Polywell particle simulation

Discuss the technical details of an "open source" community-driven design of a polywell reactor.

Moderators: tonybarry, MSimon

Post Reply
Johnb003
Posts: 2
Joined: Wed Jul 18, 2012 11:07 am

Polywell particle simulation

Post by Johnb003 »

I'm writing a particle simulation which I will make open source, designed to test electron confinement and see if I can reproduce the whiffle ball effect which chokes off the point cusp funnels.

I already wrote a version on the CPU that was really slow, and I'm porting to CUDA right now. I have all the math worked out so it's progressing pretty quickly, but it's still a WIP. I posted a video of my early results here:

http://www.youtube.com/watch?v=UfHXKUrb-as&hd=1

DeltaV
Posts: 2245
Joined: Mon Oct 12, 2009 5:05 am

Post by DeltaV »

You and happyjack27 need to coordinate/consolidate state variables, parameters and initial conditions, then both do runs for the same input vectors/time steps and compare results.

Without real lab data available, the more simulations the better.

Johnb003
Posts: 2
Joined: Wed Jul 18, 2012 11:07 am

Post by Johnb003 »

Good idea. I didn't know another person working on a simulation.
I will wait until I have my n-body interactions to collect data though.

vernes
Posts: 135
Joined: Tue May 13, 2008 10:22 am
Location: The Netherlands

Post by vernes »

work faster!

happyjack27
Posts: 1439
Joined: Wed Jul 14, 2010 5:27 pm

Post by happyjack27 »

i started out w/nvidia's n-body sample and modified it to do EM-calculations instead of gravity ones.

if you get stuck on anything, you can check my code on sourceforge:

https://sourceforge.net/projects/em-nbody/

the compute kernel is in "bodysystemcuda.cu":

http://em-nbody.svn.sourceforge.net/vie ... iew=markup

but be ware lest you copy any unknown bugs... more scientific to do it independantly.

i watched the video. looking good!

happyjack27
Posts: 1439
Joined: Wed Jul 14, 2010 5:27 pm

Post by happyjack27 »

oh, no n-body interactions yet.

that explains why the video was so much faster than mine and appeared to have different dynamics.

(whew! ...i thought i had done something wrong for a second, there!)

happyjack27
Posts: 1439
Joined: Wed Jul 14, 2010 5:27 pm

Post by happyjack27 »

also, you seem pretty smart and like you'd share my interests. if you want to check out an evil distraction, i came up with an idea that can possibly decrease the computational time complexity of n-body problems with only a small impact on accuracy. you can check out the basic idea here:

http://kevinspublicstuff.wikidot.com/petrock

it's sort of like going from a lagragian description to a multi-scalar eulerian description ( http://en.wikipedia.org/wiki/Lagrangian ... flow_field ) and back.

an advantage over a barnes-hut tree code is that due to the much more regular data access pattern, it scales a lot better on data-parallel processors.

i came up w/it when working on my swarm wars project ( https://sourceforge.net/projects/swarmwars/ ). i ran into a practical population limit due to n x n inter-organism interactions. but i needed the population size to be dynamic and practically unlimited. when i came up with the solution i thought it was an awesome idea. and could have practical implications for scientific modelling. i havent gotten around to fully implementing and testing it in swarm wars yet. (i've been doing some other improvements instead.)

happyjack27
Posts: 1439
Joined: Wed Jul 14, 2010 5:27 pm

Post by happyjack27 »

i just moved the above mentioned swarmwars over to github:

https://github.com/happyjack27/SwarmWars

i haven't been happy w/sourceforge. interface is kinda kludgy. (Though i'm not all to impressed w/github search and advertising features. kinda feels like i'm moving into a black hole.) might eventually move tsunami and em_nbody over there, too.

Post Reply