Search found 144 matches

by rnebel
Thu Oct 02, 2008 5:45 pm
Forum: News
Topic: Dr Nebel and Long's current employment status?
Replies: 17
Views: 12945

The reason we haven't made any comments is that there isn't anything new to say. We're still waiting. We don't know how long it will take. Understand that the US governments fiscal year ended September 30th. People in the government have beeen busy. This is also an election year, and regardless of h...
by rnebel
Thu Oct 02, 2008 4:43 pm
Forum: News
Topic: ITER vs the Stone Axe
Replies: 52
Views: 29056

jmc "And I guarantee you, when another device is developed which is capable of economic fusion, they will utilize heat and fuelling technologies developed for ITER aswell as plasma facing materials and neutron shields developed by this programme." This isn't at all obvious, and I think you're wrong....
by rnebel
Thu Oct 02, 2008 4:23 pm
Forum: News
Topic: Dr Nebel and Long's current employment status?
Replies: 17
Views: 12945

We're still here.
by rnebel
Mon Sep 29, 2008 9:50 pm
Forum: Theory
Topic: Questions Once Again
Replies: 34
Views: 18186

Art: The idea is pretty simple. You oscillate the amplitude of the virtual cathode at the resonant transit frequency for the desired ion species you want to pump energy into. It selects species by q/m. For a harmonic oscillator potential, it's pretty trivial. It's described by Mathieu equations (dri...
by rnebel
Mon Sep 29, 2008 5:36 pm
Forum: Theory
Topic: Questions Once Again
Replies: 34
Views: 18186

Art:

Take a look at the POPS papers, particularly the Phys Rev Letter. Deuterium was removed from the well by resonantly heating it. The scheme is mass and charge selective.
by rnebel
Mon Sep 29, 2008 4:58 pm
Forum: Theory
Topic: Questions Once Again
Replies: 34
Views: 18186

Art et.al. We haven't been looking at direct conversion schemes. These were built by LLNL for continuum conversion in the 70s for mirrors. My recollection was that they got conversion efficiencies over 50%, but I might be wrong about that. I suspect that Ralph Moir knows the answer to your questions...
by rnebel
Mon Sep 29, 2008 4:06 pm
Forum: Theory
Topic: Questions Once Again
Replies: 34
Views: 18186

Why would you want to feed in ions and electrons at the same rate?
by rnebel
Sat Sep 27, 2008 8:55 pm
Forum: Theory
Topic: Further 'cheap' tests
Replies: 15
Views: 9043

Going smaller to check scaling usually isn't a real good idea. It usually gives you overly optimistic results. The concern is that as you go to higher field and larger size the dominant transport mechanism may change (the fastest mechanism always dominates) so going smaller may mask the limiting mec...
by rnebel
Fri Sep 26, 2008 4:54 pm
Forum: Theory
Topic: Fusors and p-B11
Replies: 22
Views: 11851

D-3He has been done in fusors (University of Wisconsin) and you can get grids that will handle high energy. Consequently, P-11B is also probably doable. The best material we have used for grids is a Tungsten-Rhenium alloy. Tungsten works at high temperatures and the Rhenium allows you to weld it wit...
by rnebel
Thu Sep 25, 2008 10:33 pm
Forum: General
Topic: Energy plans
Replies: 10
Views: 6863

jmc: Just because Jet hit Q ~ 1 doesn't mean that it is any closer to a practical fusion reactor than the Polywell is. If you want to use that criterion, then Los Alamos beat that a long, long time ago. Furthermore, if you can't make a practical reactor with D-T, then what is the point of the materi...
by rnebel
Thu Sep 25, 2008 4:14 pm
Forum: General
Topic: Energy plans
Replies: 10
Views: 6863

Jmc: Two points…. 1. The Tokamak isn’t any more “real” than the Polywell. Both of them produce thermonuclear grade plasmas and neither of them has been made into a reactor. 2. If a Polywell ends up having to be made enormous to beat transport losses, then we need to find a different concept. That’s ...
by rnebel
Wed Sep 24, 2008 5:17 pm
Forum: General
Topic: Energy plans
Replies: 10
Views: 6863

jmc:

If p-B11 works, 5 years isn't unrealistic. The engineering on these systems isn't all that bad. Getting away from D-T makes it a lot easier.
by rnebel
Wed Sep 24, 2008 4:57 pm
Forum: Design
Topic: dodecahedron
Replies: 36
Views: 22667

Colonel_Korg

The principle reaction is the alpha-11B reaction. Neutron energies are ~ 150 keV. Absorbing the neutron in boron produces a gamma, which also needs to be shielded.
by rnebel
Tue Sep 23, 2008 12:57 am
Forum: Design
Topic: dodecahedron
Replies: 36
Views: 22667

We've done the calculations. Neutron yield from a P-B11 Polywell machine (nonthermal) is about 1.0e12/sec. for a 100Mwe reactor. That's about 8 orders of magnitude less than a comparable D-T machine.
by rnebel
Tue Sep 23, 2008 12:41 am
Forum: News
Topic: ITER Costs Double
Replies: 34
Views: 18635

Josh:

I think that John Ahearne wrote an excellent article on this back in the late 80s or early 90s. I tried looking for it, but I haven't been able to find it. Ahearne used to be on the NRC. Regardless of how you feel about fission, it's a good read.