## thread for segments files and parameters for simulation runs

Discuss how polywell fusion works; share theoretical questions and answers.

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rjaypeters
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Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA
happyjack27 wrote: still 2 minor imperfections which you'll see in the video (one is definetely 3rd coil)...so it's fine by me as is.
Yeah, but they still make me crazy. I'll look when I'm less tired. I probably introduced the second error by "fixing" the first coil. Judging from tonight's experience, they look like multi-millimeter size errors.

This is about the maximum size of the chain-link coils because of 3-D considerations: 1.111m dia. Standard coil dia. = 1.261m. Really squeezes the central volume.

Options: reduce coil dia., reduce casing dia. & move coils away from the central volume.

Probably the minimum coil dia. = 0.621m (one possible link shown) : Out.
"Aqaba! By Land!" T. E. Lawrence

R. Peters

rjaypeters
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Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA

Do the "links" become the primary confinement coils? BTW, they look like hanelyp's octahedron to me.

Diametral close approach of "links" across the central volume is 1.168m v. 2m for the traditional six coils. If you want an analysis to fit in the 1m radius rule, it'll have to expand a little.
"Aqaba! By Land!" T. E. Lawrence

R. Peters

rjaypeters
Posts: 869
Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA

Code: Select all

``````//-x, +y coil begins - 3 - changed 20 Dec 2010 checked by spreadsheet
24
-0.742, 0.512, 0.433, -0.684, 0.606, 0.406
-0.684, 0.606, 0.406, -0.631, 0.691, 0.352
-0.631, 0.691, 0.352, -0.588, 0.761, 0.274
-0.588, 0.761, 0.274, -0.557, 0.812, 0.177
-0.557, 0.812, 0.177, -0.540, 0.839, 0.068
-0.540, 0.839, 0.068, -0.538, 0.842, -0.046
-0.538, 0.842, -0.046, -0.552, 0.819, -0.156
-0.552, 0.819, -0.156, -0.581, 0.773, -0.256
-0.581, 0.773, -0.256, -0.622, 0.706, -0.338
-0.622, 0.706, -0.338, -0.673, 0.624, -0.398
-0.673, 0.624, -0.398, -0.730, 0.531, -0.430
-0.730, 0.531, -0.430, -0.790, 0.435, -0.433
-0.790, 0.435, -0.433, -0.848, 0.341, -0.406
-0.848, 0.341, -0.406, -0.90, 0.256, -0.352
-0.90, 0.256, -0.352, -0.944, 0.186, -0.274
//was -0.90, 0.256, -0.352, -0.994, 0.186, -0.274
-0.944, 0.186, -0.274, -0.975, 0.135, -0.177
//was -0.994, 0.186, -0.274, -0.975, 0.135, -0.177
-0.975, 0.135, -0.177, -0.992, 0.108, -0.068
-0.992, 0.108, -0.068, -0.993, 0.105, 0.046
-0.993, 0.105, 0.046, -0.979, 0.128, 0.156
-0.979, 0.128, 0.156, -0.951, 0.174, 0.256
-0.951, 0.174, 0.256, -0.910, 0.240, 0.338
-0.910, 0.240, 0.338, -0.859, 0.323, 0.398
-0.859, 0.323, 0.398, -0.802, 0.415, 0.430
-0.802, 0.415, 0.430, -0.742, 0.512, 0.433
//-x, +y coil ends``````
Still can't find an error in the first coil of the dodecahedron, which makes me _very_ suspicious because I introduced it last night! So, now it's time to compare with my first submission of the dodecahedron, it should have the original, right?
"Aqaba! By Land!" T. E. Lawrence

R. Peters

happyjack27
Posts: 1438
Joined: Wed Jul 14, 2010 5:27 pm
rjaypeters wrote: Still can't find an error in the first coil of the dodecahedron, which makes me _very_ suspicious because I introduced it last night! So, now it's time to compare with my first submission of the dodecahedron, it should have the original, right?
your first coil is perfect. your third and one in the second half have an error. it's not important. i'll find it and fix it when i have the time.

the chain link, somewhere maybe about halfway inbetween the smallest and the largest seem right. the problem is figuring out the orienation (polarity) of the links. i'm not sure it's even possible to do it symmetrically on a wb-6 config. maybe on an inverse wb-6 or an octahedron?

and yes, they certainly took some inspiritial from hanelyp's in fact, i think i got the cusp disruptor idea from hanelyp's. they're just a second iteration of that.

as to do they ecome the main coils - they certainly become important. it looks like for medium sized ones they'd constant about half of the overall lorentz force contribution.

rjaypeters
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Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA
The coil mystery has deepened:

From the original coil #1 - the y coordinate 0.559 is relevant.
rjaypeters wrote:0.778, 0.454, -0.435, 0.718, 0.559, -0.426
0.718, 0.559, -0.426, 0.662, 0.641, -0.388
From last night, the y coordinate 0.550 is relevant.
rjaypeters wrote:0.778, 0.454, -0.435, 0.718, 0.550, -0.426
0.718, 0.550, -0.426, 0.662, 0.641, -0.388
The fun part is the simple spreadsheet I wrote this morning (to calculate distances between points) says the 0.559 is wrong and 0.550 is more likely right. Further, my design software reports, today, 0.550 is the correct value.

I implore you not to waste your valuable time on this mystery. I am satisfied...for now. As you say, this mystery is not significant to the work. And now I have another tool with which to check, which is a good thing.

I will look at a chain-link octahedron.
"Aqaba! By Land!" T. E. Lawrence

R. Peters

rjaypeters
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Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA
"Aqaba! By Land!" T. E. Lawrence

R. Peters

happyjack27
Posts: 1438
Joined: Wed Jul 14, 2010 5:27 pm

now i'm thinking though, in my sims most of the electrons are actually lost through the point cusps. not the quasi-line cusps. so maybe cusps disruptors at the point cusps? about the same size as these chain links, tangent to the coil plane or a little further out. orientated to maximize spherical symmetry as in this post (my Mon Oct 11, 2010 10:37 pm post)

rjaypeters
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Joined: Fri Aug 20, 2010 2:04 pm
Location: Summerville SC, USA
happyjack27 wrote:...cusps disruptors at the point cusps?
I'll be glad to model and then segment after you approve the mockup.

Will the current direction in the disruptors matter? Three "main" coil fields are "intersecting" around the point cusps.

I find this interesting:
happyjack27 wrote:...most of the electrons are actually lost through the point cusps
Tibbets' concepts have the fewest point cusps e.g. the four-coil only has two point cusps. While I'm working on the six-coil cusp disruptor, will you please simulate one of the Tibbets?
"Aqaba! By Land!" T. E. Lawrence

R. Peters

happyjack27
Posts: 1438
Joined: Wed Jul 14, 2010 5:27 pm
rjaypeters wrote:
happyjack27 wrote:...cusps disruptors at the point cusps?
I'll be glad to model and then segment after you approve the mockup.

Will the current direction in the disruptors matter? Three "main" coil fields are "intersecting" around the point cusps.
yes. because the plasma will see any asymmetries as field lines that just lead out and to infinity, and the electrons will all run out on those lines. so you've got to maximize spherical symmetry. beyond that it doesn't matter; it's all topologically equivalent so long as it has the same symmetries.
I find this interesting:
happyjack27 wrote:...most of the electrons are actually lost through the point cusps
Tibbets' concepts have the fewest point cusps e.g. the four-coil only has two point cusps. While I'm working on the six-coil cusp disruptor, will you please simulate one of the Tibbets?
point cusps matter, but on account of their size, not their number. fewer means larger so it'd actually be worse. more is better because it results in smaller, tighter cusps. and that's why the doedec confines so much better. i've run an octahedron (lower poly order than a wb-6) in my earlier sims and its easy to tell that its confinement is much worse.

i'm running more on the doedec. it seems to have much better confinement. i'm actually running a mxed particle without any "cheating" and it works great. i was just about to post that in the potential energy view, the electrons and ions seems to do a multi-modal spherical oscillation. i.e. it's not just a static potential energy well. it's a time-dependant potential energy _wave_. (quite possibly a superposition.) reminds me of how quantum physics suggests charged particles should move in the presence of a confining voltage field (i've been watching these videos to learn qp.) very interesting. i'm recording video.

happyjack27
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Joined: Wed Jul 14, 2010 5:27 pm
here's a clip of the oscillation of the e-field. note the x-axis is volume elements from the center (previously refered to as density normalized radius)

rjaypeters
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Location: Summerville SC, USA
I can think of three orientations for corner cusp disruptors which maintain "spherical" symmetry: vertical, inclined and random.

Vertical:

Inclined:

I haven't modeled a random orientation. I think the inclined is what you drew before.

The inclined coil has 0.866m diameter and is about 0.05m from the three coils.
"Aqaba! By Land!" T. E. Lawrence

R. Peters

happyjack27
Posts: 1438
Joined: Wed Jul 14, 2010 5:27 pm
[quote="rjaypeters"]
random won't work. the particles don't see the statistical expectation, they see the particular samples of the distribution that happens to be in the model.

they need to alternate everywhere. for instance, just the corners on top, should go vertical, inclined, vertical inclined, around the circle. and the bottom should be matched kitty-corner so that on any face it alternates. it should look the same on any face. (save a rotation about the axis through the face). then a line through the plane of the coil should go right through the center of the cusp.

i don't know how the polarity would work though. haven't thought about that. hopefully it _does_ work. like i said, asymmetry would be detrimental to confinement.

the cusps on the faces should be plugged with the 6 coils as shown in the brainstorming thread. those are the bigger cusps ones, so they're more important.

actually the corners are confusing because their alignment with the standard coils also has to be symmetric. just do the faces for now, that's simple enough.

happyjack27
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Joined: Wed Jul 14, 2010 5:27 pm
it'd also be interesting to see the plasma flow w/the disruptors _inside_ the main coils.

also keeping it simple, maybe just a smaller set of parallel concentric coils a bit further out (inscribing the same sphere) maybe about a 3rd of the radius?

rjaypeters
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Location: Summerville SC, USA
FWIW - Line cusp convertors:

Face cusp convertors:

0.484m minimum distance coil to coil, disrupter coil diameter = 0.866m

Keeping it simple means changing one thing at a time.
"Aqaba! By Land!" T. E. Lawrence

R. Peters

happyjack27
Posts: 1438
Joined: Wed Jul 14, 2010 5:27 pm
rjaypeters wrote: Face cusp convertors:
the cusp disruptors on the green axis need to be rotated 90 degrees for symmetry.