Hardware

rexxam62 · Post by **rexxam62** » Tue Sep 04, 2007 8:08 pm

MSimon wrote:
rexxam62 wrote:I had the impression POPS only worked in a Grid. Polywell is gridless. Remember?
The plasma has a natural frequency.

You can excite it by changing the well voltage slightly at the proper frequency. i.e. modulate the HV power supply.

Or it may be possible to modulate the electron beams to excite the frequency.

In fact we might even be able to excite it by modulating the magnetic fields. Although I'd prefer to avoid those drive problems.

Simon

What does the above mean? Will it work or not?

MSimon · Post by **MSimon** » Tue Sep 04, 2007 10:44 pm

Will it work?

Only experiments can tell us that.

It looks good enough to be worth some effort.

Keegan · Post by **Keegan** » Wed Sep 05, 2007 3:31 am

MSimon wrote:Or it may be possible to modulate the electron beams to excite the frequency.

In fact we might even be able to excite it by modulating the magnetic fields. Although I'd prefer to avoid those drive problems.

Simon

I bet the future polywells are going to have both. The B fields and E guns are both going to be modulated and are going to be harmonically synced. Think of a 4 cylinder internal combustion engine. The camshaft spins @ 1/4 the speed of the piston/crankshaft.

So ontop of the already complicated well simulations id like to add oscilatory B fields and E guns. I think i can smell some computer science guys already crapping their pants.

cuddihy · Post by **cuddihy** » Tue Oct 30, 2007 4:23 am

Keegan wrote:
MSimon wrote:Or it may be possible to modulate the electron beams to excite the frequency.

In fact we might even be able to excite it by modulating the magnetic fields. Although I'd prefer to avoid those drive problems.

Simon

I bet the future polywells are going to have both. The B fields and E guns are both going to be modulated and are going to be harmonically synced. Think of a 4 cylinder internal combustion engine. The camshaft spins @ 1/4 the speed of the piston/crankshaft.

So ontop of the already complicated well simulations id like to add oscilatory B fields and E guns. I think i can smell some computer science guys already crapping their pants.

What problem would this method solve? Or is it just for better performance?

MSimon · Post by **MSimon** » Tue Oct 30, 2007 6:06 am

Better performance for a given size machine.

Keegan · Post by **Keegan** » Tue Oct 30, 2007 9:35 am

Has anyone emailed or talked with the pops guys @ Los Alamos ?

Has anyone here got access to journals ? Theres some pops info out there that we dont have. It would be good for the community if we could find these.

J. Park, R.A. Nebel, S.M. Stange, and
S.K. Murali, “First experimental
confi rmation of periodically
oscillating plasma sphere (POPS)
oscillation,” submitted to Physical
Review Letters.

J. Park, R.A. Nebel, J.W.G. Rellergert,
and M.D. Sekora, “Experimental
studies of electrostatic confi nement
on the INS-e device,” Physics of
Plasmas 10, 3841 (2003).

R.A. Nebel, S.M. Stange, J. Park, J.M.
Taccetti, and C.E. Garcia, “Theoretical
and experimental studies of kinetic
equilibrium and stability in the
virtual cathode of the intense neutron
source (INS-e) device,” accepted for
publication in Physics of Plasmas.

MSimon · Post by **MSimon** » Tue Oct 30, 2007 4:10 pm

Let me just say that the POPS guys have contact with the project.

If you listen to Dr. B's last interview he alludes to POPS (not directly) as a way to reduce the size of the reactor. He envisioned that as a follow on to his experiments.

If the money is there it should be done concurrently.

Keegan · Post by **Keegan** » Wed Oct 31, 2007 7:22 am

I would really like to hear what those guys think of the polywell.

MSimon · Post by **MSimon** » Wed Oct 31, 2007 2:12 pm

A birdie told me they are very positive.

windmill · Post by **windmill** » Wed Oct 31, 2007 3:33 pm

From the cursory reading I've done on POPS, I thought power scales INVERESLY as the size, hence the reactor design consists of hundreds of small (cm-sized) reaction chambers oscillating in phase. Doesn't that directly oppose the Polywell power scaling law?
When I listened to the interview, Dr. Bussard's mention of the "18-wheeler" reactor reminded me of the ICC concept from his second patent. Are spherical electrostatic waves the same as POPS?

MSimon · Post by **MSimon** » Wed Oct 31, 2007 6:40 pm

windmill wrote:From the cursory reading I've done on POPS, I thought power scales INVERESLY as the size, hence the reactor design consists of hundreds of small (cm-sized) reaction chambers oscillating in phase. Doesn't that directly oppose the Polywell power scaling law?
When I listened to the interview, Dr. Bussard's mention of the "18-wheeler" reactor reminded me of the ICC concept from his second patent. Are spherical electrostatic waves the same as POPS?

I think so.

The use of POPS is a way to increase the reactivity. If POPS can increase reactivity by 10X reactor linear dimensions are cut in half.

A lot of things that were up til very recently thought to be steady state in IEC are now known to in fact be oscillators. It may be that enhancing the natural oscillations improves performance.

Experiments need to be done.

Keegan · Post by **Keegan** » Thu Nov 01, 2007 10:44 am

windmill wrote: Dr. Bussard's mention of the "18-wheeler"

I dont think this concept is viable at all, at least for some time. People see a cute little set of polywell coils. What they dont see is the power supply hardware. Its going to be a big heavy sucker.

"In using a harmonic oscillator analogy, the ion mass provides the inertia, whereas the curvature of potential well is equal to the coefficient of the restoring force." - Park.pdf

Gotta love the pops physics. It is very elegant. Correct me if im wrong but the ion cloud is an oscillator. The electron cloud is not. Was thinking about pops and the space charge of the core is going to have a big influence on it all.

MSimon · Post by **MSimon** » Thu Nov 01, 2007 12:32 pm

Keegan,

The frequencies are different. They should vary by the sqrt of the mass ratio and the sqrt of the charge ratio (for fully ionized particles). Lighter masses being higher frequency. Higher charges being higher frequency.

Inversely relative to reaction volume size.

It is all about velocity vs distance.

We have theory. However, experimental results are the real deal.

Keegan · Post by **Keegan** » Fri Nov 02, 2007 7:31 am

^ *nods* i concur

Inside the polywell the ion cloud can expand and compress with degrees of freedom. Thats Pops, its a harmonic oscillator, thats the easy part. The electron cloud however is bound by the magnetic cusps on one side and the ion core on the other. That means its got complex dynamics.

I would like to use electron cloud as a buffer ignoring its own resonant frequency. If lets say our ion cloud had a resonant frequency of 350khz. If we drove a 350khz radio wave into the machine i would hope that it would couple the energy through the electron cloud (like Newtons Cradle) to the ion cloud and POPS, you got your driven periodically oscillating plasma sphere.

So my thoughts, the ion cloud is exploited as a natural oscillator the electron cloud is not. Your right though, real experiments are the only way to solve this.
Dammit, i need a MaGrid more than i need a woman.

MSimon · Post by **MSimon** » Fri Nov 02, 2007 8:00 am

I know the feeling.

From what I have seen of the POPS literature the Q is moderate. It looked to be in the range of 2 to 20. SWAG.

With the electron cloud mass resonance at around 45X the proton resonance and at least a factor of 3X farther away from B11. Coupling between electrons and ions should be minimal. Then there is the gyro resonance of the moving electrons in a magnetic field. I really want a spectrum analyzer on that sucker.

It should also be possible to phase lock electrons and ions if that seemed like an advantage.

This is going to be one heck of a system when it all comes together.