Can an exterior magnetic field be created using permanent magnet induction?

[Robin07]

I'm trying to make an interior rotating mangetic field that will induce electron flow in an encapsulated closed loop coil. What I'm constructing at this time (not finished yet) is a rotating (0 - 1600rpm+) neodymium permanet magnet setup in a Halbach Array assembly. I understand that inorder for the coil of wire to produce a field it must be changing, correct? A constant rotating field will not produce/induce the field desired. How can I produce changing electron flow in the coil? I suspect that once this is figured out, the coil will produce a field on the interior (between the coil and the Hallbac Array rotor) as well as the exterior of the coil assembly. The strongest "exterior" field is what I'm trying to create as well as, once the Halbach rotor has spun down to zero rpm there will be no magnetic field produced.

If my description is not clear, I'll try to draw what I'm doing but I'm pc graphicly challenged.

Thanks for all you help.

 

[berkeman]

Yeah, a clear drawing would help a lot.

 

[Robin07]

I'm in the process of posting a drawing, please be patient, I would like it to be as accurate as possible. I'm having some problems drawing it since the the unit is a sphere. Each view is similar to the other which may tend to confuse a mental visual picture.

Thanks for your patience

 

[Robin07]

Here is a picture of what I'm making see attached

This is a work in progress and any input would go a long way.

Thanks again guys

 

[xez]

Hmm.. I'm still not quite understanding
what you're trying to accomplish.
You talk about creating an exterior
magnetic field. In very PARTICULAR
circumstances flux is confined
almost exclusively in the interior of a
high permeability closed region (e.g
inside an magnetic 'shield' hunk of
iron/ferrite or in a ferromagnetic
toroid or so on; in such cases the magnitude of flux external to the
permeable shield can be insignificant,
the closed flux loops pass almost entierly
through the highly permeable regions
rather than exiting them.

If you have dipolar (N<---S) "bar magnets" the flux will exit the north
pole and eventually form a closed loop
returning to the south pole. More flux
will concentrate in the interior of high
permeability regions than elsewhere
along the loop. In general the field will
expand to fill all space to SOME extent
getting progressively weaker as one
goes further from the poles. The
response of magnetic materials to a field
can be highly NONLINEAR, but
electromagnetic/static magnetic effects
are basically LINEAR except where/when
non-linear materials transport the
field. Given the assumption of
linearity, the field from any ONE of your
dipole "bar magnets" can be sketched
and estimated independent of the
existence of any other of the bar
magnets in the multipolar array.
The resultant field at any point in space
in this linear assumption will simply
be the vector SUM of each of the fields
due to the individual field sources
(each individual bar magnet) acting
independently. So that may simplify
the first estimate of what the external
field will be -- just picture the field line
loops extending outward into all space
from a single bar magnet going from
its north to south pole with a rapid
diminishment of field intensity as the
distance from the poles increases.
Then realize that the fields from other
nearby poles will either diminish or
reinforce the field at a given point in space depending on whether the fields
from the other poles cancel or
reinforce at the point in space in question.

The winding's topology eludes me; you
draw it with a sinuous shape along a
circular band, and to me that looks like
it's something like a helical solenoid
wound around the path of a toroid.

Compact tightly wound toroidal
solenoids produce flux that's
concentrated fairly uniformly in the
area of their interiors and the magnitude of field they produce outside
of the interior of the torus's cross section
is very small (nearly nonexistant) if
the toroid is of a high permeability
material e.g. a ferromagnetic one.

If you have a closed loop of wire,
a changing magnetic field in the interior
of the loop will induce a changing EMF
of circuital voltage in the loop and the
EMF voltage will therefore create a current in the loop opposing the change
in external magnetic field through the
loop. One can imagine a single loop
'ring' and a single bar magnet next to
the loop; when the bar magnet and
wire ring loop are coaxial (the loop could
slide around the bar magnet; the
pole of the bar magnet pointing directly
into the interior of the loop), the bar
magnet's field passing through the loop
interior will be maximum. When
the bar magnet is perpendicular to the
loop effectively NONE of the flux from
the bar magnet will pass THROUGH
the hole in the loop, so in that orientation the flux through the loop will
be essentially zero. Rotate the loop
face with respect to the bar magnet's
pole face and you'll get varying degrees
of bar magnet flux penetrating the loop
depending on the angle between the
field and the loop's face as you go from
parallel to perpendicular.

Your ?toroidal solenoid? winding will
generate EMF accordingly to the
vector sum of the external flux that
passes through its windings' interior
from the external fields in its environment. It's not clear to me
what the point of the winding is, or
that the net flux enclosed by its path
will ever be significantly different than
zero since as you go around the circle
the vector sum of the bar magnet
fields look to be zero, assuming the
bar magnets are of uniform strength,
and geometry. I presume the couple
bar magnets you drew with double
heads "<--->" vs "<---" is just an error
of drafting and that they're just two
more that follow the obvious 90 degree
pattern of rotation. I further assume
that the bar magnets are of a constant
distance from the winding, the winding
is uniform geometrically, and all
materials in the toroid and between it
and the bar magnet poles are uniform.

If you want changing flux in the winding
you could seemingly just hook it up to
a power source that generates the right
current in the winding to create the
desired field strength in it. Being
a toroidal winding you'll get much less
field strength outside the torus than
within in, at least if it's wound tightly
so that the solenoidal / toroidal
approximation holds.

Finally, regardless of the ~ 2000
RPMs involved, many aspects of this
problem will seemingly behave
essentially identically as if the apparatus
was not in motion. To be precise,
magnetic fields and currents that vary
in space and time as slowly as a few
thousand cycles per second can be
accurately modeled by the mathematics
that assume the fields are just static
at any given moment and that no
strong high frequency dependent
effects will be relevant. Hence you
can use the magnetostatic and "DC"
approximations for the coil and the
bar magnets to estimate the fields that
exist in and around the apparatus at
any given moment. That would make
it relatively easy to use well known approximation equations of magnetic
field strengths due to coils and dipoles
to analyze the resultant external field
at any point in space due to such an
assembly of permanent magnets and
less so due to your coil depending on
the materials and geometry involved.

I'm sure you could even model it in
some magnetostatic or other kind of
mechano-magnetic modeling software,
though just getting approximate results
from equations by hand may prove to
be more illuminating with much less
investment in effort modeling the system.

What is this for, anyway?

 

[ice109]

i didn't read any of the above weirdly formatted post but here goes. first of all this is a sphere of magnet wire? i really can't understand what this thing is suppoed to be. draw an orthographic view

 

[Robin07]

First of all this is a sphere of magnet wire? i really can't understand what this thing is suppoed to be. draw an orthographic view

Yes this is a sphere of magnetic wire. To be more specific it's two half spheres connected together that house an interior PM array configured on a dual axis rotor. Orthographically the image on the left is the top view, the image on the right, since it is a sphere, can be the front and the side view.

 

[ice109]

i can't imagine how you would wrap the magnet wire around the sphere? what is the point of this? i think it will be very hard for you to get an external field considering toroids and solenoids have very negligible external fields.

 

[Robin07]

Hmm.. The resultant field at any point in space
in this linear assumption will simply
be the vector SUM of each of the fields
due to the individual field sources
(each individual bar magnet) acting
independently. ?

I will need to respond to your post in parts, I'm exceedingly busy, my appologies xez. I am under the understanding that a Hallbach Array augments the field on one side of the array essembly to the point that the opposite side is 50x weaker? If this is not the case than my electromagnetic induction exercise ball is in the toilet.

Thanks again for your comprehensive input to my post.

 

[ice109]

what is the point of this thing. why don't you just describe what effect you want.

 

[Robin07]

what is the point of this thing. why don't you just describe what effect you want.

I a nut shell... It is my understanding that... when a magnetic field is induced into a ferromagnetic close loop circuit, the opposing force that is created is allways equal and opposite in nature. So, the center Haullbach PM rotor inducing a current in the surrounding windings will create an opposing field between the rotor and the windings. Since the center rotor is now in motion the opposing force will enhance the internal spinning, reducing secondary input to keep the rotor spinning. It is my hope to be able to induce this surrounding magnetic field and utilize the exterior field for futher research in mobile and switchable (On and Off) magnetic fields that could be used for NDT or therapeutic porposes like a magnetic bracelet, EDS and so on.

 

[ice109]

I a nut shell... It is my understanding that... when a magnetic field is induced into a ferromagnetic close loop circuit, the opposing force that is created is allways equal and opposite in nature. So, the center Haullbach PM rotor inducing a current in the surrounding windings will create an opposing field between the rotor and the windings. Since the center rotor is now in motion the opposing force will enhance the internal spinning, reducing secondary input to keep the rotor spinning. It is my hope to be able to induce this surrounding magnetic field and utilize the exterior field for futher research in mobile and switchable (On and Off) magnetic fields that could be used for NDT or therapeutic porposes like a magnetic bracelet, EDS and so on.

it won't work. there will be no external field and the windings won't enhance the field, they'll oppose acting like brakes on the rotor.

 

[Robin07]

The winding's topology eludes me; you
draw it with a sinuous shape along a
circular band, and to me that looks like
it's something like a helical solenoid
wound around the path of a toroid.

The winding topology was drawn as a sinuous shape for reasons of ease of drawing. The intent is to have the closed loops, wire or high permeable ferromagnetic shims machined to accommodate the exterior sphere shape

Your ?toroidal solenoid? winding will
generate EMF accordingly to the
vector sum of the external flux that
passes through its windings' interior
from the external fields in its environment. It's not clear to me
what the point of the winding is.

The windings are to create an opposing field that was induced by the (what is allmost a monopole) halbauch array. But as you have mentioned the net exterior flux field will amount to near zero configured/designed as I have in the drawing provided.

If you want changing flux in the winding
you could seemingly just hook it up to
a power source that generates the right
current in the winding to create the
desired field strength in it.

An external power source is outside of the scope of the intended end goal, thanks anyway xez. The only external source that can be utilized is man-power, even if that man-power is aided by mechanical means.

I'm sure you could even model it in
some magnetostatic or other kind of
mechano-magnetic modeling software,
though just getting approximate results
from equations by hand may prove to
be more illuminating with much less
investment in effort modeling the system.

Do you have a recomendation re: software?

What is this for, anyway?

Primarily EDS

 

[ice109]

Primarily EDS

ElectroDermal Screening?

 

[Robin07]

ElectroDermal Screening?

electrodynamic suspension/ levitation

 

[xez]

I will need to respond to your post in parts, I'm exceedingly busy, my appologies xez. I am under the understanding that a Hallbach Array augments the field on one side of the array essembly to the point that the opposite side is 50x weaker? If this is not the case than my electromagnetic induction exercise ball is in the toilet.

Thanks again for your comprehensive input to my post.

Ok, I apologize for not initially understanding / visualizing
the bit about the Hallbach array's purpose and function / topology.

I believe your understanding of that is essentially correct, it
can generate a field that's oriented and enhanced
externally to such an properly constucted array.

http://en.wikipedia.org/wiki/Halbach_array
http://en.wikipedia.org/wiki/Halbach_cylinder

 

[xez]

I a nut shell... It is my understanding that... when a magnetic field is induced into a ferromagnetic close loop circuit, the opposing force that is created is allways equal and opposite in nature. So, the center Haullbach PM rotor inducing a current in the surrounding windings will create an opposing field between the rotor and the windings. Since the center rotor is now in motion the opposing force will enhance the internal spinning, reducing secondary input to keep the rotor spinning. It is my hope to be able to induce this surrounding magnetic field and utilize the exterior field for futher research in mobile and switchable (On and Off) magnetic fields that could be used for NDT or therapeutic porposes like a magnetic bracelet, EDS and so on.

Here are my thoughts relative to the above.
a) When the strength of a magnetic field changes so
that there's more or less flux through the space enclosed
in a conductive loop, a circuital EMF is induced in the loop
that causes an 'eddy current' flow around the loop.
The eddy current flow is such that the magnetic field
it generates opposes the CHANGE in the magnetic
flux through the conductive loop. So when the
exterior field increases, the current through the loop
wll tend to decrease the flux through the loop by
generating an opposed magnetic field that tends to
cancel the increase of the flux through the loop.
Conversely when the exterior field is decreasing the
flux through the enclosed loop, the induced eddy
current gives rise to a magnetic field that increases
the magnetic field through the loop, opposing the
diminishment of the enclosed flux. In all cases the
induced eddy current and its magnetic field will act
as a 'mechanical brake' on the relative motion of the
exterior magnet and the coil such that the field in the
eddy current loop/coil will tend to remain as it is
and resist mechanical motions that would cause the
flux through the loop to either increase or decrease.

b) Magnetic fields passing near permeable
not previously magnetized ferromagnetic materials will
cause an attraction between the magnetic field source
and the ferromagnetic material. The flux will be drawn
to pass more completely into / through the
highly permeable 'soft' ferromagnetic material and
so there will be attraction between the material and the
magnet source; a withdrawing magnet will be 'braked'
by this attraction whereas a magnet moving toward
highly permeable material will be accelerated toward
it by the greater attraction the closer it gets.

The way to enhance the spinning of a rotor with
permanent magnetic pole(s) is to cause an attraction
between the pole and space in front of the pole/rotor's
direction of travel, and/or cause a repulsion between
the pole and space behind the pole's / rotor's direction of
travel.

In common generality relating to permanent magnet
rotors it's not possible to use passively
induced eddy currents or static permeable materials to
cause net augmenting acceleration of a rotor in a
perpetual way; that'd lead to a 'perpetual motion'
or 'free energy' type of circumstance.

Of course as in a motor you can use dynamically
generated externally placed/forced magnetic fields to accelerate
or maintain the motion of a rotor, but that's not by
drawing power / field energy from the rotor to create
the accelerating fields augmenting the rotor's
continued motion.

As long as the net momentum / energy of a closed
system isn't changed (i.e. not self-increasing and
also not decreasing either) you can contrive ways
to alter the system / motion in arbitrary ways without
violating energy / momentum conservation laws,
though of course there may be other physics that
limit the facility / spontaneity of the system transitioning
from one equal energy state to another...

 

[xez]

I a nut shell... It is my understanding that... when a magnetic field is induced into a ferromagnetic close loop circuit, the opposing force that is created is allways equal and opposite in nature. So, the center Haullbach PM rotor inducing a current in the surrounding windings will create an opposing field between the rotor and the windings. Since the center rotor is now in motion the opposing force will enhance the internal spinning, reducing secondary input to keep the rotor spinning. It is my hope to be able to induce this surrounding magnetic field and utilize the exterior field for futher research in mobile and switchable (On and Off) magnetic fields that could be used for NDT or therapeutic porposes like a magnetic bracelet, EDS and so on.

There is no reason it's different to create an Hallbach
array with electromagnets than to create one with
permanent magnets. So to the extent you want a
pseudo-uniform switchable (on/off)
'monopolar' flux emerging from the exterior of a
cylinder or sphere, you can just directly build the array
in part or in whole with electromagnets and turn it
on or off as desired. The mechanical rotations and
external shell winding isn't (in this limited sense) needed.

 

[xez]

electrodynamic suspension/ levitation

Generally there are a few ways this can be done:

a) magnet pole repelling another similar magnet pole

b) magnet pole attracting a dissimilar magnet pole
(which may be a pole induced in a 'soft' ferromagnetic
substance by the presence of the first magnet)

c) magnet pole repelling a diamagnetic material; usually
this needs EXTREMELY strong magnets since most things
are only VERY weakly diamagnetic; superconductors being
one notable exception.

d) repulsion of an eddy current region by an increasing
magnetic field.

e) attraction of an eddy current region by an diminishing
magnetic field.

Generally these all need some kind of
spatial or electrical / mechanical stabilization to perform
any kind of stable levitation / suspension against gravity
and anything that'll perturb the system from rest.

As for modeling software for magneto static or
induction machines / motors.. hmm.. ANSYS emag or
ANSYS multiphysics, maybe. Be prepared for sticker
shock as to high prices, as well as to find that the act
of modeling a system is sometimes more complex and
time consuming than just building it or analyzing it by
thought / manual calculations.

The fact that you're talking about complex coil and machine
shapes as well as moving parts especially complicates
FEM type modeling efforts; it's possible, but not trivial.

 

[ice109]

why do you post like the tha xez, it is so annoying

 

[Robin07]

As long as the net momentum / energy of a closed
system isn't changed (i.e. not self-increasing and
also not decreasing either) you can contrive ways
to alter the system / motion in arbitrary ways without
violating energy / momentum conservation laws,
though of course there may be other physics that
limit the facility / spontaneity of the system transitioning
from one equal energy state to another...

I will respond to your previous post, prior to the post I'm responding to at this time. I just need to absorb it in parts and respond appropriately. Re: ice109. It can be some what over whelming but as far as I'm concerned We're all different.

Your concluding statement is what I'd like to address. "not self-increasing and also not decreasing". Would a switching, flow on/off of the current be considered as a change in state? If so the center pin that rides in the interior horizontal axis can be designed to have half of the pin be conductive, effectively closing the circuit and opening the circuit as it spins. The most basic motor works on that very principal. The upper hemisphere would then make contact when the lower hemisphere does not. A gyroscopic spin is achieved by the center pin riding in a guide that facilitates the rotation, meaning that the top half of the pin needs to ride on the upper half of the guide and the lower half rides/makes contact on the lower hemisphere.

 

[Robin07]

Generally these all need some kind of
spatial or electrical / mechanical stabilization to perform
any kind of stable levitation / suspension against gravity
and anything that'll perturb the system from rest.
.

The proposed energy input is man-powered be it through mechanical assistance or other means.

 

[mfescience]

i must say. you are on to something and i can see what you trying to do,,i just want to say continue try to find the way,, one more thing,, your drawing is interesting,,looks similar to a part of a bigger project i am working on, just i can't say much to help you without me giving to much away on my private project i been working on for years, so all i can say is keep at it,, you will find the way.. www.myspace.com/mfescience[/URL] if you have a look you understand why i can't say much to help you as i would like...

 

[Robin07]

i must say. you are on to something and i can see what you trying to do,,i just want to say continue try to find the way,, one more thing,, your drawing is interesting,,looks similar to a part of a bigger project i am working on, just i can't say much to help you without me giving to much away on my private project i been working on for years, so all i can say is keep at it,, you will find the way.. www.myspace.com/mfescience[/URL] if you have a look you understand why i can't say much to help you as i would like...[/QUOTE]

It's affirming that someone has recognized the direction that I'm pursuing.
Your "MySpace" link is invalid, can you assist? I as well have been working on this for several years now. xez has helped me a great deal in regards to the basic principals/laws that need to be factored in, there's still so much prototyping to do. Good luck with your project and I empathize that you are not able to give "It" away. But you must realize that we are in it to make life and living better. Electromagnetism, I understand to be one of the five natural principals of nature.

 

[xez]

I will respond to your previous post, prior to the post I'm responding to at this time. I just need to absorb it in parts and respond appropriately. Re: ice109. It can be some what over whelming but as far as I'm concerned We're all different.

Your concluding statement is what I'd like to address. "not self-increasing and also not decreasing". Would a switching, flow on/off of the current be considered as a change in state? If so the center pin that rides in the interior horizontal axis can be designed to have half of the pin be conductive, effectively closing the circuit and opening the circuit as it spins. The most basic motor works on that very principal. The upper hemisphere would then make contact when the lower hemisphere does not. A gyroscopic spin is achieved by the center pin riding in a guide that facilitates the rotation, meaning that the top half of the pin needs to ride on the upper half of the guide and the lower half rides/makes contact on the lower hemisphere.

Well, yes, switching a current on and off certainly does
change the system state and magnetic field. When there's
zero current there's zero magnetic field generated by the
current. So if you had an electromagnet at 12 o'clock,
and a circular plastic rotor with an iron blob attached to
the rotor at the 9 o'clock position you would create a motor
by energizing the electromagnet, attracting the iron blob
toward the electromagnet, causing the rotor to
begin to spin clockwise. If you turn off the current in
the electromagnet just exactly when the iron blob
has rotated to the 12'oclock position (and is as close as
possible to the attracting electromagnet), the rotor will
keep spinning (an object in motion keeps its present
state of motion until acted on by an external force).
When the iron blob passes the 6 o'clock position and
so is again moving toward the electromagnet you may
re-energize the electromagnet and again attract the
iron blob on the rotor toward the electromagnet,
accelerating the already spinning rotor for a while longer.
Repeat the process indefinitely and you have a simple
motor.

If you have a coil with current flowing there's a certain
amount of inductance and a certain amount of energy
stored in the magnetic field. You can interrupt the
current with a switch and that causes the current and
magnetic field to begin to go to zero. However the act
of interrupting a current in an inductor causes an EMF
(circuit voltage) which would tend to keep the previously
flowing current still flowing in the circuit. The EMF
from the energy in the collapsing magnetic field
causes some high voltages and possible sparks across
the opening switch contacts or circuitry; that's how
a 'flyback' transformer in a TV generates high voltage
pulses, and also why 'snubber' surge suppression
circuits are used in parallel to relay contacts when the
relay switches off current in magnetic / inductive circuits
since otherwise the electric arc energy from the sparks
induced by the collapsing magnetic field energy would
otherwise damage the contacts like little lightning
arc discharges.

As to the external world, the magnetic field will just
transition from whatever value it had to zero in an
abrupt way, and the changing magnetic field will have
whatever effects one may expect from any other changing/
decaying magnetic field on any external magnetic poles,
circuits, etc.

As above, switching magnetic field locations and strengths
in accordance with the motion of rotors is the basic way
any AC or DC or stepper motor works, so there's nothing
wrong with devising to make use of such a scheme for
motion control.

 

[Robin07]

xez: You never search to amaze me... Your last response gives me a sense of direction based on sound footing.

You mention a, for lack of better words, a returning to a zero point. Would I be wrong to interpret this as, When a collapse in an electromagnetic flux field occurs, this in-turn causes an energy out-put? If I'm understanding you correctly, energy is derived from the return to normal/zero point, the stable state in nature?

Thanks again xez:

Listen I need to source-out mechanical engineering and find out how I'm going to wrap wire around a half hemisphere. So, if I'm delayed in my return posts... you know were I'll be.

I'll be back...

 

[xez]

xez: You never search to amaze me... Your last response gives me a sense of direction based on sound footing.

You mention a, for lack of better words, a returning to a zero point. Would I be wrong to interpret this as, When a collapse in an electromagnetic flux field occurs, this in-turn causes an energy out-put? If I'm understanding you correctly, energy is derived from the return to normal/zero point, the stable state in nature?

Thanks again xez:

Listen I need to source-out mechanical engineering and find out how I'm going to wrap wire around a half hemisphere. So, if I'm delayed in my return posts... you know were I'll be.

I'll be back...

You're quite welcome; good luck.

As for the energy, it's stored in the magnetic field
itself, and when the current that's producing the field
decreases the energy tends to return to the source
opposing the decrease in current.

The energy stored in the magnetic field will
do work *somewhere* as it dissipates since energy
can't be created or destroyed; as I've alluded previously,
often that takes the form of generating arcs / voltage spikes
at the source circuit terminals if the source current is
abruptly disconnected, though of course it's just a magnetic
field that's changing (decreasing from X to zero)
at some somewhat rapid rate, so it'll induce whatever
EMFs and eddy currents it can in any conductors in the
area etc. etc.


The energy in a magnetic field
(in Joules per cubic meter) is:
B*B/(2*mu) or equivalently
0.5 * mu * H * H.
where (B) is the magnetic flux density in Teslas,
and (H) is the magnetic field intensity in Amperes/meter,
and (mu) is the permeability in Henrys/meter.

An inductor with inductance (L) in Henrys and
flowing current (I) in Amperes generates a magnetic
field with energy 0.5 * L * I * I in Joules.

The force on a current of (I) Amperes over a
distance length (l) meters moving through a
uniform magnetic field of intensity
(B) magnetic flux density in Teslas, is:
F (Force Newtons) = (B cross I * l).
Where of course the force will be maximum when the
current flows at right angles to the magnetic field lines,
and the direction of the force being given by the cross
product of I and B.

 

[mfescience]

thanks for metioning error in myspace.com

hi is me..thank you for metioning error in my space is actually
www.myspace.com/mfe_science i forgot the line in between,,,lol silli me..so are you geting any closer to your thing..??

 

[Robin07]

To follow this post; see Making domed/half sphere closed loop coils for EDS

https://www.physicsforums.com/showthread.php?t=175501

 

[nanobot_90]

hey,
i'm currently doing the IB course and have to write an extended essay, whihch around a 4000 word lab report
my topic in physics is which is more effective way of inducing current rotating the coil in the presence of a magnet or rotating a magnet in the presence of a coil.
can some1 please help me i have no idea how to perform the same

 

[Robin07]

I have found that it's much easyer to have the magnets do the moving. When you have the wire moving, the electrical connections needs to be adapted to alllow for that movement in one form or another and that ads more parts. If you have the magnets do the moving the wire can be stationary and a direct connection can then be realized.

 

[nanobot_90]

but i can't get a way through this,
what if i do rotate the coil and magnet one by one,
how will my experimental setup look like?
i at sea with this:S

 

[Robin07]

Nanobot, I must tell you that, The original post was a question about creating an exterior magnetic field around, what I now call a spherical coil. I can advise you in-regards to what I found is easyer to do. ie: move the magnets or move the wires. In my project both the magnet array is moving but the wire has limited movement.

I'm not able to design what your thinking because I just don't know what your out come should look like or how any of the parts relate to each other.

I would prefer if you stay in-keeping with the original post or post your question in the forum and have some one that has some more exprience in answering it.

Thanks