COMSOL simulation of a FUSOR?

It may be difficult to separate "theory" from "application," but let''s see if this helps facilitate the discussion.
User avatar
Werner Engel
Posts: 142
Joined: Sun Aug 18, 2013 3:51 pm
Real name: Werner Engel
Location: Vienna, Austria
Contact:

COMSOL simulation of a FUSOR?

Post by Werner Engel » Tue Sep 12, 2017 8:38 pm

Hi!

Has anyone tried to simulate the moving/colliding ions inside a fusor using COMSOL?

BR,
Werner

PS: Please also have a look at the Invitation to the "European Fusor Meeting" viewtopic.php?f=47&t=11622

Scott Moroch
Posts: 174
Joined: Thu Apr 26, 2012 12:48 am
Real name: Scott Moroch
Location: New Jersey

Re: COMSOL simulation of a FUSOR?

Post by Scott Moroch » Sun Sep 17, 2017 7:06 pm

Werner,

Several weeks ago I did simulations of ion motion in a fusor using Simion. I have been meaning to write a post on it but have been too busy with school. I have attached some pictures of the simulations. In each of these I launched ions in a circular distribution around the grid.

The left side of the picture shows the grid orientation, and the right shows the ion motion.

Scott Moroch
Attachments
IMG_1627.JPG
IMG_1626.JPG
IMG_1625.JPG
"In the middle of difficulty lies opportunity"
-Albert Einstein

ian_krase
Posts: 348
Joined: Mon Nov 28, 2016 7:48 am
Real name: Ian Krase

Re: COMSOL simulation of a FUSOR?

Post by ian_krase » Sun Sep 17, 2017 10:36 pm

Did you just buy SIMION,. Or did you have it from work or school?

Scott Moroch
Posts: 174
Joined: Thu Apr 26, 2012 12:48 am
Real name: Scott Moroch
Location: New Jersey

Re: COMSOL simulation of a FUSOR?

Post by Scott Moroch » Mon Sep 18, 2017 2:11 am

I am an undergrad at the University of Maryland and do research in the Radiation and Accelerator Facilities. I was given a copy of Simion for the research projects I am working on.

It is unfortunate that an indefinite license of Simion is around $800-$900.

Scott Moroch
"In the middle of difficulty lies opportunity"
-Albert Einstein

User avatar
Richard Hull
Site Admin
Posts: 10511
Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: COMSOL simulation of a FUSOR?

Post by Richard Hull » Mon Sep 18, 2017 4:09 am

Great stuff! As I do not have Simmon, what was the origin point of the ions? Can I assume the shell? Of course, this is the ideal in a fusor. Too bad the ions are born all over the volume in the common fusor with the vast majority never undergoing full acceleration, circulating in many smaller orbits.

Still, very interesting plots. Thanks for sharing.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Dan Knapp
Posts: 146
Joined: Wed Aug 06, 2008 12:34 pm
Real name: Dan Knapp

Re: COMSOL simulation of a FUSOR?

Post by Dan Knapp » Mon Sep 18, 2017 10:40 am

There is at least one ion optics software package, IBS, available free from sourceforge, http://ibsimu.sourceforge.net. I have never used it, but it might be worth looking into for someone who wants to do modeling and does not have access to SIMION.

User avatar
Noah C Hoppis
Posts: 56
Joined: Sat Dec 22, 2012 9:05 pm
Real name: Noah C Hoppis

Re: COMSOL simulation of a FUSOR?

Post by Noah C Hoppis » Sat Sep 23, 2017 5:07 pm

IBSimu is a very good option for ion source extractor and accelerator geometries. I've used it to poke around an ECR ion source extractor with good results. I'm not sure how well it would fair with spherical geometries allowing for orbitals. A "kill" function for prolonged life ions may be necessary.

I would be interested to see where and by which mechanism the bulk of ions in a fusor are produced (ion-neutral interactions, electron-neutral interactions, etc.).
"No missile ever flew before 10 pm"

User avatar
Richard Hull
Site Admin
Posts: 10511
Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: COMSOL simulation of a FUSOR?

Post by Richard Hull » Sat Sep 23, 2017 7:59 pm

I think we can go to the bank with the bulk of ions being produced by electron-neutral reactions via high field emission. The fusor is little different in operation from a fully controllable,
oddly electroded, neon glow lamp, partially functioning as a deuteron accelerator-collider for about .01% of its total modus operandi, producing only 1 billionth of its net applied energy in nuclear fusion energy. All the other 99.99% of the modus operandi taking place in the fusor simply heats the shell being given off as a net loss in waste heat, minus the microscopic amount of energy piercing the shell as 30kv+ x-radiation and flying 2.4mev fusion neutrons.

The above is a fairly good description of the functioning, average, amateur fusor.

In the long run, as a fusion reactor it is perhaps one of the most miserably wasteful sources of net applied energy to create fusion energy. Still, pound-for-pound and dollar-for-dollar spent compared to other fusion reactors, it is probably the easiest and least expensive fusion reactor to build and operate, making the production of real nuclear fusion a snap for the gifted amateur scientist.

The goings-on is a fusor are multi-modal; perhaps with 10 or 20 different modalities, (a witch's brew). Only 2 or 3 of these modalities are capable of doing fusion and these are the least functional of all the modalities. Of these least functional processes only the tinest fraction of their full function will ultimately produce fusion.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

ian_krase
Posts: 348
Joined: Mon Nov 28, 2016 7:48 am
Real name: Ian Krase

Re: COMSOL simulation of a FUSOR?

Post by ian_krase » Sat Sep 23, 2017 8:54 pm

How does this compare to a simple beam-on-target or colliding-beam-quasifusor system?

User avatar
Richard Hull
Site Admin
Posts: 10511
Joined: Fri Jun 15, 2001 1:44 pm
Real name: Richard Hull

Re: COMSOL simulation of a FUSOR?

Post by Richard Hull » Sat Sep 23, 2017 9:03 pm

Both of those are far more expensive and troulbesome to implement using the D-D process. While the best loaded target would be palladium, titanium seems to be the base material of choice due to expense.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Post Reply