magrid configuration brainstorming

happyjack27 · Post by **happyjack27** » Mon Oct 11, 2010 5:48 pm

looks like tombo beat me to the punch on the single-coil symmetric designs. (page 5)

regard plugging the cusps, i'm not sure you undertand what i meant. you can plug the cusps without prohibiting recirculation. i mean by using coils orientated like in hanelyp's design on page 1. i.e. where the plane on which the coil lies intersects the origin. and for plugging a line cups, the coil would also be traverse to the line cusp (i.e. make an "x" with it).

happyjack27 · Post by **happyjack27** » Mon Oct 11, 2010 8:10 pm

here's an example of what i mean:

single-coil octahedral magrid with cusp disruption on line-cusps.

happyjack27 · Post by **happyjack27** » Mon Oct 11, 2010 10:37 pm

here's an interesting configuration. probably leaky as all hell, though. i filled in the plane of the magnet so you can see the orientation and relations better, and i drew a line coming out showing north. there are actually two topologically distinct configurations. flip the poles of any pair of opposite magnets and you get the other one.

if nothing else, it's certainly interesting to try to picture the magnetic field lines and recirculation trajectories

hanelyp · Post by **hanelyp** » Tue Oct 12, 2010 2:20 am

D Tibbets wrote: Electrostatic or magnetic plugging of the cusps was tried in various machines, including WB5. In short, they do not work. Anything that tends to confine the electrons better, tends to create large leaks for the ions. This frustrating result apparently helped Bussard to realize that recirculation was absolutly essential to any of these cusp designs, thus the realization that no closed box machine (magnets outside the vacuum vessel) could work, and thus the design of WB6.

Dan Tibbets

Electrostatic plugging was tried and found not to work. Auxiliary coils to turn short line like cusps into point cusps I can see working better. One configuration I'd like to see is 8 coils (rectified octahedron) around 6 coils (rectified cube) with the cusp points lined up, and the line like cusps oriented crosswise to each other. Real coils in each set matching virtual coils or the other.

happyjack27 · Post by **happyjack27** » Wed Oct 13, 2010 8:40 pm

i just realized that my crazy whacky six-coil design is just the cusp disruption coils on the single-coil octahedral magrid, above, with the octahedral magrid removed.

rjaypeters · Post by **rjaypeters** » Mon Oct 25, 2010 11:24 am

"Straight" Square 6, 7?:

Probably a lot less trouble to build than the "bowed" variety.

rjaypeters · Post by **rjaypeters** » Mon Oct 25, 2010 11:29 am

Tetrahedron:

rjaypeters · Post by **rjaypeters** » Tue Oct 26, 2010 1:22 pm

"Cubist" WB:

rjaypeters · Post by **rjaypeters** » Wed Oct 27, 2010 2:22 am

Dodecahedron:

rjaypeters · Post by **rjaypeters** » Wed Oct 27, 2010 4:47 pm

Truncated Icosahedron (bottom or back torii hidden for clarity):

Heaven help anyone who has to build a Polywell out of this!

happyjack27 · Post by **happyjack27** » Wed Oct 27, 2010 5:07 pm

rjaypeters wrote:Truncated Icosahedron (bottom or back torii hidden for clarity):

Heaven help anyone who has to build a Polywell out of this!

I believe Coruscant is powered by a multi-decameter polywell of this configuration.

rjaypeters · Post by **rjaypeters** » Wed Oct 27, 2010 6:33 pm

happyjack27 wrote:I believe Coruscant is powered by a multi-decameter polywell of this configuration.

Pity about the dozens of technicians we loose each week...

Randy · Post by **Randy** » Wed Oct 27, 2010 9:06 pm

rjaypeters wrote:
happyjack27 wrote:I believe Coruscant is powered by a multi-decameter polywell of this configuration.
Pity about the dozens of technicians we loose each week...

Hey Guys - Speaking of crazy ideas,

Last week I was watching a NASA TV show about the last shuttle mission (STS-133) scheduled for launch on Nov. 1, 2010.

They talked about a Japanese experiment that will be performed during the mission. The argument was that since the environment at the space station, in orbit 250 miles above earth, has a vacuum better than any vacuum achievable on earth with pumps, that they will open a special thermos bottle during a space-walk and expose it to the vacuum of space for several minutes. Then they will seal the bottle shut and return it to earth for experiments.

You’ve all heard of ideas to put solar collectors in orbit and to collect, convert and beam this energy to microwave receiving stations back on earth.

So, if they work, why not build some polywell systems in orbit? You would have the best and biggest vacuum chamber that you could ever dream of. You could make it as big as you wanted. You could achieve near cryogenic cooling temperatures of super-conducting magrid coils just by shading them. And you could convert the electrical energy to microwaves and beam them back to earth.

Is this idea too crazy? Or do you think it could work?

~Randy

D Tibbets · Post by **D Tibbets** » Wed Oct 27, 2010 10:11 pm

Concerning collecting vacuum in a bottle. If the bottle is pumped down as much as possible and baked out, before launch, I suspect they would otherwise need days of exposure before near maximum vacuum levels could be obtained. Out gassing is a problem even at vacuum levels much less demanding.

Superconducting coils could be kept cold, though probably not at liquid helium levels because in low Earth orbit there is a lot of infrared radiation from the Earth. That is why LEO infrared telescopes need liquid helium cooling. The Web Space Telescope (if it is ever built) will be ~ 1 million miles from earth, and there shading apparently will suffice. Keep in mind that you cannot completely shade a satellite. You have to have unshaded surfaces exposed to the cold of space to radiate away any heat, otherwise you have a solar oven.

Also, passive cooling can cool the coils, but cannot keep them cold when they are bombarded by x-rays, fast neutrals, and cross field transported hot electrons. I suspect Much more effort will be needed to carry away this excess heat, compared to the that needed for cooling a non operating reactor.

Dan Tibbets

rjaypeters · Post by **rjaypeters** » Thu Oct 28, 2010 2:26 am

Randy wrote:So, if they work, why not build some polywell systems in orbit? You would have the best and biggest vacuum chamber that you could ever dream of. ... And you could convert the electrical energy to microwaves and beam them back to earth.

Is this idea too crazy? Or do you think it could work?

~Randy

Despite D. Tibbet's caveats, the idea of a space-borne polywell has been thought of by the propeller heads who want to build them into interplanetary rockets. One of the big pluses was the copious vacuum.

Microwave beaming? An extremely not-crazy idea. Just watch where you point those things...