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Modeling Polywell

Posted: Thu Mar 25, 2010 4:11 am
by JohnFul
In light of the lack of the ultimate model, the experiment, I am keenly interested in computational modeling of Polywell and the wiffleball effect. One start is the code presented in the link by D tibbets, http://www.mare.ee/indrek/ephi/images.pdf.

Interesting as it is, this is a model of conceptual perfection. I'm looking for a real world model that matches data as we know it. Preferably this can be broken down into components that can run on members of an HPC grid. Why you may ask? Because I just happen to personally have 24 cores with a total of 128GB of RAM and 14 TB of storage that I can apply to the problem. I'm running a virualized environment and can do whatever OS is convenient. My leaning is the Microsoft OS' but I am reasonably proficient in the Unix variants. In particular, I mainly work with BSD.

J

Posted: Thu Mar 25, 2010 3:41 pm
by KitemanSA
The recent 2009 IEC conference had an interesting paper regarding a PIC simulation of a polywell. That might be a place to start.

http://fti.neep.wisc.edu/iec2009/agenda

Posted: Thu Mar 25, 2010 7:28 pm
by TallDave
I corresponded with Joel Rogers the other day, he has an email list too if you're interested. Seems pretty open to adding people to it,

Re: Modeling Polywell

Posted: Thu Mar 25, 2010 7:32 pm
by Art Carlson
JohnFul wrote:I'm looking for a real world model that matches data as we know it.
Data?! You mean there is actual data somewhere?

Posted: Fri Mar 26, 2010 12:19 am
by Indrek
Lol

Posted: Fri Mar 26, 2010 12:36 am
by ckrucks
Indrek! Good to know you still lurk and post.
________
DURASPARK

Posted: Fri Mar 26, 2010 12:44 am
by rcain
hail Indrek :)
(any simulated data you would like to disclose?)

Posted: Fri Mar 26, 2010 9:38 pm
by kcdodd
I have been working on a pic code with cylindrical symmetry. I am currently in the process of adding dynamic EM solver, as well as diffusion. My original objective was to model a mirror machine. But I think it will be possible to get some good ideas for a polywell from a simple spindle cusp model, as the same basic principles are at work (point cusps, line cusps, and convex magnetic curvature). My time to work on it is limited but I will post updates as it progresses.

Posted: Fri Mar 26, 2010 11:01 pm
by MSimon
My understanding is that in a mirror machine you have to make them unfeasibly long to get net power.

No problem for a simulation except for run time.

Posted: Sat Mar 27, 2010 1:59 am
by kcdodd
Yes, it was more like the Maryland supersonically rotating machine. Well the trick is to get it to run on a PC isn't it, lol.

Posted: Sat Mar 27, 2010 2:18 am
by icarus
Well the trick is to get it to run on a PC isn't it, lol.
Heard that some people have had good success on a PC with CUDA, takes advantage of the GPU on your video card (also paralleled GPUs) ... model problems only so far, so PIC may not be suitable, might be an interesting sideline though.

http://en.wikipedia.org/wiki/CUDA

PS: Didn't happen to come across that super-conducting bag code that you wrote? Might take another look at adding in the electron sheath now I have time again ...

Posted: Sat Mar 27, 2010 10:10 pm
by hanelyp
I'm thinking a full up simulation of the polywell isn't practical. But we might still get useful results from simulations of specific effects. Such as electric well profile assuming an idealized spherical confinement of electrons. Or the particle energy profile given the electric well. Both of these simulations could make very good use of symmetry. Isolated cusp behavior would also be of interest.

Posted: Sat Mar 27, 2010 10:33 pm
by TallDave
FWIW, Joel told me he hasn't been able to simulate a WB yet. But Rick has seen it in action, so we know it happens.

Posted: Sat Mar 27, 2010 11:39 pm
by icarus
But Rick has seen it in action, so we know it happens.
Is that the official line or more of your privileged-insider third person hear-say? What did he actually say, and what did he actually measure to verify this? Thnx in advance for any info.

Posted: Sun Mar 28, 2010 2:10 pm
by TallDave
icarus wrote:
But Rick has seen it in action, so we know it happens.
Is that the official line or more of your privileged-insider third person hear-say? What did he actually say, and what did he actually measure to verify this? Thnx in advance for any info.
He posted somewhere here words more or less to the effect of "confinement is 1000x times better in WB mode so this is easy to see." I believe this means they see the current drop off dramatically as they approach beta=1.

I should hasten to add we don't really know the WB forms, in the scientific proof sense, because the data hasn't been released and the WB effect hasn't been replicated in labs across the world, but I'm trusting Rick's statement for purposes of speculating on the Internet about the position of this technology in the context of suggesting that Polywell modelling is difficult.