the reduced inductance/loading going to offset the friction of balls spinning at 60htz in lubricating fluid? Small enough to spin without burning up is going to be very small. I guess even after reading the idea several times I still don't understand exactly what you are proposing. Is this a transformer with a liquid magnet core, a transformer with liquid and magnets in the core, or something else entirely? I think that if you could just sum up the ACTUAL INVENTION rather than the science you think would be foundational to it (about which there seems to be little argument) we could understand it. I for one doubt that magnetic buckshot in oil is about to replace solid core transformers. Furthermore the assertion that 7% of electric generation is wasted in transformers is false.
WcW, Oct 11 2008

       [WcW], the main text specifies a magnetically hard material. It could be the same material that they make modern high-power permanent magnets out of. One advantage of such a material is that it can handle higher magnetic flux than ordinary transformer-core material, so that balances against the fact that so many voids will be present between the spheres.   

       And yes, the spheres need to be quite tiny; I said so, because I do know that frictional heating will be reduced in that case. And, just because we might not be able to make them now, or easily make them now, is irrelevant; this IS the HalfBakery, remember. What matters most is that they be smoothly spherical so they can rotate easily at 60Hz.   

       Finally, I suggest you look again at the way I computed my energy wastage figure. I ONLY talked about power going through just 2 transformers. Why don't you get some more up-to-date figures for modern power-transmission transformers, and take into account the actual number of transformers involved, in getting power from the power plant to a residence. The energy-wastage percentage I arrived at may be smaller than the truth!
Vernon, Oct 11 2008

       Points well taken.
WcW, Oct 11 2008

       Hello Vernon - I also had an idea like this after reading part of the ARRL handbook. What we need to do is actually test this design. I noticed some legitimate considerations above, namely the "mixing" hypothesis. Anybody who has played with a split ferrite core which has not been properly tightened knows just how significant these losses can be. For this to work, some kind of mechanical constraint would need to oppose this kind of motion. I don't think this would be especially difficult if one contained the fluid. There may still be some loss related to movement, but those particles would still transmit magnetic flux if they are forced to flow through a ringed container. The coefficient of friction for ferrofluid is so low, that I doubt the degree to which mechanical loss will play a role. Only experimentation can tell!   

       Another point mentioned above was resulting wave form irregularity secondary to mechanical motion. While hopefully ferrofluid motion will resonate at the driven frequency, its likely that this will be a factor that affects the application of this transformer. For general power distribution I suspect that one would just notice little oscillations imposed over the standing AC sign wave. If the idea develops, I am sure people could make designs that dampen, negate or resonate these waves.   

       The hypothesis presented here deserves experimentation. Somebody should actually build this. If you are willing to collaborate, Fortscribe.com would like to work with you. I borrowed your piece and posted it up on Fortscribe with some of my own revisions/commentary.   

       I don't care about credit, I just think we should explore ideas like this.
Fortscribe, Aug 27 2009

       [Fortscribe], I have no objection to the idea being spread. I think I shall object a bit, though, to certain aspects of how you went about copying it. I quote from Fortscribe.com: "Unfortunately the author is unknown." WHAT A STUPID LIE.   

       Here at the HalfBakery you can click on the user who posts something, to reach a specific page for that user. My page here does provide some information (at least one link) that can be used to find out some other information about me. Did you even try? Apparently not, if you wrote: "I don't care about credit" in your Aug 27, 2009 post.   

       I see that Fortscribe.com takes a politically "conservative" stance. From what I've seen in life, it is typical of people of that political persuasion to try to steal stuff from other people, without giving them credit or even trying to give them credit, because they greedily want the credit and potential value of that stuff all for themselves. A particular point regarding that is at the end of this quote from Fortscribe.com:   

       "Very recently, there have been others who have taken to examining this idea more closely. Our sources report that some practical and more efficient transformer designs have been developed! Unfortunately, there are some details to these projects that I cannot share with you at this time. Some engineered solutions will probably become intellectual property ..."   

       Sorry, not likely, exept in the excessively-greedy dreams of political conservatives, since this Idea has been in the Public Domain for lots longer than the 1-year period the Patent Office allows, for patenting something, and all of those engineered solutions, if they are following this Idea at all, will include a container for ferrofluid, shaped for the purpose of acting as a transformer core. This Prior Art, a plain-language description of a worthwhile Idea, will preclude anyone, even me, from obtaining a basic patent about it, anywhere. And that's the way I wanted it; all of civilization needs to benefit from this Idea, not just the greedy political conservative folks who constantly try to constrict resources for their own benefit.
Vernon, Aug 31 2009


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle