Electrostatic/Magnetic Confinement Summary

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Electrostatic/Magnetic Confinement Summary

Postby csnyder » Mon Mar 28, 2011 2:35 pm

I didn't know quite where to post this link and I hope it is not a repeat of already well known information.

http://www.askmar.com/Fusion_files/Magnetic%20Electrostatic%20Plasma%20Confinement.pdf

I was searching for "plasma confinement" and ran across it. It appears to summarize a lot of the various ideas I have read about or thought about and put some numbers to the same. The paper is from 1993 with a dress-up in 2010 so some of its optimistic predictions may have already been proven wrong.

One of the interesting items (section 1.1.4) was a prediction that a fusor with a radius greater than 10 meters could make net power. I'm not quite ready to start on my 11 meter vacuum chamber but... Anyhow, I didn't find the term "lucky donkey" in the whole paper so I was quite pleased. (Fusor.Net visitors will understand the "lucky donkey" reference, anyone else should not lose any sleep over it.)

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Re: Electrostatic/Magnetic Confinement Summary

Postby Doug Coulter » Mon Mar 28, 2011 3:00 pm

An interesting paper to be sure. This is an ok place for it.

It seems there are a few "religions" in the fusion field, for lack of a better descriptor for it. I don't happen to belong to these particular ones in general, but that's me, and since my particular one hasn't yet saved the world, I feel like they are all worth pursuing - but with appropriate skepticism. All too often, proponents of one religion will seize on a tenet of another, try to combine them, and conveniently forget something important about the conditions under which this or that can hold true.

I call that the:
Step two -- a miracle occurs.
effect.

By simply failing to mention step two, a lot of religions get away with untruth via omission. Most often, even honest people miss it, and the honest ones at least realize what they've missed once you mention it, but like most flawed belief systems, the old junk still gets propagated by those with only slight knowledge -- and we all want to believe this can be done.

One issue for example is everyone's idea of "trajectories" or "recirculation". Particularly, the latter crowd goes on about that one, but never seem to be able to posit just how recirculation continues under losses that are always present -- I see the spring, I see the mass, I don't see the ongoing drive coming from either anything internal, or applied from outside -- and a tuned circuit is not a power oscillator! So -- I instantly toss all that out with a large grain of salt unless and until someone either mentions active drive, or some mechanism that can convert the incoming DC to AC (like some microwave tubes). Well, to tell the truth, before tossing it out -- I measured for it, and didn't find any. I'm a big believer in "why guess when you can know".

Confinement implies thermal conditions. The only people making any decent fusion doing that so far are the tokomak boys, and they sure have a nasty set of engineering problems to overcome even if they get it truly working. Confinement of a more or less neutral plasma seems to me to be a fairly futile exercise anyway, unless you have power over something neat like gravity that works on neutral things well. But again, that's just me. Their theories, heavily funded and backed up by serious simulations on super computers at great expense, predicted that they couldn't run higher currents than they were without serious instabilities. But you know -- not long after, some one did try higher currents and all the instabilities smoothed out! So much for those billions(!) wasted on theories. Wonder if they (or the Bussard crowd) ever noticed that electrons have a lot less mass than protons or deuterons, and if something is going to move due to the attraction of the other, it's going to be the lighter one....Doh! Frankly, I don't think a simulation has yet been done that even takes simple stuff like that into account correctly, and as a programmer I have some understanding why not -- it's not easy.

Since nearly all the losses are either plasma escape types of things, or electron interactions radiating photons, my own religion has to do with non-neutral conditions (just get rid of the electrons altogether) and control lower currents of pure ions, in a low loss technology -- similar to ion traps and accelerators where we already have proof the techniques work well.
We just have to change a few things -- in an ion trap, the ions are allowed to avoid collisions, and we want them, as one example. Chris has perhaps figured out a way to accomplish that, and we are awaiting results of his experiments. I have been trying some other things with mostly the same ideas in mind here, and again, we're awaiting more concrete results.

If you find something here, or in that paper that turns you on, our mutual hope is that you will build it and report on how well it works in a lab, vs how well some guy in an armchair with a theory and begging for money thinks it will work. I think there's plenty to go around, and don't necessarily urge people to follow the same path I happen to be on, as anyone knows, that changes pretty often depending on what I'm seeing in the lab with real particles, real gear, real measurements and only my poor self as a theorist -- I've lost faith in the others having proved them wrong so often and so consistently -- they don't seem to understand systems that can have emergent behavior (no one does, terribly well, until they do some real open minded study of said systems -- and we now have Internet routing algorithms based on ant behavior). It's a rocky road!

Hopefully you can draw from here and fusor.net and get something going -- anything. As it turns out, the elephant and tiger parts of this safari stew are pretty much the same for all approaches anyway, so building up for one will not result in a ton of duplicated effort should you decide to change course at some point -- you need all that stuff, and the hands on skills from working with it no matter what, and it's not so trivial to handle it all as just getting this and that from catalogs or surplus and firing it all up on a Saturday, unless you are insanely lucky.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Re: Electrostatic/Magnetic Confinement Summary

Postby Joe Jarski » Sun Apr 03, 2011 11:56 pm

Very interesting paper. It's a good summary of the many different methods being explored. And for an uneducated person like myself, it's encouraging that the first item in the conclusion is that IEC deserves some re-examination. While I don't have any expectations of being the "lucky donkey" with my retro approach, this excursion into physics has given me a whole new world to explore and learn new things. Searching the orchard for some low hanging fruit has an appeal all of it's own - not to mention that it's soooo much more fun to do stuff first hand instead of just reading and theorizing about it.

Everyone has their own ideas on how to make things work. Just as many times as I've tried to do something by a tried and true "formula" and failed, I've also been able make things work that supposedly shouldn't have. People tend to pick-up on different details and focus on what they view are the problem areas, sometimes loosing site of the big picture. The concept is simple, the real world is quite the opposite. I think Doug's ahead of the game with his massive amount of data acquisition equipment - if there's a "sweet spot" to be found, he's the most likely to see it instead of having it swept away in the noise.
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Re: Electrostatic/Magnetic Confinement Summary

Postby Doug Coulter » Mon Apr 04, 2011 11:40 am

Well, if it's true that I'm likely to find the good spots, it's as much as anything the fact that I'm deliberately, and painfully slowly, looking for them. I couldn't find where anyone else ever had, so it seemed like a fairly obvious way to move forward. More a function of discipline than brains in this case. That's why I'm building the data aq stuff -- I realized fairly early that even a very observant human just can't do it without some help.

What I'm seeing, and in hindsight it's pretty predictable, is that we have some fairly complex "emergent behavior" in what is a simple - appearing system. In other words, the simplicity is deceptive in this case, and most people who just model this in their heads (or in fancy software) don't manage to incorporate this fact. I am seeing zero that isn't pretty well explained by the standard model stuff here. But a lot is stuff that isn't predicted by it (because it's not good for predicting things like this, only explaining them post-facto).

An ant or honeybee is dumb. A swarm has behaviors that are more complex, due to the interactions of a bunch of "dumb" units. That's what we have here. The current laws of physics describe well what any single dumb unit will do when presented with these conditions of fields and so on. What it doesn't do very well is show you what would happen if you have a ton of things, in a field composed of the external one you apply, along with the fields they themselves create. If you knew were every single one was (and all other paramters, like the whole velocity vector etc), then you could compute the effect of all the other ions on the one you're looking at fine. But to then do that for each one as a function of all the others is frankly past the current state of the art for discrete time simulations -- in this case, the universe is it's own best model, and it runs in real time!

Hence the emphasis here on hands-on. We've seen the paper theories, and most don't adequately take this kind of thing into account, and don't handle well systems where the next input is the previous output (assuming you can quantize time well enough). If we waited for computer modeling to catch up, we might be waiting too long, but with hands-on work, there's always a chance of stumbling on some trick or symmetry that makes things work out like we want them to. Failing that, it seems our only way forward is to go with gear that automatically simplifies what we are trying to model, so the models can work. That's where I'm coming from with ideas like low current beam on beam (or other target) ideas -- simplification so we can get some more basic data we can then use to improve things.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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