The Ferrofluid Transformer:
"Alternative approaches to developing our energy infrastructure" - Perankhscribe
One day in a winter past, I found myself reading the ARRL handbook for fun. As I came upon a section regarding the construction of oscillation devices for radios, I reviewed an interesting commentary discussing the limitations of the standard ferrite core in transmitting higher frequency ac-waves. The book went on to explain that one possible solution to this issue was the incorporation of powdered iron transformers. The rationale for this approach, in a nutshell, was to optimize some of the transformers properties. Particularly, this dealt with a form of inefficiency known as hysteresis.
While powdered iron is suitable for some radio applications, it still is plagued by several issues that make it undesirable for usages in everyday application. This interested me and I reflected over what I understood regarding the issues of "magnetic hardness" and hysteresis. As I did this, I thought back to the fun I used to have with Neodymium magnets and ferrofluid. For those of you unfamiliar with this fun substance, Ferrofluid is a mixture of iron particles and organic detergents and has found its way in many applications from speakers to stealth planes. The price of this substance has been coming down in recent years and you can buy it fairly cheap on e-bay.
For reasons as capricious as they were practical, I wondered about how this substance might behave as an element of a ferrite core. I figured somebody out there might have considered it already so I did a quick search. Sure enough, there were some people who had thought some about this in the blogsphere. Provided here is some background which I have borrowed from a 2003 forum post taken from Halfbakery.com. The original author of this work is named Vernon Nemitz. He has graciously allowed us to re-post his work as he wants ideas like this to benefit mankind. We would like you to know however, that he is not politically affiliated with Fortscribe. Please do not attempt to harass him for political viewpoints expressed throughout our website.
BACKGROUND:
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. (
1): The electric power transformer is a remarkably simple (zero moving parts) and efficient device (often better than 95%). It functions to convert alternating-current electric power from one voltage/amperage ratio to a different voltage/ amperage ratio. Total electric power is measured in watts, which generally can be thought of as being the product of volts and amperes. 1000 watts can be achieved by multiple combinations. For example, 10V x 100A or 10000V x .1A.
Transformers let us convert between these combinations. 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. The energy wasted by resistance is proportional to current squared times the resistance of the path the electricity follows (Resistance being a complicated product, which for our purposes mostly depends on the length of the wire.) Thus, higher currents result in a significant amount of wasted energy. To deliver power over long distances it is wise to convert to higher voltage/current ratios.
Thus we use step-up transformers to convert power to a high voltage/ low current form, so that it can be sent long-distance with minimal losses. However, since the associated high voltages are difficult to handle safely, step-down transformers are used to lower the voltage before it enters your home. Thus safety is maintained and power losses are still minor.
Modern civilization is literally DEFINED by its widespread usage of electricity and this depends utterly upon transformers. Imagine the great sum of all the electrical power generated. Note that just about all of it goes through at least two transformers. While transformers are generally efficient, their combined inefficiency does waste a substantial portion of energy. Consider a 95.4% efficient transformer. Since we use two transformers in sequence, we can estimate that this setup results in the loss of 9% of our electrical power (100% - (95.4% x 95.4%)). Since we probably won't be able to replace the utility of the transformer anytime soon, it seems logical that more-efficient power transformers would be desirable. Notice that small improvements in transformer efficiency can result in substantial power savings. Between 95.0 and 95.4 we save almost 1% of our total generated energy!
(2): As stated earlier, 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%.)
(3): Workers in the energy 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. 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 coil with many turns of wire and a large current, then the iron is not necessary -- this translates to "ALOT of wire, and the substantial loss of energy from a large current/resistance combination. 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.
(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").
FUTURE WORK:
While the idea to use Ferrofluid as a transformer core is not unheard of, it has not received enough public examination. Ideas like this seem to be completely ignored by "eco-friendly" politicians like Obama.
Worry not folks, the idea is not dead. 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 and while we here at Fortscribe value free exchange of ideas, we do not wish to betray the confidence of those who work diligently to invent. How would you feel if you worked your butt off only to let some foreign company steal your work?
We want you to appreciate that projects like this offer us alternatives to poorly conceived giant wind farms or solar panels. Sure, this idea does not provide us an ultimate solution by itself. However, a few percent increase in power availability from all power sources is worth more than the fraction of a percent increase in power we gain from converting Montana into a wind farm. (But I digress, read my upcoming article on Homemade power generation if you want to know more about that.)
Coupled with the safety advances in Nuclear energy, solutions like this offer far more promise than anything the eco-left is bent on dictating. Big surprise, eco-marxists would rather keep electrical power as a valuable commodity that they can levy to keep you in line.