Search found 722 matches

by kcdodd
Tue Jun 24, 2008 5:46 am
Forum: Theory
Topic: What's Electron "pushback?"
Replies: 13
Views: 7453

One way of thinking about it is that even though you can ignore the paths where there is uniform density, when there is a gradient in density (ie the density changes along some direction) you have an imbalance of paths, so you can no longer ignore them. There is an effective overall current there wh...
by kcdodd
Mon Jun 23, 2008 7:16 pm
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

I thought obj was only a simple mesh formal
by kcdodd
Mon Jun 23, 2008 2:44 am
Forum: Theory
Topic: What's Electron "pushback?"
Replies: 13
Views: 7453

A moving electron can be viewed as a tiny current element, just as if it were traveling in a wire. And of course currents produce magnetic fields. The path of an electron in an external magnetic field becomes curved, and the curvature of the path is always such that the magnetic field produced by th...
by kcdodd
Mon Jun 23, 2008 12:35 am
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

As an update I have been doing debugging and continued making memory and speed optimization and I think its starting to get into a workable range. I need to come up with a file format to get the geometry and configuration into the simulation, and then output the results. I'm thinking of using vtk fo...
by kcdodd
Fri Jun 20, 2008 6:31 pm
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

I'm not using matlab for this one. I'm doing it in c++ for more control in general. But I just dont want to worry about distribution and networking and all that, at least for now anyway. It may be possible to do it but that will wait till after I know if what I'm doing will even give good results. I...
by kcdodd
Thu Jun 19, 2008 10:41 pm
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

Yeah, Its interpreted as relativistic momentum though, and the velocities for the forces etc are found using the momentum = gamma*m*v equation.

The units are not even square so I cant use direct indexing. I use a binary space partition tree to find the nearest neighbors.
by kcdodd
Thu Jun 19, 2008 8:56 pm
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

I'm running win2k with 1gb memory and 2ghz processor. its a few years old computer, lol. I've already made some changes, I think one thing is there was some memory fragmentation going on but I think I fixed that. Its currently using like 150mb of memory for every 100k simplices, which would be like ...
by kcdodd
Thu Jun 19, 2008 7:43 am
Forum: Theory
Topic: Vlasov Solver [work in progress]
Replies: 86
Views: 53376

Vlasov Solver [work in progress]

I just thought I would post an update on the solver I am working on. Even with adaptive mesh it is being difficult to get the memory usage into a workable range. The actual solver code has been done since I posted my introduction in the general forum, but that was apparently the easy part :(. I'm ha...
by kcdodd
Thu Jun 19, 2008 6:07 am
Forum: Theory
Topic: Carlson and Nebel
Replies: 108
Views: 82397

I think the introduction of heavy elements would just knock all the light ones out of the reaction area. The velocity of a iron atom would not change much compared to hydrogen, or even boron. And considering it would be at several times the energy I would think the lighter elements would gain so muc...
by kcdodd
Mon Jun 16, 2008 7:15 pm
Forum: Theory
Topic: Of Line Cusps
Replies: 39
Views: 21602

Ah, thank you for the link what a treasure trove :).
by kcdodd
Mon Jun 16, 2008 5:02 am
Forum: Theory
Topic: Ion Trajectories Through the Wiffle-Field
Replies: 18
Views: 10155

The idea is to have ions trapped in well created by the electrons which means injecting them inside coil structure. You are right, if you inject them outside then their KE is greater then the well and they'll just fly right through the machine out the other side. edit: I'm sorry, I think I know what...
by kcdodd
Mon Jun 16, 2008 3:48 am
Forum: Theory
Topic: Of Line Cusps
Replies: 39
Views: 21602

My question is on the side of how he arrived at that number for the size of the hole. The b-field would be fairly uniform along the cusp axis, so what is to limit how large the hole would get.
by kcdodd
Sun Jun 15, 2008 10:09 pm
Forum: Theory
Topic: Of Line Cusps
Replies: 39
Views: 21602

I am curious how he came to the 2x the gyro-radius figure, and I'm a bit confused about what he means exactly. Because if the electrons are on an escape trajectory they must be traveling at nearly parallel to the B-field, which means their gyro-radius is basically zero, no matter what the energy or ...
by kcdodd
Fri Jun 13, 2008 8:53 pm
Forum: Theory
Topic: Of Line Cusps
Replies: 39
Views: 21602

My understanding of the wiffleball effect is it does not "close" any cusp at all. The very center of the device without any electrons in it has zero magnetic components since all the faces cancel each other. However, it is just a point in the center where this happens. Any movement off the zero poin...
by kcdodd
Mon Jun 09, 2008 4:58 pm
Forum: General
Topic: The Military Sucks
Replies: 40
Views: 19316

Don't I remember a history channel episode where the air force already built a nuclear powered jet back in the cold war? I think they piped liquid sodium coolant directly to the jet engines which ran off the heat of the reactor. Of course they had to have a lead lined cockpit and irradiated the air ...