Confinement of a Conducting Wire

[mwemag]

I am trying to find out whether the following magnetic confinement could be realized:

Can a straight wire, while conducting current, magnetically be forced to stay in a certain position inside of an area surrounded by several permanent magnets, without being attracted to touch any of the magnets and without being able to escape the area between the magnets?

At first view the problem seems to be, that an arrangement of surrounding magnets would comprise several alternating pole directions and therefore exert not only repelling but also attracting forces on the wire, so the wire could still escape the surrounded area or adhere to a one of the magnets.

Thanks in advance.

 

[prex]

More information is required:
-is it necessary that the magnetic fields of the wire and that of the PMs interact normally? If not (unlikely I assume), you could use a shielded wire, provided the shield is ferromagnetic
-can you put the wire under tension?
-can you fill the space around the wire with an electrically insulating material (plastic)?

prex

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[mwemag]

Thanks prex

The field-interaction refers to an arrangement where the wire's axis is perpendicular to the field between two opposed magnetic poles (see attached diagram) or a similar geometry, but other configurations could also be used if possible.

Ferromagnetic shealding could only be done partially, e.g. a tubular shield surrounding the wire with at least a quarter part of the tube's cross section left open.

The wire cannot be put under tension by physical contacts, except magnetical, but the wire itself cannot be ferromagnetic.

The space surrounding the wire could be filled under the condition that there is still a small space left between the wire and the surroundng fill, no phyisical contact at the wire-fill interface.

The need to confine the wire is just to avoid physical contact with any surrounding element, except to the electrodes on the wire's ends. As long as there will be no undesirable contact, the wire could change it's position or even it's shape within the area surrounded by the magnets.

 

[prex]

Still don't understand your goal: can you better explain it and why you want the wire not leave its position?
Also don't understand why you cannot put the wire in tension (by using the electrodes): is the wire not straight?
But of course if you want to measure the force acting on the wire, then you need it to be fully unrestrained. So what?

prex

http://www.xcalcs.com

: Online engineering calculations

http://www.megamag.it

: Magnetic brakes for fun rides

http://www.levitans.com

: Air bearing pads

 

[mwemag]

The wire is liquid.
The goal is to keep a melted metal wire conducting current, but to avoid physical contact with the surrounding materials for thermal insulation reasons and to prevent material contamination. Therefore the need for magnetic levitation.

Shape changing or small shifts can be accepted, as long as the liquid wire won't touch the surrounding but maintains the contact to the electrodes.

First calculations show that the PM forces are strong enough to countervail against the fluid's gravity, liquid pressure and surface tension forces, thereby enabling to levitate and confine the fluid nearly in its initial cylindrical shape.

However the problem is rather the distribution of the field than its strength.

 

[prex]

So for you a 'straight wire' can also be a liquid vein? Amusing joke...
I suppose you know that magnetic levitation, meaning by this the use of a static magnetic field to raise by repulsion a magnetic object is an inherently unstable condition. If the object is a fluid I would say you are looking for troubles.
Your problem appears to me as an immensely complex one, you can't treat it by naive simple questions. You need to narrow down first all the constraints of the problem and describe them in a non ambiguous way.
BTW can you have the liquid cooling vertically down?

prex

http://www.xcalcs.com

: Online engineering calculations

http://www.megamag.it

: Magnetic brakes for fun rides

http://www.levitans.com

: Air bearing pads