--- Robin van Spaandonk <[EMAIL PROTECTED]> wrote: > In reply to Paul's message of Sun, 8 Oct 2006 > 21:20:20 -0700 > (PDT): > Hi Paul, > [snip] > >> I have a few questions. > >> > >> 1) At the frequencies you envisage using, > wouldn't > >> the heat have > >> difficulty entering/leaving the material? IOW > >> wouldn't you just > >> end up recycling the same heat over and over > again > >> internally? > >> (A thermal "short circuit" as it were?) > >> > >> 2) If the temperature difference is just a couple > of > >> degrees, > >> doesn't the Carnot limit severely restrict the > >> potential > >> efficiency of any conversion device? > >> > >> 3) I thought that magnetic cooling was already > >> widely used, and am > >> not aware of any OU associated with it. > >> Regards, > >> > >> Robin van Spaandonk > [snip] > >Hi Robin, > > > >This is solid-state technology and would generate > >direct electricity. > > How?
I apologize. In a nutshell the design collects MCE (Magnetocaloric effect) energy. When the intrinsic electron spins flip the entire atom precesses as it rotates. This rotation/flip gives off radiation, typically in the hundreds of MHz. Unless using specific techniques, the magnetic material absorbs nearly all of this internal radiation. The problem in most magnetic materials including ferrites is the amount of energy released is on the order of thousands to hundreds of thousands times less than amorphous & nanocrystalline material. It's the domain size at no applied field and saturation level that basically determines the amount of radiation. The MCE energy radiated by a 1 cubic inch of ferrite at 100 KHz can be a few hundred watts, but again most of this power is absorbed by the core. For a similar amount of amorphous & nanocrystalline core it can be higher than 15 megawatts. This is an energy exchange process. At 100 KHz there are 400 thousand energy exchanges. That is, 125 joules is exchanged during each phase. So the material heats up by 1 C, then cools down 1 C, etc. The goal is to prevent the magnetic material from absorbing the radiation. One idea is to use material with appreciably low electrical conductivity. In such material there are micro eddy current loops around the avalanches within the magnetic material. So part of the potential magnetic energy is being converted to eddy currents. At the appropriate time the circuit will extract as much of this eddy current as possible. In the previously provided link you may see further details regarding this MCE radiation, where is comes from, what's the cause, and the advisable methods of preventing the core from absorbing the MCE energy. For those wanting a design, here's a quote from the intro of my wiki "I began designing the MEMM over a month ago and took a look at the design and basically said, 'Hey, this is the MEG!' I began to notice the extreme similarities with other devices. They used PM's (permanent magnets) to nearly saturate magnetic material, electrical current in a coil to oppose the PM's field, high di/dt in the correct cycle. Since that time the design has evolved into another form that will hopefully be more effective than the MEG." I would be more than happy to release MEMM designs that have evolved beyond the MEG when everything is 1000% verified. My intentions are to freely publish everything in extreme detail. --- Robin van Spaandonk <[EMAIL PROTECTED]> wrote: > In reply to Paul's message of Sun, 8 Oct 2006 > I have a few questions. > > 1) At the frequencies you envisage using, wouldn't > the heat have > difficulty entering/leaving the material? IOW > wouldn't you just > end up recycling the same heat over and over again > internally? > (A thermal "short circuit" as it were?) Well, if you have heat then the device did not work. The idea is to prevent the core from absorbing the MCE energy. > 2) If the temperature difference is just a couple of > degrees, > doesn't the Carnot limit severely restrict the > potential > efficiency of any conversion device? This design has nothing to do with converting temperature differences into another form of energy. > 3) I thought that magnetic cooling was already > widely used, and am > not aware of any OU associated with it. > Regards, Yes, there are machines that use MCE for deep freezing. I am not sure what COP some of these recent machines are achieving. I received an email from a guy from France said there's a local company that achieved abnormally high efficiencies. Even so, nearly all companies are focusing on Gd alloys, which rely on achieving MCE by means of room temperature Curie point materials, such as Gd. The permeability of Gd at Curie temperature is extremely small, meaning that the most of the MCE energy would come from the battery by means of the coil and not the magnetic material. In such a case COP will always be less than 1.0. My theory predicted that domain size and saturation equate to potential MCE energy. So there are two methods of achieving small domains. 1. Simply heat up the material. At or beyond Curie the magnetic moments are randomly scattered which is essentially domains the size of a few atoms. 2. Use amorphous & nanocrystalline cores, which are extremely efficient. The reason the industry does not use method #2 is because the whole idea is to achieve very cold or hot temperatures. Amorphous & nanocrystalline cores are definitely not suited for this task. Last, but not least, trying to mechanically extract energy from temperature differences is still astronomically inefficient. Kind regards, Paul Lowrance __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
