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Author Topic: Do permanent magnets " DO " work?  (Read 46831 times)

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Well that's a great start.... It seems you can't use bold type in the subject heading!

I have my own perspective on this subject. I have many different permanent magnet based engineering aids in my workshop, from DTI stands to magnetic chucks. They do work, they hold material down to be sculpted.

I was also going to say virtually the same thing as Brad, without a PM for a motor the armature has little to act against. Doesn't that constitute work?

For myself it's just another way of looking at a subject. Let's get started. Please keep it clean!   ;) O0

Cheers Grum.

As a post script, the oldest Lister engine in my collection was built in 1911 it has a Hill's double horshoe magnet magneto. I have never touched it in any way, still produces a fat 1/2" spark on every flick. Built to last, including the magnetic field....... ;)


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Believing in something false doesn't make it true.
Does making something more efficient constitute doing work?  Like you and Brad I have seen how much more efficient a DC permanent magnet motor is compared to a conventional DC motor with wound field coils.  We had to apply power to the field coils in order for the motor to produce any torque.  In a DC permanent magnet motor the coils are replaced with magnet and magically we now don't have to supply power for the magnetic field for the rotor to work against.  So if the magnet replaces something that uses power doesn't that mean the magnet is doing work?

I am going to make a prediction about this thread.  I think there will be some looking at this thread that will see enough evidence to change their minds about magnets doing work.  Maybe for and maybe against.  However I think most of the people that will read this thread have already made up their minds and will not be persuaded either way no matter how much evidence is presented either for or against the idea of magnets doing work.

I personally think those that don't believe magnets can do work are being overly nit-picking.  I can say a gasoline (petrol for our friends across the water) powered engine doesn't do any work.  It is the gasoline that is doing the work.  But is it really the gasoline?  It could be argued the gasoline is only reacting to being compressed and ignited to combine with the oxygen in the cylinder.  Where do we draw the line and say this is where the work is being done.

What part of an electric motor can we say is where the work is being done?  Is it the coils of wire on the rotor that are doing the work?  After all with no current flowing through those coils of wire then there would be no mechanical torque.  Is it the rotor?  Without the rotor the coils couldn't transfer the torque to the shaft so the torque can be used.  My own personal opinion is ALL parts of the motor are contributing to doing work.  If you take away any part of the motor then the rest is useless and can't do any work.

Just my 2 cents (pence) or whatever.

Respectfully,
Carroll


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Good to see this thread started Grum.

First up,i hope ION joins us here,as we once and for all answer this question correctly,by way of accurate testing.

My thought toward this experiment is a simple setup,where we measure temperature differences between different setups of the DUT.

I believe that if i were to make a sealed box for the DUT to be placed in,and then measure maximum achieved temperature within that box of the various setups of the DUT,then we could get a clear indication as to whether or not the PMs were responsible for any temperature increase.

I would need to build a base to carry a wound rotor and brush assembly--timber would probably be best.
We would also need to be able to change out steel laminated stator blocks for PMs easily.
P/in would have to be limited,by both way of the power supply,and a breaking system on the rotor to keep the RPM at a set range. This is where i can kill two birds with one stone,in that i can use my eddy current heat generator as a eddy current break to maintain the same RPM throughout the testing.-->one would think that if the RPM is the same,then the current draw would also be the same,but that is not the case,as i found out with previous testing in another experiment,as there will be very little BackEMF produced by steel laminated blocks as stator blocks. So instead of using steel laminated blocks for the stator,i will use weak ceramic magnets to start with. Once we have gained our maximum heat within the sealed box,i will then change out the ceramic magnets for strong neo's,and carry out the test once again. After all the numbers are in,we then have to place a good size resistor in the box,and deliver the same amount of power to that resistor as we delivered to the motor. If the resistor cannot produce the same amount of heat within the box,we then must go to plan B (which i dont have yet),and carry out a varifying test.

To me,the PMs do work in a DC motor,as every action has an equal and opposite reaction,and so if the action is doing work,then it must be true that the reaction is also doing work.

Some may say-but the PMs are stationary,and so no work is done. But what then with an outrunner motor,where the rotor is the PM,and the stator that is stationary are your windings--the PM now has motion,and so must be doing work.

It is my thought that when i replace the weak ceramic magnets with stronger neo's,even at the same RPM,the current draw will drop on the DUT,due to the stronger magnets creating a larger BackEMF--would this not be work being done ?,decreasing power to the motor,but increasing mechanical output power-->what did that,if nothing else changed?-->but this is just a guess ATM,and actual outcomes can only be had by way of experimentation.


Brad


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Here's an experiment for you Brad. It should be easy for you to set up and measure.

Make a flywheel on good bearings. Mount a PM to the edge of the flywheel, or two opposite each other for balance, or four or however many you like, the more the merrier. Make the magnet mounts so that you can easily replace the magnets with an equal-weight lump of steel or lead. Place a coil on a frame near the edge, so that the magnets swing past the coil as the flywheel rotates. Arrange a load like an LED or small incandescent bulb or a simple resistor for the coil, the heavier the load the better.

Now spin the flywheel up to a known RPM, and time how long it takes to come to a stop. Run the test 10 or 20 times with magnets in place,  the more the merrier, take the average time to stop. The bulbs or LEDs will flash or the load resistors will heat up a little.  To make it easier you can spin the flywheel up past your desired test RPM with compressed air blast, then remove the compressed air blast,  and then start your timer when the flywheel slows through your test RPM. 

Run many trials in each condition so that random errors will average out. Make your measurements carefully, even automate the measurements if you can.

Now replace all the magnets with the lead weights and repeat the tests.

You will find, if you are careful, that the flywheel _WITH_ magnets will take less time to come to a stop. The magnets are transferring energy from the flywheel to the coil. The flywheel with just the lead weights will take longer to come to a stop. In both cases you are starting with the same initial stored energy, since you have a flywheel with equal weight-and-balance spinning at the same starting RPM.

The magnets do not create energy, nor do you extract energy from the magnets, in order to light the bulbs or heat the resistors. The energy comes from the energy you put into the flywheel when you spun it up. When the magnets are present, some of this stored flywheel energy is transferred to the bulbs or resistors. When there are no magnets, the energy stays in the flywheel and only its bearing and windage losses cause it to slow down, so it continues to turn for a longer time.

You can even make this system precise enough to calculate the energy changes, and you will see that the energy dissipated in the coil-load arrangement is equal to the energy difference represented by the difference in rundown times between the flywheel with magnets, and the one with just weights.

Or you can even "invert" the system, using fixed stator magnets, and putting the coil(s) and loads on the flywheel. You will find the same result: the rotor will turn longer when the stator magnets are replaced by chunks of lead, or just omitted entirely since there are no balance issues.  The first system above is the "outrunner" where magnets are moving past coils, and the second system is the "inrunner" where coils are moving past magnets. You will find in each case that the system _with_ magnets, generating power in the coil, will stop faster than the system _without_ magnets. The magnets just transfer energy from the moving flywheel to the coil+load, they do not add energy to the system.




   

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Interesting topic this gentlemen!  O0

What is 'work' ?

Wiki has three options on its 'work' disambiguation page that can help us answer this question:

Work (physics), the work done by, or energy transferred by, a force acting through a distance

https://en.wikipedia.org/wiki/Work_(physics)

Work (electrical)
, the work done by, or energy transferred by, a force from an electric field acting on a charge through a distance

https://en.wikipedia.org/wiki/Work_(electrical)

Work (thermodynamics)
, the energy transferred from one system to another by macroscopic forces measurable in the surroundings

We can decide if these definitions are correct between us, and which if any apply to the DUT project here.

Are the three options inclusive ?


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Of course magnets can do work, or put another way you can extract energy from a magnet.  One model for a magnet is given by its surface current equivalent.  You can model a magnet by replacing it with an air space of the same shape and volume then have a surface current flowing around it.  The nearest thing practically is a single layer coil of closely spaced fine wire carrying the current.  In other words it is an air-cored electromagnet.  The current needed is huge so you can't actually make such an equivalent device, but it is useful for doing magnetic domain analysis of systems with PM's.  The theoretical device does not suffer from resistive losses, so when energized the power input sees a short circuit and has to be driven from a DC current source.  Of course in the real PM that current is the aggregate effect of all the atomic current circulations (electron spins and orbits) responsible for its magnetism.  Now if you have a DC electromagnet, can you extract energy from that DC source simply by using it in some magnetic assembly? Of course you can, you only have to induce a DC voltage onto that current generator.  Normally this is done by having a changing magnetic field, so you can't get that DC voltage indefinitely.  And to get that field back to the starting conditions you induce the opposite polarity voltage that feeds all the energy you gained back.  So normally you can't continually extract energy.

IMO the secret to getting power from a magnet is to have some DC induction into a coil that does not rely on a changing magnetic field.  And that is heresy to conventional physicists.  Induction involves electric field eddies or circular electric fields.  The only recognized way this is achieved is with a time-changing magnetic field where the basic formula tells us that the closed-line integral of the electric field is equal to the differential with respect to time of the surface integral of the B field, which in transformer parlance says the volts per turn is equal to the rate of change of flux.  But I believe there are other ways to get an electric eddy field.

One possibility comes from the Marinov generator where current (electrons) flow from a brush onto a rotating slip-ring.  The electrons get a sudden acceleration as they flow onto the ring, and at the other brush get a sudden deceleration.  We are taught that accelerating electrons radiate, and here we have a DC current stream that is radiating from a very small region.  What does that radiation look like?  Clearly it is DC, we don't have electrons flowing back and forth to create AC.  If you do the math you find that very close to that point you do get a closed loop DC voltage from the electric field.  It should be possible to measure that to prove whether this is correct.  So if our non-solid state specialists like Grum and Tinman want to make something here is a worthwhile project.

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Of course magnets can do work, or put another way you can extract energy from a magnet. 
Or more correctly, you _believe_ you can extract energy from a magnet, but you can't actually _do_ it.
Quote
One model for a magnet is given by its surface current equivalent.  You can model a magnet by replacing it with an air space of the same shape and volume then have a surface current flowing around it.  The nearest thing practically is a single layer coil of closely spaced fine wire carrying the current.  In other words it is an air-cored electromagnet.  The current needed is huge so you can't actually make such an equivalent device, but it is useful for doing magnetic domain analysis of systems with PM's.  The theoretical device does not suffer from resistive losses, so when energized the power input sees a short circuit and has to be driven from a DC current source.  Of course in the real PM that current is the aggregate effect of all the atomic current circulations (electron spins and orbits) responsible for its magnetism.  Now if you have a DC electromagnet, can you extract energy from that DC source simply by using it in some magnetic assembly? Of course you can, you only have to induce a DC voltage onto that current generator.  Normally this is done by having a changing magnetic field, so you can't get that DC voltage indefinitely.  And to get that field back to the starting conditions you induce the opposite polarity voltage that feeds all the energy you gained back.  So normally you can't continually extract energy.

IMO the secret to getting power from a magnet is to have some DC induction into a coil that does not rely on a changing magnetic field.  And that is heresy to conventional physicists.  Induction involves electric field eddies or circular electric fields.  The only recognized way this is achieved is with a time-changing magnetic field where the basic formula tells us that the closed-line integral of the electric field is equal to the differential with respect to time of the surface integral of the B field, which in transformer parlance says the volts per turn is equal to the rate of change of flux.  But I believe there are other ways to get an electric eddy field.

Now you have it right: you _believe_ it can be done.  But you cannot cite any instances where it actually _has_ been done, nor can you do it yourself.

Quote

One possibility comes from the Marinov generator where current (electrons) flow from a brush onto a rotating slip-ring.  The electrons get a sudden acceleration as they flow onto the ring, and at the other brush get a sudden deceleration.  We are taught that accelerating electrons radiate, and here we have a DC current stream that is radiating from a very small region.  What does that radiation look like?  Clearly it is DC, we don't have electrons flowing back and forth to create AC.  If you do the math you find that very close to that point you do get a closed loop DC voltage from the electric field.  It should be possible to measure that to prove whether this is correct.  So if our non-solid state specialists like Grum and Tinman want to make something here is a worthwhile project.

Smudge

And just how does the experiment you describe prove that permanent magnets can do work? You will find the same results as before: it takes more power to spin a system containing magnets to a given RPM than it does to spin the identically weighted and balanced system without magnets.
   

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Dear Smudge.

May I humbly remind you that you were going to provide us with a plan, this was some months back, another thread.

I would love to give your experiment a try as soon as I'm able.

Kind regards, Grum.


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I will join the discussion, but I might add that thermal methods are to be used when other methods become ambiguous or fuzzy.

Regarding whether PM's can do useful work, I believe it may be possible, but not the way most folks are doing it i.e using the springy push pull of magnets in attraction or repulsion or their force coupling or electrical induction methods.

If it is possible, I believe methods other than what I mentioned need to be created and evaluated, as these  have been fairly well attempted by many tens of thousands of experimenters and proven to not work, or barely work such that they are  difficult to measure or demonstrate, AFAIK.

We use the term "useful" work and although magnets can exert a powerful force, you would expect that such magnets alone in an device, (without electrical input if possible), would also produce usable power in the range of hundreds of watts or more. We do not find this to be the case.

Methods I would investigate if I had the time, would be a way to somehow releasing the energy used to create the alignments in the first place, and thus having a sort of solid state battery.

Other method s I have contemplated would be along the lines of Smudge's work i.e somehow directly coupling to the aligned electron spins.

Another method would be to tap into an avalanche effect that may occur in soft iron through an applied flux.

There are more, but all for now gotta run.
« Last Edit: 2016-08-11, 00:21:58 by ION »


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And from the other thread:

With a magnet on the flywheel passing a coil to generate current, the magnetic field of the magnet is always there, it is not the movement of the flywheel, the flywheel just brings that field into proximity of the coil for a time thus generating current in the coil. That is the flywheel did not create the energy, the magnetic field yes, the flywheel was expended energy only to move that field too and from the coil.
You can do the measurement yourself if you are careful enough: The flywheel did not "create the energy", you stored the energy in the flywheel when you used some method to spin it up. The flywheel expends energy to move the PM's field to and from the coil, yes, and this results in the flywheel slowing down (or requiring more power to maintain speed). The energy put into the coil exactly equals the energy subtracted from the flywheel's motion (or the extra power put in to maintain speed) minus losses. The magnets participate only in the same way the hammer participates when you break rocks with it. The hammer doesn't "lose energy" when you break rocks, it only transfers energy from your arms to the rocks. Remove the hammer and nothing happens, you don't break rocks and _you don't get as tired_ from swinging your arms in the same way. Remove the magnets and you don't transfer energy to the coil and the flywheel takes longer to come to a stop, or requires less power to keep moving at the same speed.

Quote

Another way, a magnet held above a piece of steel and the steel rises up to the magnet when close enough, what created the energy to rise the steel? the movement of the magnet closer to the steel or the movement itself? ;) Or is it the magnetic field?


You need to consider a complete cycle. There is "stored Magnetic Potential Energy" when you have the magnet separated from the steel, and this stored energy is returned when you approach closely enough. The complete cycle starts and ends in the same arrangement though. Start with the steel attached to the magnet, apply work to separate the two --- now you can see that you have stored energy in the arrangement "Magnet distant from steel". It is this work that is returned when you now allow the magnet to approach the steel and wind up with them stuck together again: a complete cycle, and the only work came from whatever means you used to separate them in the first place. Or start separated and finish separated again-- same thing. If you only look at half the cycle, you are ignoring the energy that is stored in the system in the first place. The same mistake is made wrt gravity by people who only consider half the cycle and ignore the storage of energy in the potential energy of height in the gravity field.

Quote
A perminent magnet does create energy, the problem is to extract that energy you may have to expend more than you get back.

Regards

Mike 8)

Er....  Do you think you can get more energy out of the magnet than was used to magnetize the bulk material in the first place, regardless of how much you have to spend to do it?
Where do you think that energy comes from? What changes when you extract it from the magnet? Does the material change in any way?
   

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Or more correctly, you _believe_ you can extract energy from a magnet, but you can't actually _do_ it.
Now you have it right: you _believe_ it can be done.  But you cannot cite any instances where it actually _has_ been done, nor can you do it yourself.

And just how does the experiment you describe prove that permanent magnets can do work? You will find the same results as before: it takes more power to spin a system containing magnets to a given RPM than it does to spin the identically weighted and balanced system without magnets.
I am not talking about spinning magnets.  In the Marinov generator the magnets do not move.

Aspden pointed out that if you add the field from a magnet to the field from a coil you get a field energy related to the square of the sum field, and if you look carefully at the different components of (Bm + Bc)^2 you find the 2*Bm*Bc term that represents energy drawn from the magnet.  The energy is easily accounted for by considering the change in field from the initial magnet field Bm to the final field Bm+Bc.  That change creates the E field eddy that "loads" the atomic dipoles.  So I am convinced that energy can be extracted from (and fed back to) that quantum world.  And I think it is only a matter of time before there is adequate demonstration that we can retain some of that energy.

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I will join the discussion, but I might add that thermal methods are to be used when other methods become ambiguous or fuzzy.

Regarding whether PM's can do useful work, I believe it may be possible, but not the way most folks are doing it i.e using the springy push pull of magnets in attraction or repulsion or their force coupling or electrical induction methods.

If it is possible, I believe methods other than the above  need to be created and evaluated, as the above methods have been fairly well attempted by many tens of thousands of experimenters and proven to not work, or barely work such that they are  difficult to measure or demonstrate,AFAIK.

We use the term "useful" work and although magnets can exert a powerful force, you would expect that such a device, if possible, would also produce usable power in the range of hundreds of watts or more. We do not find this to be the case.


However, if you _move_ the magnets in the appropriate way in the appropriate system, you can produce usable power in the range of hundreds of watts or more. This usable power, though, comes from the means you used to move the magnets (or coils past magnets), like for instance the motion of an elevated mass of water through a turbine on its way to a lower position in a gravity field. These experiments have been done _many_ times and the energy input from the means of producing motion is always greater than the energy obtained at the output of the system. The difference is taken up by the inevitable losses due to friction, eddy currents, resistances and etc. and a careful accounting always shows _no_ energy provided by the magnets themselves.

Quote
Methods I would investigate if I had the time, would be a way to somehow releasing the energy used to create the alignments in the first place, and thus having a sort of solid state battery.

I'll repeat the same questions to you: Do you believe it is possible to extract _more_ energy from a PM than was used to magnetize it in the first place ("used to create the alignments" as you say)? If so, where does that energy come from? Does the magnet remain magnetized if you release the energy used to create the alignments in the first place?

Quote

Other method s I have contemplated would be along the lines of Smudge's work i.e somehow directly coupling to the aligned electron spins.

Another method would be to tap into an avalanche effect that may occur in soft iron Through an applied flux.

There are more, but all for now gotta run.
   

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Dear Smudge.

May I humbly remind you that you were going to provide us with a plan, this was some months back, another thread.

I would love to give your experiment a try as soon as I'm able.

Kind regards, Grum.

Mmm, yes, sorry about that.  Put it down to short term memory loss.  I am away from home (still!) with only occasional internet access but will get onto it when I get home.
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I am not talking about spinning magnets.  In the Marinov generator the magnets do not move.

Aspden pointed out that if you add the field from a magnet to the field from a coil you get a field energy related to the square of the sum field, and if you look carefully at the different components of (Bm + Bc)^2 you find the 2*Bm*Bc term that represents energy drawn from the magnet.  The energy is easily accounted for by considering the change in field from the initial magnet field Bm to the final field Bm+Bc.  That change creates the E field eddy that "loads" the atomic dipoles.  So I am convinced that energy can be extracted from (and fed back to) that quantum world.  And I think it is only a matter of time before there is adequate demonstration that we can retain some of that energy.

Smudge

So do you think that you can extract more energy from the magnet than was used to magnetize the material in the first place , which produced the initial magnet field Bm? If so where does this energy come from? Does the material itself change in some way when you extract it? Does it ionize, does it transmute to some other elemental composition, does it get all crumbly and fall apart? Lose weight maybe?

You can believe and postulate all kinds of things, but until you can perform some reliable experiment which _contradicts_ the results obtained from hundreds of years of experimentation, thousands of individual experiments, you are just believing and postulating.
   

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A lot going on in this thread, quite stimulating it is..

Magnetic hysteresis

https://en.wikipedia.org/wiki/Magnetic_hysteresis

When an external magnetic field is applied to a ferromagnetic material such as iron, the atomic dipoles align themselves with it. Even when the field is removed, part of the alignment will be retained: the material has become magnetized. Once magnetized, the magnet will stay magnetized indefinitely. To demagnetize it requires heat or a magnetic field in the opposite direction. This is the effect that provides the element of memory in a hard disk drive.

The relationship between field strength H and magnetization M is not linear in such materials. If a magnet is demagnetized (H=M=0) and the relationship between H and M is plotted for increasing levels of field strength, M follows the initial magnetization curve. This curve increases rapidly at first and then approaches an asymptote called magnetic saturation. If the magnetic field is now reduced monotonically, M follows a different curve. At zero field strength, the magnetization is offset from the origin by an amount called the remanence. If the H-M relationship is plotted for all strengths of applied magnetic field the result is a hysteresis loop called the main loop. The width of the middle section is twice the coercivity of the material.[17]

A closer look at a magnetization curve generally reveals a series of small, random jumps in magnetization called Barkhausen jumps. This effect is due to crystallographic defects such as dislocations.[18]

Magnetic hysteresis loops are not exclusive to materials with ferromagnetic ordering. Other magnetic orderings, such as spin glass ordering, also exhibit this phenomena.[19]


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A lot going on in this thread, quite stimulating it is..



Ah Yoda ..... Good to have you on board.   :)

So, who thinks that the Wesley Gary motor was a quaint fairy tale then?

Patents and the sale of working models for a " King's ransom " back in the day. True or false ?

This device would prove beyond any doubt IMHO that you can get work from a PM. And, for the umpteenth time one of our respected members here actually saw one working...... :o

Cheers Grum.


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Patents and the sale of working models for a " King's ransom " back in the day. True or false ?

This device would prove beyond any doubt IMHO that you can get work from a PM. And, for the umpteenth time one of our respected members here actually saw one working...... :o

Cheers Grum.

A respected member or not, third party information is hearsay at best, in the current information environment.. it is time this community understood this  C.C


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Quote from: Smudge
I am not talking about spinning magnets.  In the Marinov generator the magnets do not move.

It matters not whether the magnets move or not. Some power is applied to the rotating parts to keep them spinning at a given RPM, or, in the unpowered state, the rotating parts continue to move for a certain time after power is removed (spin-down time). In all cases, the power needed to keep the rotating parts spinning at a given RPM will be less when there are no magnets present, and greater when there are magnets present, and in all cases, the time it takes for the unpowered rotor to spin down from a given RPM to a stop will be longer when there are no magnets present, and shorter when there are magnets present.  (Of course the rotational MoI is equalized by replacing rotor magnets (if any) with equal weights in the "no-magnet" case.)

Feel free to specify exactly what "Marinov Generator" you are referring to, and design an experiment _with appropriate controls_ that could either falsify or support your experimental hypothesis. Which is what, by the way?  I've already given several experiments and controls which could be easily performed, with specified hypotheses.


A lot going on in this thread, quite stimulating it is..

Magnetic hysteresis

(etc.)


Hysteresis LOOPS, which begin and end at the same point. Think about that. You get back what you put in, minus losses which can be made very small. You _never_ get back more than you put in.
   

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Hysteresis LOOPS, which begin and end at the same point. Think about that. You get back what you put in, minus losses which can be made very small. You _never_ get back more than you put in.

In a closed system this is true.


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In watching ferro fluid march along flux lines it makes one think that the flux moves in its line(we know this) and that the fluid is being dragged along other than the fluid just attracted to a static line of force. When watching iron filings in oil move to a magnetic field the iron draws nearer the flux lines but also to the poles. Now this is where concentration is but its almost like there is something missing. All obviousness and idiocy aside we track the flux directions in cores so we have movement no matter where the flux is. Movement is work. Nothing profound here just needed to get some flux off my chest. Now I gotta get the flux outta here.


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And from the other thread:
You can do the measurement yourself if you are careful enough: The flywheel did not "create the energy", you stored the energy in the flywheel when you used some method to spin it up. The flywheel expends energy to move the PM's field to and from the coil, yes, and this results in the flywheel slowing down (or requiring more power to maintain speed). The energy put into the coil exactly equals the energy subtracted from the flywheel's motion (or the extra power put in to maintain speed) minus losses. The magnets participate only in the same way the hammer participates when you break rocks with it. The hammer doesn't "lose energy" when you break rocks, it only transfers energy from your arms to the rocks. Remove the hammer and nothing happens, you don't break rocks and _you don't get as tired_ from swinging your arms in the same way. Remove the magnets and you don't transfer energy to the coil and the flywheel takes longer to come to a stop, or requires less power to keep moving at the same speed.

You need to consider a complete cycle. There is "stored Magnetic Potential Energy" when you have the magnet separated from the steel, and this stored energy is returned when you approach closely enough. The complete cycle starts and ends in the same arrangement though. Start with the steel attached to the magnet, apply work to separate the two --- now you can see that you have stored energy in the arrangement "Magnet distant from steel". It is this work that is returned when you now allow the magnet to approach the steel and wind up with them stuck together again: a complete cycle, and the only work came from whatever means you used to separate them in the first place. Or start separated and finish separated again-- same thing. If you only look at half the cycle, you are ignoring the energy that is stored in the system in the first place. The same mistake is made wrt gravity by people who only consider half the cycle and ignore the storage of energy in the potential energy of height in the gravity field.

Er....  Do you think you can get more energy out of the magnet than was used to magnetize the bulk material in the first place, regardless of how much you have to spend to do it?
Where do you think that energy comes from? What changes when you extract it from the magnet? Does the material change in any way?

Yes TK I understand your points of view above, thats not really where I was coming from. A PM has stored energy and could be in an infinite form if it does not loose it's field strength, I'm talking PM, from the name perminent.

To be able to extract that stored energy, which you have stated it is stored energy, with less energy than you receive is what I think this is all about. Now if you say a super nova or the sun or any atomic power put the energy into the natural magnetic material on Earth, then you would of course be right, you would get less energy back, but it would be one hell of a storage means if it lasted for 1000yrs, even 10yrs until it died. Is not the earth one big storage magnet!! perhaps that is moving things a little way off course, and the world goes round and round ;)

Regards

Mike 8)


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TK said:

Quote
I'll repeat the same questions to you: Do you believe it is possible to extract _more_ energy from a PM than was used to magnetize it in the first place ("used to create the alignments" as you say)? If so, where does that energy come from? Does the magnet remain magnetized if you release the energy used to create the alignments in the first place?

The answer is: no to first question and no to the third, that's why I called it a solid state battery (if it could be done in the first place). The second question is then not applicable.

Actually my views are quite in alignment with your views, TK, with the only exception that there may be undiscovered methods that might be able to extract energy from the spins e.g. Smudge's proposal, which is not not yet fully explored, or other methods, not yet even dreamed of.

To reiterate, I do not believe permanent magnets can do work as typically applied, but we should remain open to possibilities for other  methods not yet attempted that fall in the category "atypical" that could yield some degree of success.

A lot of confusion comes from thinking that because something increases the efficiency of a system, that it actually performs useful work. e.g

The return magnetic soft steel path in a PM motor increases the efficiency of the motor, but cannot be said in itself to perform "useful work".

Higher compression  can increase  an engine's  HP output (when used with the right higher octane fuel). Is the energy coming from the increased compression ? no, it is just a engineered effect in a system which processes a fuel.

By extension permanent magnets are part of a system that processes electrical energy, turning it into mechanical energy.. In this application the PMagnets do not provide the energy, it is from the electrical input.

Another example, if you wound a motor with Nichrome wire instead of copper wire, you would see a decrease in efficiency, the energy wasted in heating the wire. Now go to copper and the efficiency increases. Is the copper wire responsible for doing useful work?

Regards, ION
« Last Edit: 2016-08-08, 22:54:15 by ION »


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TK said:

The answer is: no to first question and no to the third, that's why I called it a solid state battery (if it could be done in the first place). The second question is then not applicable.

Actually my views are quite in alignment with your views, TK, with the only exception that there may be undiscovered methods that might be able to extract energy from the spins e.g. Smudge's proposal, which is not not yet fully explored, or other methods, not yet even dreamed of.

To reiterate, I do not believe permanent magnets can do work as typically applied, but we should remain open to possibilities for other  methods not yet attempted that fall in the category "atypical" that could yield some degree of success.

A lot of confusion comes from thinking that because something increases the efficiency of a system, that it actually performs useful work. e.g

The return magnetic soft steel path in a PM motor increases the efficiency of the motor, but cannot be said in itself to perform "useful work".

Higher compression  can increase  an engine's  HP output (when used with the right higher octane fuel). Is the energy coming from the increased compression ? no, it is just a engineered effect in a system which processes a fuel.

By extension permanent magnets are part of a system that processes electrical energy, turning it into mechanical energy.. In this application the PMagnets do not provide the energy, it is from the electrical input.

Another example, if you wound a motor with Nichrome wire instead of copper wire, you would see a decrease in efficiency, the energy wasted in heating the wire. Now go to copper and the efficiency increases. Is the copper wire responsible for doing useful work?

Regards, ION

But what about the heat from the motor?.
What i mean to say is,if the PM field strength is increased,but the RPM of the motor,and the P/in to the motor are kept the same,by way of increasing the load on the motor,and that motor maintains the same heat output for a given power input,while at the same time the mechanical energy output rises--would that not mean that it was the increase in PM field strength that caused the increase in mechanical output energy?.

Per my test bed setup noted in m y first post
Expected outcome   :-\
Increase in PM field strength =
Same P/in
Same RPM
Same heat output from the motor it self
But an increase in mechanical output power-->which would result in a greater heat output from an eddy breaking system.

If the increase in PM strength only made the motor more efficient at converting heat waste into mechanical energy for a given P/in,then we should not see an increase in overall temperature from our DUT simply by increasing the strength of the stator PMs.


Brad


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But what about the heat from the motor?.
What i mean to say is,if the PM field strength is increased,but the RPM of the motor,and the P/in to the motor are kept the same,by way of increasing the load on the motor,and that motor maintains the same heat output for a given power input,while at the same time the mechanical energy output rises--would that not mean that it was the increase in PM field strength that caused the increase in mechanical output energy?.

Per my test bed setup noted in m y first post
Expected outcome   :-\
Increase in PM field strength =
Same P/in
Same RPM
Same heat output from the motor it self
But an increase in mechanical output power-->which would result in a greater heat output from an eddy breaking system.

If the increase in PM strength only made the motor more efficient at converting heat waste into mechanical energy for a given P/in,then we should not see an increase in overall temperature from our DUT simply by increasing the strength of the stator PMs.

Brad

By this line of reasoning you could start with weak magnets and keep doubling the strength expecting the motor efficiency to double each time, but we will find that we reach a limit as each doubling of magnet strength does not double the efficiency or we would wind up with 200% ...300% or more Pout than Pin.

 In Actuality, the system approaches but does not exceed 100% efficiency. As we improve the quality of the components of the system (more powerful magnets etc.) we reach the limit of efficiency that material science can provide, perhaps, in the future 99.9% efficient.

So in the ideal (lossless) 100% efficient motor we find  that the Pout of such a motor is not only directly related to the Pin, it is exactly equal to power in, so what do you think is actually doing the work?

Do you know of anyone that actually created an OU motor by increasing the magnet strength to the limits?
OK, even beyond the limits of magnet technology, is such a OU motor possible in a simulation where magnet strength is taken well beyond current practical limits?


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By this line of reasoning you could start with weak magnets and keep doubling the strength expecting the motor efficiency to double each time, but we will find that we reach a limit as each doubling of magnet strength does not double the efficiency or we would wind up with 200% ...300% or more Pout than Pin.

 In Actuality, the system approaches but does not exceed 100% efficiency. As we improve the quality of the components of the system (more powerful magnets etc.) we reach the limit of efficiency that material science can provide, perhaps, in the future 99.9% efficient.

So in the ideal (lossless) 100% efficient motor we find  that the Pout of such a motor is not only directly related to the Pin, it is exactly equal to power in, so what do you think is actually doing the work?

Do you know of anyone that actually created an OU motor by increasing the magnet strength to the limits?
OK, even beyond the limits of magnet technology, is such a OU motor possible in a simulation where magnet strength is taken well beyond current practical limits?

It may have been done,but i am unaware of any test done that accounts for total energy output,where heat energy is also included.

High end motors are getting close to 95% efficient-that is-converting electrical energy in to mechanical energy out,but leave out the generated waste heat energy. Are we to assume that under full rated load,that only 5% of the input power would be converted into waste heat energy?.
Lets say that our motor is under load,and it is consuming 100 watts of power. This would mean-even though the motor is working hard,only5 watts of that input power would be converted to waste heat--this i find hard to believe.

But lets get my test rig setup,and we will be able to see if the motors waste heat go's  down when we increase the PM field strength.


Brad


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