Search found 144 matches

by rnebel
Fri Feb 06, 2009 8:02 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

OK Art. I'm game. We don't know if the cusps are quasi-neutral. Use your theory and give me a quantitative prediction as to how the WB-7 will behave.
by rnebel
Fri Feb 06, 2009 6:23 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

Your logic is flawed. Ions do not have to move into the cusp at the same rate as electrons in order to maintain quasi-neutrality. If ions and electrons leave at the same rate that they enter (and this is true anywhere in the plasma) then quasi-neutrality can maintained. They simply have to leave at ...
by rnebel
Thu Feb 05, 2009 11:36 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

Electrons in both the Elmore-Tuck-Watson machine and the Polywell are formed at ground. Consequently, if they go back to ground there isn't a significant energy loss. The only way they can do this is if they are upscattered in energy. The major "cost" is that you have to have larger electron sources...
by rnebel
Thu Feb 05, 2009 6:00 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

Icarus:

What I think you can surmise from my comments is that confinement theories that rely on ambipolar arguments are incorrect. Polywells are not ambipolar devices for the reasons I stated above. Although some of the posters here may not agree with my comments, the WB-7 does.
by rnebel
Wed Feb 04, 2009 11:01 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

This is all very simple. In steady-state, ions and electrons leave the device at the rate they are injected. For closed field line systems like tokamaks, you have to inject neutral particles in order to get them across the magnetic field. This is generally a gas puff, frozen DT pellets, or neutral b...
by rnebel
Wed Feb 04, 2009 5:32 pm
Forum: News
Topic: Google Polywell Fusion Counter
Replies: 207
Views: 96581

People seem to be confusing quasi-neutrality with ambipolarity. They aren't the same thing, and one doesn't imply the other. Polywells are quasi-neutral. They aren't ambipolar.
by rnebel
Fri Dec 19, 2008 6:37 pm
Forum: News
Topic: MTF Illustration
Replies: 64
Views: 60820

This is basically LINUS revisited. LINUS was an experiment done at NRL in the 70s where a plasma was imploded with a liquid wall. I believe the plasma was a Z-Pinch. The idea behind MTF plasmas is that the magnetic fields provide thermal insulation, but not confinement forces which come from the lin...
by rnebel
Fri Oct 31, 2008 1:01 am
Forum: News
Topic: Found this during google search on Polywell Fusion
Replies: 55
Views: 160543

This isn't a big deal. This is small, interim funding. It's called staying alive until they make a decision.
by rnebel
Wed Oct 22, 2008 6:46 pm
Forum: Theory
Topic: EMC2's EIXL code and state-space modeling
Replies: 6
Views: 5532

EIXL is a 1.5-D Vlasov-Poisson equilibrium solver. The fact that it's Vlasov means that it doesn't have collisions. It assumes 1-D spherical potential wells. The .5-D is that it assumes finite angular momentum which is a conserved quantity. The fact that it is an equilibrium code generally means tha...
by rnebel
Sun Oct 19, 2008 10:03 pm
Forum: Theory
Topic: Central electron temperature and p-B11 power balance
Replies: 56
Views: 32987

I would say that the following is true: 1. P-11B is a very different beast to optimize than D-D or D-3He due to the Bremsstrahlung. 2. If all you had to do was to light the plasma against transport (and the theoretical scaling laws work) then one could get very large Qs from P-11B. This is the upper...
by rnebel
Fri Oct 17, 2008 9:24 pm
Forum: Theory
Topic: Central electron temperature and p-B11 power balance
Replies: 56
Views: 32987

Actually, you can get the energy differential back as well (though in practice it won't be 100%, I'm sure). What you do is keep the electron guns at a little higher potential than the wall which is at ground. In vacuum tubes they do this by having a small resistor between the e-guns and ground. You ...
by rnebel
Fri Oct 17, 2008 7:41 pm
Forum: Theory
Topic: Central electron temperature and p-B11 power balance
Replies: 56
Views: 32987

As near as I can tell, the arguments being made here are the same as those made by Rider many years ago. The problem is that you can’t study the polywell physics in isolation, you have to study the system as a whole. This is the mistake that Rider made and it appears to be the mistake that is being ...
by rnebel
Mon Oct 06, 2008 6:06 pm
Forum: General
Topic: Nuclear Power plant applications.
Replies: 21
Views: 12559

Olivier:
I believe that Pu239 decays into U235. I don't know this, but I suspect that's why the uranium content rises.
by rnebel
Mon Oct 06, 2008 5:58 pm
Forum: News
Topic: ITER vs the Stone Axe
Replies: 52
Views: 29059

JMC: First of all, let me reiterate that even though I’m not a big fan of ITER we’re not out to shut it down. The ITER people spent a long time building a consensus in the fusion program to build that machine and it wouldn’t be right for me to try to impose my opinions on them. If people want to wor...
by rnebel
Fri Oct 03, 2008 5:49 pm
Forum: News
Topic: ITER vs the Stone Axe
Replies: 52
Views: 29059

JMC: “As far as I've heard RFPs and spheromaks are horrendously unstable and so probably won't achieve ignition anyway.” This is another self-fulfilling prophecy which has been promoted by the people in the Tokamak community. In the late 80s Los Alamos was building a large RFP called ZT-H. It was ab...