I wrote:Please clarify. Are the coils in icarus' sketches alternating or uni-directional?
And then
ladajo wrote:In WB6 & 7 the current flows are opposite in each adjacent coil.
To which I ask "are you talkin to me. Are you talkin to ME"?
Yes, I know that WB6, 7, and even 8 have been uni-directional, i.e., current in the same clock-wise direction, i.e., current in adjacent coils opposite at the point of nearest approach. But is that the case with icarus' sketches or are they supposed to be Randy's bow-legged octahedon style machine?
In WB6 & 7 the current flows are opposite in each adjacent coil.
So the current circulates around the all coils in the same direction relative to an external observer?
The magnetic fields need to be going in the same direction where the coils come closest. (In the centers out the lines, or vice versa, you'll need two right-hands to visualise it with curved fists and thumbs).
You could clutter the place up with endless questions, or you could just read carefully what is already there.
Me says:
For now, it is just a thought-piece. The currents all flow around the coils the same direction, i.e., central-cusp mag-fields all radially-directed identically.
Well, if icarus' magnets are all "north in" then this will have a lot of line cuspage, which Dr. B. seemed to want to avoid, to go along with the 8 point cusps. If it is Randy's bow-legged octahedron with alternating polarity, there will only be the 8 point cusps and 6 funny or X cusps.
try removing every other coil. i.e. all "north out" coils, since like you said adjacent coils in this are going in the same direction, the three neighboring edges of the "north in" coils will provide the necessary current for the "north out" field. then you get rid of those funky "saddle" cusps. while simplifying constructing and giving you more room to play around with the shape of the coils.
happyjack27 wrote:try removing every other coil. i.e. all "north out" coils, since like you said adjacent coils in this are going in the same direction, the three neighboring edges of the "north in" coils will provide the necessary current for the "north out" field. then you get rid of those funky "saddle" cusps. while simplifying constructing and giving you more room to play around with the shape of the coils.
Never thought about doing that. Good idea happyjack.
then if you want you can do a level-1 sierpinski gasket iteration on the faces (thus the former north in coils become 3 1/4-sized north-in coils with 1 1/4 sized north-out (virtual) coil in the center, and vice-versa for the north-out planes. giving you a 4x8 = 32-sided polyhedron.
I really think you want the corners NOT to be coplanar.
Which corners and co-planar with what? (There are at least two sets of curves that could be construed as 'corners').
I'll assume you mean the sharp corners of the coils and coplanar with the tangent pane of the generating sphere, where four of them come together .... and then ask why not?
If the corners of the coils are to close to a plane (relative to each other in this local area) the opposing magnetic fields that are compressed may be deformed into concave surfaces towards the center. That is why I mentioned not bringing the bowed corners to a plane, but to some shallow angle that compensates for theis magnetic field distortion. Making the axis longe in this demension might also be used. The illistration demonstrates this adustment. This is easy to do with the 4 grid design as there is only one axis through the top and bottom corner cusps. It would be more complex to manage withe the 3 corner axis present in the 8 grid design by icarus
Here is a better illustration of the 4 grid bowed magrid as modeled by rjaypeters. I hope he doesn't mind. This is copied from his private E-mail to me.
D Tibbets wrote:Here is a better illustration of the 4 grid bowed magrid as modeled by rjaypeters. I hope he doesn't mind.
Happy to be of service!
I'd be happy to model other good ideas also. I don't have any magnetic simulation software, but my CAD software does output in standard CAD formats, so I could collaborate with someone who doesn't want the tedium of the initial modeling.
P.S. A side project, I'm working on a dodecahedron, just for fun.
EDIT: Here are pictures referenced above.
Last edited by rjaypeters on Tue Oct 26, 2010 7:43 pm, edited 1 time in total.
in all the time he had, i wonder why Bussard himself didnt come up with a few more variations. though to be fair, perhaps he was focussng more on other parts of the problem space.
would be very interesting to model the mag fields and compare quantitavely with the original design.
in all the time he had, i wonder why Bussard himself didnt come up with a few more variations. though to be fair, perhaps he was focussng more on other parts of the problem space.
I do not believe that Dr. B would have liked this design as it has very long linear cusps and everything I've read by Dr. B suggests he thought linear cusps were bad. Indeed, HIS next unit would have had effectively NO linear cusps instead of the two-diameters worth of this design. (Oops, THREE diameters worth! )
But who knows. Try it and find out!
If someone has a big enough, good enough chamber and power supply, I'd be willing to wind a number of potential designs. I'm thinking about 30cm radius but only 16ish turns.
Anyone? Don't all answer at once!
Last edited by KitemanSA on Fri Oct 08, 2010 12:22 pm, edited 1 time in total.
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