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# Forget Oil - Contest: Find a substitute for oil.

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But I do believe it possible to build a machine which consumes only magnets (well the field generated by magnets) for fuel.

And of course when the magnets loose their magnetism they would have to be replaced so I guess it would litteraly consume magnets as well.

The problem with this approach is, as best I can tell, that demagnetizing a magnet – randomizing its constituent magnetic dipoles doesn’t produce energy, but consume it. Demagnetizing a magnet requires its many little dipoles to be twisted within its solid crystal matrix, which requires work/energy.

In principle, it should be possible to make an engine that takes, say, demagnetized iron, alnico, or a rare earth metal alloy, and generate energy as a by-product of magnetizing them.

Perhaps heating them to their Curie point, magnetize the material with a small magnetic field, then cool them, extracting more heat than was used to heat them?

Pretty complicated stuff, though, far beyond my skills of estimation or experimentation. :evil:

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The problem with this approach is, as best I can tell, that demagnetizing a magnet – randomizing its constituent magnetic dipoles doesn’t produce energy, but consume it. Demagnetizing a magnet requires its many little dipoles to be twisted within its solid crystal matrix, which requires work/energy.

The Idea is not to deliberately demagnetise magnets but to use their force to produce sustainable motion untill the (as it seems) inevitable happens: they become too weak to continue to produce motion.

Of course some magnets have longer life spans than others. For example cheapy refrigerator magnets only last a couple of years whilst speaker magnets seem to remain strong for years. I've heard rare earth (neodimimium) magnets are suseptible to failure caused by excessive heat and strong magnetic fields (the latter seams kind of silly to me seeing as they have quite strong fields of their own.)

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The Idea is not to deliberately demagnetise magnets but to use their force to produce sustainable motion untill the (as it seems) inevitable happens: they become too weak to continue to produce motion.
I don’t think that can work. The problem is that you’re assuming a strong magnet has more potential energy than a weak one, which, as best I understand it, is exactly the opposite of the physical reality.

Consider what happens in a simple arrangement like this, 2 permanent magnets, one fixed, one on an axle, like this:

$\unitlength 1mm \begin{picture}(100,20)(0,0) \put(0,15){\frame{\makebox(41,13)[lc]{N}}} \put(20,21.5){\circle{3}} \put(36,15){\makebox(5,13)[rc]{S}} \put(45,15){\frame{\makebox(41,13)[lc]{N}}} \put(81,15){\makebox(5,13)[rc]{S}} \end{picture}$

If 100% efficient (no frictional losses of any kind), set to rotating on its axle, this device would remain in motion indefinitely, neither gaining nor losing speed.

Each magnet is composed, essentially, of many small magnets, held in alignment, like this:

$\unitlength 1mm \begin{picture}(100,20)(0,0) \put(0,15){\frame{\makebox(41,13){}}} \put(1,16){\frame{\makebox(9,3)[lc]{n}}} \put(5,16){\makebox(5,3)[rc]{s}} \put(11,16){\frame{\makebox(9,3)[lc]{n}}} \put(15,16){\makebox(5,3)[rc]{s}} \put(21,16){\frame{\makebox(9,3)[lc]{n}}} \put(25,16){\makebox(5,3)[rc]{s}} \put(31,16){\frame{\makebox(9,3)[lc]{n}}} \put(35,16){\makebox(5,3)[rc]{s}} \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{n}}} \put(20,20){\makebox(5,3)[rc]{s}} \put(26,20){\frame{\makebox(9,3)[lc]{n}}} \put(30,20){\makebox(5,3)[rc]{s}} \put(1,24){\frame{\makebox(9,3)[lc]{n}}} \put(5,24){\makebox(5,3)[rc]{s}} \put(11,24){\frame{\makebox(9,3)[lc]{n}}} \put(15,24){\makebox(5,3)[rc]{s}} \put(21,24){\frame{\makebox(9,3)[lc]{n}}} \put(25,24){\makebox(5,3)[rc]{s}} \put(31,24){\frame{\makebox(9,3)[lc]{n}}} \put(35,24){\makebox(5,3)[rc]{s}} \end{picture}$

When a magnet looses strength (field flux), the many small magnets are rotated to no longer be as much in alignment, like this:

$\unitlength 1mm \begin{picture}(65,30)(0,0) \put(0,15){\frame{\makebox(41,13){}}} \put(1,16){\frame{\makebox(9,3)[lc]{n}}} \put(5,16){\makebox(5,3)[rc]{s}} \put(11,16){\frame{\makebox(9,3)[lc]{s}}} \put(15,16){\makebox(5,3)[rc]{n}} \put(21,16){\frame{\makebox(9,3)[lc]{n}}} \put(25,16){\makebox(5,3)[rc]{s}} \put(31,16){\frame{\makebox(9,3)[lc]{n}}} \put(35,16){\makebox(5,3)[rc]{s}} \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{n}}} \put(20,20){\makebox(5,3)[rc]{s}} \put(26,20){\frame{\makebox(9,3)[lc]{s}}} \put(30,20){\makebox(5,3)[rc]{n}} \put(1,24){\frame{\makebox(9,3)[lc]{n}}} \put(5,24){\makebox(5,3)[rc]{s}} \put(11,24){\frame{\makebox(9,3)[lc]{s}}} \put(15,24){\makebox(5,3)[rc]{n}} \put(21,24){\frame{\makebox(9,3)[lc]{s}}} \put(25,24){\makebox(5,3)[rc]{n}} \put(31,24){\frame{\makebox(9,3)[lc]{n}}} \put(35,24){\makebox(5,3)[rc]{s}} \end{picture}$

If you look at this last picture, you can see that it has a higher potential energy than the previous one. Rotating the little magnets to be misaligned – to have like poles facing one another – requires force applied over a distance, which is work. If this occurred because of magnetic and mechanical “jiggling” by the spinning device, the energy to do this work would have to have come from the kinetic energy of the spinning big magnet. So, even if all of the other mechanical parts are 100% efficient, the big magnet would lose speed and kinetic energy as the magnets lost strength, not gain it.

These are overly simplified drawing (the best I could manage using LaTeX :(). In reality, there would of course be many more little magnets, and they’d be at many angles, not always either exactly aligned or exactly reversed. Hopefully, they still communicate my points.

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So, even if all of the other mechanical parts are 100% efficient, the big magnet would lose speed and kinetic energy as the magnets lost strength, not gain it.

-CraigD

Yeah...

The Idea is not to deliberately demagnetise magnets but to use their force to produce sustainable motion untill the (as it seems) inevitable happens: they become too weak to continue to produce motion.

- D.D.

Also your schematic is incorrect....the arrangement in the first picture would rotate exactly as far as necessary for "N" on the fixed magnet to be aligned to "S" on the rotating one. (unless you used a flywheel or something like that...but it would probably still grind to a halt in fairly short order.)

Thinking bout it here it seems to me that another fixed magnet on the left side of the rotor aligned "S"-"N"* would allow this arrangement to go for a fair amount with a flywheel assisting.

*yielding "S"-"N" "A"-"B" "Y"-"Z"

"S"= south pole left fixed magnet "N"= north pole left fixed magnet

"A"=north pole rotating magnet "B"=south pole rotating magnet

"Y"=north pole right fixed magnet "Z"=south pole right fixed magnet

Like poles repell, opposite poles attract...that said the above layout should yield two push pulls per revolution.

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It seems to me that you still think I'm shooting for perpetual motion.

Yes the magnets will lose energy over time (weaken).:eek:

Yes the machine will slow down and stop eventually (due to the magnets weakening which is why I mentioned that it would need new ones in previous posts above):(

I don’t think that can work. The problem is that you’re assuming a strong magnet has more potential energy than a weak one, which, as best I understand it, is exactly the opposite of the physical reality.

-CraigD

You lost me....right here.....uh...sure.....o.k....kindly tell that to the magnets that keep falling off my fridge...While you're at it DON'T tell my shop's saftey officer or it's owner!!!!! The last thing I need is 5 tons of steel traveling overhead held up by weak lifting magnets!!!!!! :hyper:

Don't get me wrong but that one makes exactly no sence to me...of course I'm of the "get a bigger hammer" school of thought!:camera:

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It seems to me that you still think I'm shooting for perpetual motion.
I think I understand your basic idea, the use of permanent magnets as a sort of “fuel”. There’s nothing “perpetual motion-y” about this. As long as energy is being extracted from the magnet, it can at least in principle be used to do physical work – in other words, to power a motor.

The problem, as I see it, is that, like many others I’ve seen propose such a motor, you have the physics of a magnet exactly backwards. You’re assuming (perhaps because they’re more useful in devices like refrigerator magnets and electric motors?) that, a strong magnet contains more energy than a weak one. This is simply incorrect.

Consider the following very simple arrangement:

#1: $\unitlength 1mm \begin{picture}(65,30)(0,0) \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{n}}} \put(20.5,21.5){\circle{1}} \put(20,20){\makebox(5,3)[rc]{s}} \put(26,20){\frame{\makebox(9,3)[lc]{n}}} \put(30,20){\makebox(5,3)[rc]{s}} \end{picture}$

#2: $\unitlength 1mm \begin{picture}(65,30)(0,0) \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{s}}} \put(20.5,21.5){\circle{1}} \put(20,20){\makebox(5,3)[rc]{n}} \put(26,20){\frame{\makebox(9,3)[lc]{n}}} \put(30,20){\makebox(5,3)[rc]{s}} \end{picture}$

where the $\unitlength 1mm \put(20,21.5){\circle{1}}$ is a axle.

It should be clear that #2 contains more usable energy than #1. Attach a transmission to its axle, and as the middle magnet rotates so that it matches arrangement #1, force and work (AKA energy) can be had from it. Attach a transmission to #1, and nothing happens, no force, on work.

Now, consider the simplified pictures of a strong and a weakened magnet in post #20:

Strong magnet: $\unitlength 1mm \begin{picture}(65,30)(0,0) \put(0,15){\frame{\makebox(41,13){}}} \put(1,16){\frame{\makebox(9,3)[lc]{n}}} \put(5,16){\makebox(5,3)[rc]{s}} \put(11,16){\frame{\makebox(9,3)[lc]{n}}} \put(15,16){\makebox(5,3)[rc]{s}} \put(21,16){\frame{\makebox(9,3)[lc]{n}}} \put(25,16){\makebox(5,3)[rc]{s}} \put(31,16){\frame{\makebox(9,3)[lc]{n}}} \put(35,16){\makebox(5,3)[rc]{s}} \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{n}}} \put(20,20){\makebox(5,3)[rc]{s}} \put(26,20){\frame{\makebox(9,3)[lc]{n}}} \put(30,20){\makebox(5,3)[rc]{s}} \put(1,24){\frame{\makebox(9,3)[lc]{n}}} \put(5,24){\makebox(5,3)[rc]{s}} \put(11,24){\frame{\makebox(9,3)[lc]{n}}} \put(15,24){\makebox(5,3)[rc]{s}} \put(21,24){\frame{\makebox(9,3)[lc]{n}}} \put(25,24){\makebox(5,3)[rc]{s}} \put(31,24){\frame{\makebox(9,3)[lc]{n}}} \put(35,24){\makebox(5,3)[rc]{s}} \end{picture}$

Weak magnet: $\unitlength 1mm \begin{picture}(65,30)(0,0) \put(0,15){\frame{\makebox(41,13){}}} \put(1,16){\frame{\makebox(9,3)[lc]{n}}} \put(5,16){\makebox(5,3)[rc]{s}} \put(11,16){\frame{\makebox(9,3)[lc]{s}}} \put(15,16){\makebox(5,3)[rc]{n}} \put(21,16){\frame{\makebox(9,3)[lc]{n}}} \put(25,16){\makebox(5,3)[rc]{s}} \put(31,16){\frame{\makebox(9,3)[lc]{n}}} \put(35,16){\makebox(5,3)[rc]{s}} \put(6,20){\frame{\makebox(9,3)[lc]{n}}} \put(10,20){\makebox(5,3)[rc]{s}} \put(16,20){\frame{\makebox(9,3)[lc]{n}}} \put(20,20){\makebox(5,3)[rc]{s}} \put(26,20){\frame{\makebox(9,3)[lc]{s}}} \put(30,20){\makebox(5,3)[rc]{n}} \put(1,24){\frame{\makebox(9,3)[lc]{n}}} \put(5,24){\makebox(5,3)[rc]{s}} \put(11,24){\frame{\makebox(9,3)[lc]{s}}} \put(15,24){\makebox(5,3)[rc]{n}} \put(21,24){\frame{\makebox(9,3)[lc]{s}}} \put(25,24){\makebox(5,3)[rc]{n}} \put(31,24){\frame{\makebox(9,3)[lc]{n}}} \put(35,24){\makebox(5,3)[rc]{s}} \end{picture}$

The weak magnet is full of arrangement #2s, while the strong one is all #1s. So you can in principle (though not with anything so straightforward as an axle) get energy from the weak magnet (changing it into a strong one), but not by changing a strong magnet into a weak one.

Here’s another way to look at it: Consider a simple piston/cylinder arrangement, with the north pole of a magnet on the inner piston face, and the north pole of a magnet on the inner face of the cylinder head. As with an internal combustion engine, this arrangement can generate power only if the total work (force times distance) on the piston on its inward stroke is less than the total work on it in its outward stroke. For this to happen, the magnets must get stronger shortly after the piston reaches it closest approach to the cylinder head. This must happen, at least slightly, with each cycle of the cylinder. After some number of cycles, the magnets will be as strong as they possibly can be, and the engine will need “refueling” by discarding the strong magents and replacing them with weak ones.

Unfortunately, this isn’t what naturally happens when the same poles of 2 magnets are forced together. Rather, the opposing magnetic fields tend to rotate some of the little internal dipole magnets within each magnets, weakening them. So, for a motor that extracts energy from magnetic material (which can only be done by making them contain less energy, that is, by making them stronger), some tricky technique will be necessary. I’m not at all certain that such a technique is practically doable.

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Twould be far easier (and more productive) in the piston engine example (which seams strangely familliar) to implement a slide and cam arangement whereby a cam driven by the crankshaft slides a pair of magnets in a motion perpendicular to the motion of the "magnetic piston" yielding a pulling force on the up stroke and then pushing force on the down by sliding the appropriate magnet into position above the piston slightly BTDC on the upstroke.

I still don't see how weaker magnets would produce more mechanical force in this particular type of project. Sorry I just don't get it. It's.......counter-intuitive????

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I still don't see how weaker magnets would produce more mechanical force in this particular type of project
Force is not the most important concept here. Work is. To see this, it’s critical to understand the difference between force, work, and the net work of an engine.

Force is that which can give rise to acceleration of a body with mass: $F = m \times a$. Work is force applied to a body over a distance: $W = F \times d$. Work and energy are practically the same thing. Usually we consider energy to be the potential to do work. Though not necessary for this discussion, the term power means the rate at which work is done: $P = \frac{W}{t}$.

Net work of an engine is the usable work it can do via a repeatable cycle. The formula varies based on how the engine works, but for the simple pistons we’ve been describing, it’s: $W_{\mbox{net}} = W_{\mbox{out stroke}} - W_{\mbox{in stroke}}$. Note that “in” in previous examples have been literally placing the piston closer to the cylinder head, but that it doesn’t have to be, nor does the motion have to be piston-like (ie: it can be rotary, or any other motion). What’s important is that there’s a net difference between the work done in one “stroke” of the engines cycle and in another.

In a device made of permanent magnets, this isn’t the case. $W_{\mbox{out stroke}}$ always equals $W_{\mbox{in stroke}}$. $W_{\mbox{net}}$ is always zero. Worse, if the magnets become weaker as a result of doing work during the motor’s operation, $W_{\mbox{net}}$ is negative. Rather than a motor that gets useful work from magnets, you have a motor that requires work from an external power supply to add energy to magnets by “winding them up” by misaligning their internal magnetic dipoles, reducing their external field strength.

Sorry I just don't get it. It's.......counter-intuitive????
It is counter-intuitive. :)

We’re accustom to thinking of unused fuel, such as unburned gasoline/air, as analogous to unused full-strength manufactured permanent magnet, and used burned gas/air as analogous to a used magnet, which has lost some of its original strength (magnetic flux density). The analogy, however, is wrong. Gas/air has energy because of the potential energy in its chemical structure. Burning it releases energy, doing work. A brand new permanent magnet has less potential energy in its many magnetically aligned atoms acting as magnet dipoles than the same material magnetically “randomized” to produce a weaker external magnetic field.

This analogy might be useful: A full strength permanent magnet is like an unwound clock spring – you can’t get any work out of it that you don’t put into it. A weak magnet is like a partially wound clock spring – you can get work out of it, but when you do, it becomes unwound (analogous to a full strength magnet).

The analogy is very inexact: a magnet doesn’t necessarily become significantly disordered and lose strength (gaining potential energy) when work is put into it by applying a force to another magnetic object in its field, while with a clock spring, this potential energy is exactly the same thing as the mechanical work used to wind it, and gained when it unwinds. The point is that, like a clock spring “wants” to release its energy and become unwound, a magnetic material “wants” to release its energy and become magnetized.

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That's the whole point magnets do store and release energy...the trick is to sort out how to harness it....of particular interest to me is how they repell and attract each other...

I'm presently working with two designs one of which a reciprocator which alternately slides two magnets (one "N" side down one "N" side up) above a "piston" made from a third magnet (perpendicular to piston movement which should drive a crankshaft which should drive a cam which should actuate the magnets above

as well as a similar set below the "piston"...

As far as finances are concerned I get goodies when I can spare the cash

and it keeps me happy tinkering so even if I never get my designs to work at least I had fun so no real loss there.

As far as other peoples money, it's perfectly safe.....Unless I manage to make my designs work and make them practical (useful)....then I intend to get me some bucks...I can dream can't I?:)

Incidently...I wonder if the fella that came up with the origional temperature differential type engine was so easilly dismissed. (for lack of a better way of putting it)

Magnetic trains are pretty impressive. They are expensive, but if we got serious about building a new future, I am sure we could create something very impressive and functional. I think it is perferable to begin with a whole new city, built for the future. I think the best place to build this new city would be in Texas with the intent of connecting Canada and South America, and then east and west. There are great advantages to being a commerce hub, and the expense of a magnetic train, demands high usage.

Private transportation might be created along the same lines as the magnet train, with the energy source outside of the vechile.

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Magnetic trains are pretty impressive. They are expensive, but if we got serious about building a new future, I am sure we could create something very impressive and functional. …
I too like maglev trains. :eek2: In particular, I like LLNL/NASA’s Inductrack approach :) which has the potential to be less expensive than the rail and bed upgrades necessary to convert a convention rail line to high speed service (Like sections of the Washington DC to Boston “Acela” line). Unfortunately, maglev appears to me to be dominated of late by earlier starters in the business using, IMHO, greately inferior approaches. :( In particular, “Transrapid” has received the serious attention of many planners and governments, which I believe to be a technical and strategic mistake. What Transrapid and some other systems has in its favor is a fairly mature, ready-to-deliver system, while Inductrack remains only a little-developed prototype. :(

However, maglev trains are essentially just very improved suspension systems, allowing a train to travel safely at much increased speed. They’re not an alternative energy source, but rather a major new energy (usually electric) consumer. Since a large portion of electric power is generated by oil-burning power plants, they may actually increase, not decrease, demand for oil. They don’t necessarily improve energy efficiency, and, since they’re generally intended to provide very high speed service, typically are much less energy efficient than a conventional, low speed train.

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Single Acting Magnetomotor Reciprocating

(why the fudge did my colors change?!?!?!?!?!?!?:phones:)

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Above you find a overly simlplified scetch of what I've been trying to convey with text...please note that for whatever reason the pushrod from cam lobe(which is green) to "valve" magnet (for lack of a better word) is black in this image and blends with the flywheel...I don't know why but when I converted from corel to adobe illustrator to jpg (for whatever reason corell won't let me go straight to jpg). the pushrod which was yellow changed to black and the flywheel which was red also turned black.

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