questions about magnets

[Dr_Doggy]

hey,

I want to make a coil that can is the equivilant to one of those earth magnets, which coil would be best, and what kind of v&i?


also i was watching this:

https://www.youtube.com/watch?v=E97CYWlALEs

but my question is that: ok, so the eddies build and create opposing force, but then the eddies run out and the field colapses, right? how would we calc the period of that, wouldn't it be similar to a band (stop/pass) calculation?

(and bonus question: what would happen to a paramagnet in a superconducting field?)

 

[johansen]

the velocity at which the magnet falls is simply the amount of power dissipated in the copper when the current is created to fully support the magnet.

a quick look at Wikipedia shows that neodymium magnets are on the order of 100,000 amps per meter.
what this means is for a 7 cm long magnetic path, which is on the order of what you will find from a 1 inch diameter 1 inch long magnetic path is that you need to figure out how to pack 7000 ampere turns into a coil of wire 1 inch diameter and 1 inch long.

 

[Dr_Doggy]

7000 turns 1"x1" @ 1 amp is that correct? would i have a air core there?


about that first part though., i get what you are saying, kinda, but if we look at the tests;
https://www.youtube.com/watch?v=jyqOTJOJSoU&feature=fvsr
, the dimagnets only respond for an instant to the magnet, as oppose to 2 north poles which constantly push each other away, this i can only describe as a reactance frequency(maybe travel time for eddies?)
but is there a way to determine how long the dimagnet will respond to the magnet?
In a similar experiment they used a magnet to slow the drain of water in a bottle, but again as the eddies balance off and the water stops responding and drips out, my theory is that by replacing the magnet with a coil, I can invert the field causing the eddies to "reenergise", causing a more permanent plug, possible?

this is the closest thing i can find:
https://www.youtube.com/watch?v=8n5sSmJsCdY
now i know its not free energy as it states, but look at the principals he does use;

 

[Sceadwian]

What would be the point of all this? As has already been suggested the amount of power required to generate the magnetic fields involved are fantastically large.

The video of the Neodymium magnet setup in the router table is neat but incredibly dangerous! Given the mass of the wheel he made if any of those magnetic every crack and lose a piece the entire setup will explode very fast or at the very least rip the hell out of the table/motor setup and anything nearit. There's nothing 'free' going on here at all, it's nothing more than a mechanical induction heater.

If you directly applied the electrical energy to the copper pipe instead of the motor that drove the magnet ring the pipe wouldn't have just gotten warm and orange it would have melted within seconds, all he did in that video is find a Rube Goldberg contraption to waste more energy.

Neat but pointless. Things like this amaze most people, they're nothing more than parlor tricks though. I would personally like to see a wheel similar to what he built using much smaller magnets to increase frequency, but again it's dangerous and inefficient.

In theory you might be able to shape Diamagnetic materials with a structured applied magnetic field but it would be VERY weak use huge amount of energy. You'd need to find a use for it or it's just another parlor trick, these effects have been known about since before electricity was even understood, the tricks are getting a little more refined but they're still the same old tricks.

 

[Dr_Doggy]

i kknow it s not even close to free, but if i were to do that i'd use an ac coil, thats why im just wondering what is better to simulate that type of magnet, would a small coil with high current be better or a large coil with a small current??; i dont want to do that to copper but i do want to exploit the dimagnetic effect enough to create a pressure

actually i very much dislike pistons and other mechanical systems, it would be very handy to have a gas or liquid that i could evacuate using just a magnetic field, but there are obvious obstacles.

btw, im glad you said that about tricks, look at this one; i think he did it, you will see a clear acceleration, in the third one,, noone else was able to overcome that 360* position more than a few rotations even with a crank;
https://www.youtube.com/watch?v=zqG-TL0WnjE&feature=related

 

[Sceadwian]

but if i were to do that i'd use an ac coil

The question though is to DO WHAT?!

Nothing practical is done in those videos that can't be currently done using more conventional methods far more efficiently and practically.

The last video posted again there is nothing but tricks, nothing useful. the first example is nothing more than a magnetic only version of a spring, a real spring properly designed would put that to shame.

The rest of the bed tests are nothing my damping and harmonic spring effects mixed.

Nothing useful is done here other than come up with more complex methods of wasting energy. What do you think can actually be DONE?


People that do experiments like this waste massive amounts of time and energy and nothing practical comes out of it, not even greater understanding.

 

[Dr_Doggy]

i want to create a induction type pump that is able to form a pressure without any moving parts, just a tube and a coil, so that way i dont need to deal with pistons and such, or the noise of my compressor, which is why im reading in to this stuff.

i would also like to extend that in a second idea, to find a magnetic or superconductive way to push away a gaseous element or compound.

 

[Sceadwian]

A contactless magnetic induction pump?
If you're aiming for anything smaller than the size of 10x10 room that can pump anything more than a few ounces of fluid at a faction of a PSI pressure per our you'll never realize your goals.

You'd be better off researching the causes of noise in air/fluid systems and addressing the faults in the system or working with noise cancleation methods.

The concept is okay, but not the practical nature of any real world system.

 

[Dr_Doggy]

it doesnt need to be contactless, just no moving parts, except the gas/liquid of course

well in the copper cutting the guy is using a motor a few kw maybe? for a few seconds

so like we said using coils is better,
so if we had a coil to heat copper up to that temperature it would create a pressure, no? i get that induction is more expensive, but not that much,

or what if we used water as the core for an induction heater, the field would heat the water and force it out aswell, isnt that an additive bonus?

also again im not looking for free energy, but efficient although less than competitive methods,

likewise if i could use a superconductor to evacuate a gas, it would accomplish my goal aswell, but i don't know if ther is such a gas.

oxygen attracts to magnets, but does not repel diamagnets right?

 

[Sceadwian]

What exactly are you trying to do!?
If you need a vacuum you can generate it from a Bernoulli tube fed from a Venturi.

 

[Dr_Doggy]

yes a venturi, that is what im doing, but again i dont want conventional pump to do that cause of all the moving parts

 

[johansen]

it doesnt need to be contactless, just no moving parts, except the gas/liquid of course

well in the copper cutting the guy is using a motor a few kw maybe? for a few seconds

so like we said using coils is better,
so if we had a coil to heat copper up to that temperature it would create a pressure, no? i get that induction is more expensive, but not that much,

or what if we used water as the core for an induction heater, the field would heat the water and force it out aswell, isnt that an additive bonus?

also again im not looking for free energy, but efficient although less than competitive methods,

likewise if i could use a superconductor to evacuate a gas, it would accomplish my goal aswell, but i don't know if ther is such a gas.

oxygen attracts to magnets, but does not repel diamagnets right?

none of that made any sense to me.
you cannot heat a gas with EM unless you can get the field high enough to make plasma.
about the only way to heat water is microwaves, unless its conductive.

 

[Dr_Doggy]

or with convection from a material that does respond,

i actually want to use the em to create a flow, but not in the conventional way using spinning motors,

i thought about plasma-ing the gases but that is alot of energy, plus im not sure how much heat it creates,

my hypothesis was that if that guy can use the magnet machine there to heat copper,
and both copper and water are dimagnetic then shouldnt the water give us a similar response as the copper would? infact it would repel and expel in a magnetic field, which could be used in the venturi to form my pressure,

 

[johansen]

the water is dimagnetic but the copper is NOT heated because it is dimagnetic.
It is heated because there is electrical current flowing through it.
if the magnet were polished, and dropped down a thick steel pipe .001" diameter larger than the magnet, then the magnet would fall slowly as well providing sufficient lubrication.

 

[Sceadwian]

i actually want to use the em to create a flow, but not in the conventional way using spinning motors,

For what reason? Moving parts are what make water flow, you'll never get anything significant out of a solid state water pump, it would be pointless.

If you need a non-turbulent flow in the output all you need to do is use a higher powered pump to handle the back pressure that will be created and use something like felt filter bags over the output to produce a laminar flow.

The forces that magnetic fields can impose on diagmagnetic materials are so weak as to not be usable in any practical situation. It simply doesn't work that way.

 

[Dr_Doggy]

but wat about a superconductor, if it doesnt like magnetic fields then wouldnt it push even paramagnets, if it can support Fg of a magnet could that create a pressure? and dont all elements contain revolving electrons therefore magnetic domains, which would repel in a superconductor field, even if they do pair off and form a net0?

also i dont get that water copper thing, isnt it all eddie currents and resonant frequencies, iv seen water heat from microwaves, salt broken down with 12mhz RF, and the domains formed with ultrasonic standing waves, i cant help but feel that using the right freq you can manipulate other compounds, but how would i know which freq is best, even for heating copper? the copper only responds for a small time but how do i find how small that is?

also related but not, i have seen some guys using push/pull pistons and resonator cavities to get a chill, but how would i match it is it simple as having both cavities the same volume?

besides all that its verry hard for me to make an "airtight piston" ,\

actually this all came when i looked at doing a stirling engine, however i dont like how the pistons flap all around like that, i want to do something more centripital wher the diaphram spins so as not to knock as much(maybe combine it with the flywheel), also i want to make the power piston more inductive somehow, as to eliminate the knocking aswell, initally i thought of making the crank,cam,flywheel,and diaphram, all respond inductively somehow, the other thing i wantd to add was a way of using the stirlings output energy diirectly coupled as to produce a chill using another stirling cycle, and wrap it up with as few stages(parts) as possible!!

i have also read about those stirling acoustic horns, that i believe use water pressure, maybe i could utilize something like that to run my cooling cycle somehow...

 

[johansen]

but wat about a superconductor, if it doesnt like magnetic fields then wouldnt it push even paramagnets,.

nope, unless you can get up to about 100T or something.. (you need about 40T to levitate a frog)

 

[Sceadwian]

Try 16T Johansen.

but wat about a superconductor, if it doesnt like magnetic fields then wouldnt it push even paramagnets

There is no such thing as a 'paramagnet'. Paramagnetic materials are materials which respond to externally applied magnetic fields; super conductors do not naturally have any applied field associated with them so paramagnetic materials would not respond near a super conductor as there's no applied field to generate the paramagnetic effect.

The levitation experiments have nothing to do with superconductivity per say but with the strong magnetic fields that are created from the current loops that are set up in the super conducting material. It could in theory be done with regular conductors but the heating issues would likely vaporize the target and form a low energy plasma in the process

It might be worth noting that superconductors only exclude magnetic fields (depending on the material type) up to a certain magnetic density and then the magnetic field will actually cause the super conductor to stop super conducting, this is especially pronounced with higher temperature super conductors.

Water heating in a microwave has nothing whatsoever to do with a resonant effect, that is a much believed myth, microwave energy is absorb by a huge diversity of materials.

Basic materials outside of the quantum level don't have 'resonant' frequencies just absorption spectrums, water is pretty much only transparent near the visible region, in all other areas it absorbs very well.

This thread is going completely outside the realm of practical science with an extreme lack of understanding of the basic principles associated with the effects that are trying to be manipulated. I would strongly recommend coming back down to earth and doing some more research on the fundamentals before you continue.

 

[Dr_Doggy]

k sry, i may have gotten those confused, but after re-researching i found i want to make an induction heater,

i have seen those electric ones that use the high power, and prolly alot of $$
or maybe i could acheive the same , by doing like those guys spinning the magnets posted earlier, which seems to me to use less energy,

i am mostly curious about these heaters to heat metals but more importantly to reproduce the levitation effect as seen here....
https://www.youtube.com/watch?v=Q6Zrnv4OtbU
infact that s good since i can only go up to 2kw anyway on my outlet..

my biggest question though is what frequency do i operate at, should i just go with my coil reactance, i have a feeling that the globs have a certain requirement for frequency range,?

once again maybe it would be ideal to use lower voltages with higher currents and more turns on my coils?

 

[johansen]

**broken link removed**

^this is how i suggest you build such an induction heater.
all the H bridges need to be in sync and in phase.

if you use heatsinked IRFZ44/6/8 fets and you use 5 H bridges in series you should have enough headroom for operation directly off 120vac rectified line.

the power is varied by changing the frequency.

I don't suggest you build an H bridge designed to operate directly off 340vdc unless you've done that before.
the IRFZ44 fets should be good to 20 amps each, so you'll blow the circuit breaker before the mosfets explode.
they will share their current and voltage through the turns ratio of the transformers. all of which need to be identical.
you can use one transformer if you have 5 separate primaries of course, but keep in mind that there needs to be good insulation between the coils.

the work coil needs to be built out of appropriate material.
take a look at this:
**broken link removed**
and
**broken link removed**
**broken link removed**
in this example, the transformer is a crt yoke core, which is good for 1-2Kw easy at 120Khz.