With a Bigger Hammer...

[Richard Hester]

The University of Wisconsin has a fusor program focusing on the use of advanced fuels like D-3He, and eventually, 3He-3He. I believe at present they have the record for reaction rate in a simple fusor:

D-D 2.2 X 10^8 neutrons/sec @130 kV, 57 mA

D-3He 1.5 X 10^8 reactions/sec @ 115 kV, 34 mA

These are nice numbers for a simple fusor, but pretty miserable compared to the actual input power. A bigger hammer can only get you so far... A change in concept will most likely be necessary for a practical electrostatic fusion reactor.

[Jon Rosenstiel]

For D-D fusion the input power is over 7kW! Must have a pretty stout cathode! I wonder what their run times are?

Jon Rosenstiel

[Richard Hester]

They use a tungsten inner grid. Due to the fact that they use an aluminum vacuum chamber, they have a big x-ray problem, and operate in a concrete vault to avoid using up grad students too quickly...

[Richard Hull]

Love the humor, Richard.

Yes. At any voltage over about 60 KV most any vessel even molybdenum will get rather transparent. Fairly heroic efforts are demanded to keep operators safe in the effort.

I also agree that that's an awful big hammer. Still, their effective continuous operating power versus output neutron rate has got to be head and shoulders above the big fusion boys. Not to mention the vastly reduced price tag on anything they are using in the process.

Needless to say, if they converted to D-T the numbers could easily be 10e10 or 10e11n/s, I am sure. Colleges now would no more dream of allowing tritium on campus than titan missle silos. Lotta' admin assholes puckered up to the max out there when the word nuclear is mentioned in relation to students.

I mention a book in the REFS and BOOKS forum "Experimental Nucleonics". It is cheap and incredibly instructive in nuclear chemistry and isotope separation. It served as a standard textbook for years when colleges had every nuclide in the book on site given to them for the cost of shipping from Oak Ridge during the Atoms for Peace program (read as "Train Future Nuclear Bomb and Energy Techies") Every college worth its salt had or was building at least a swimming pool research reactor on site.

Oh well. Times and attitudes, they do change. I can't figure whether my generation was just fearless or ignorant or both. I do know that current thinking, teaching and experimentation is hobbled by a lot of rules and regs, scared researchers, scared administrators, scared politicians and a public that is knee-jerk frightened by media hype into a nearly cocoon like state of mental and emotional gridlock.

Richard Hull

[teslapark]

The nuclear department at my college has a "fusion research facility", but all the research is done on paper, mathematics and calculations.

Up until 1996 we had a research reactor. It was a 5 MW job, heavy water moderated, and was considered to be the best suited reactor in the world for researching Boron-Neutron Capture Therapy (radiation treatment for brain cancer).

This research, although planned, never took place because it was decided that the enriched fuel rods should be moved off location during the 1996 Olympics in Atlanta. This was referred to as a "non-routine maintenance." After the olympics were over, nuclear worry worts used the situation to make a case for shutting the reactor down entirely, which has since occured. I know that the nuke department used to have a large stock of hot samples as well, but I'm not for sure if even those remain now.

Adam Parker

[Adam Szendrey]

Hi!

Thank god the Budapest University of Technology here has a very nice working research reactor. The Central Phisycal Research Institute, has a few reactors one of them is also capable of electrical energy production in case of emergency.Since the reactor of the university is in the heart of the city, it is very safely built. And our little country also has a nuclear power plant...wow lol, the image at the bottom shows the reactor form the outside. Its a pressurized water system (there are 4 reactors each a small 400 MW unit) , not the huge 2000 MW russian type "boiler" , the type that blew into pieces in 1984. OKay im a bit off topic here sorry

Adam

[guest]

How many grad students do they use each run Richard?

[Richard Hester]

Doggone it, Wilbur, just when we get the little rascals trained, their hair starts falling out....

[DaveC]

Their miniscule "efficiency" is indication that most of the deuterons are not colliding. The collision cross section for a given KeV energy, can be viewed as a measure of the aiming accuracy required to score a direct hit which can cause a fusion reaction. (We all knew this, of course.)

This suggests the basic method of a couple open spherical grids ionizing low pressure D2 will not in general be very successful. As most everyone already knows, the vast majority of input energy (kV x mA) goes to heating the gas (thermal losses) and the grids and the fusor walls. Ultimately these losses limit the power input to the fusor, since the grids vaporize. You can get a feeling for the input power limits by estimating what power it takes to vaporize a length of the grid wire. The power balance equates input watts against radiated watts (stefan boltzmann relation) so that

I^2 R(T) = sA( Tgrid^4) , (ignoring the ambient temp)

For a 'electrically heated filament, input power increases in almost direct proportion to the voltage ( not as voltage squared) because the resistance of the filament is also increasing as its temperature rises.
The net effect is nearly all filaments burn out at the same currents...because the temps increase so rapidly approaching burnout. Thus tantalum, tungsten and other high temp metal handle more losses but only marginally so.

The key issue, seems to be improving the "hit ratio", the number of collisions/fusions per ion launched.

The preliminary trajectory data that I did a while back, shows that an electron (or ion) launched into the fusor sphere, can spiral around for hundreds of times before colliding with something. But the mean free path in the fusor must be very long (low pressure) for this to occur.

Depending on the initial trajectory of the particle, it is possible for it to completely miss the grids for many cycles. Maybe for all.

It should be obvious that ions which do not collide and fuse, will travel back out of the potential well at the center, loop around and return for another try, unless they hit a grid or other piece of structure.

However, the only times they can fuse, will be near the center when they have enough kinetic energy to approach closely enough for nuclear binding to occur.

( I assume here, the obvious condition that the ions must be injected at nearly zero energy though the outer wall , other wise they will collide with the wall after the first path)

This recirculating current is "99 and 44/100 percent" of the input current. If the fusor pressures are low enough for many passes to occur, AND if the trajectory is such that it avoids collisions with the grids or walls, then the probability of fusion increases in some sort of proportional way...

Perhaps you can see where I am going with this..... that by using lower pressures, and more finesse (focussed beams) in beam production, NOT higher voltages and more beam currents, the fusor efficiency should increase.

If something like 200 M degrees K is sufficient for the D-D reaction to occur, then we need only something like a 20 kV potentials. Colliding 20 kV deuterons will be at nearly 40 kV equivalent energy and a collision with a nearly stationary neutral D or D2 will also have sufficient energy.

So quite possibly,,, we should here be thinking of how to build Grid-LESS, LOW pressure, e gun and ion gun fusors.

Comments??

Dave Cooper

[Richard Hull]

Absolutely correct, of course. Ion gunned fusors are always superior. Gridless systems are the goal, but most here are still getting their feet wet. There is something envigorating about actually doing fusion which acts to stimulate further research and renewed effort in many people. Therefore, the simple fusor is a most valuable training ground just as was the demo fusor. It is all based on baby steps.

Plus, there is always that original post of mine in the Fusion powered future forum, "On to every parade a little rain must fall", that keeps nagging at me. It acts as a wakeup call, sending bad vibes regarding fusion in general.

Richard Hull

[DaveC]

Right you are Richard. We must usually walk before attempting to run. The gridded fusor design, provides a set of system benchmarks against which we can judge future progress.

I am beginning a study at work on involving electron guns, and will tuck in some efforts with heavier ion guns. I should be able to share the non proprietary parts... (rashly assuming we are THAT successful in finding anything really new about ion guns).

One thing that emerges from my post above, is that gated guns systems are quite promising here. Also, if both electrons and deuterons are launched together, they must be launched at voltages differing by the square root of the mass ratios, so that the velocities are reasonably similar.

Roughly working this out, ... for 20 keV Deuterons, the matching velocity for electrons is approximately sqrt(2x1836) =60 times lower. Thus 20 keV Deuterons will have the same velocity as about 333 volt electrons!!

To create a (more or less) charge neutral region in the poissor, ion and electron currents must be equal, but at different voltages.

This point wasn't clear to me before.

No doubt there is some more "rain" to fall on this parade... we shall see where.

Dave Cooper

[fusornator]

Hi Dave,
I came across this post while looking for all things that could be big; it looks like you wrote it 8 years ago Regarding this quagmire, and while I agree that high vacuum and ion guns are great, notable results Hirsch 1967 and pending some new results to be released this year IEEE.

Has anyone seen anything big? Like a 2m 200KV Fusor?
I ask this as there has been some scaling theory done in recent times but no one has actually built anything that I have seen.
The way I see it generally is that 2 types of scaling for increasing the reaction rate one is the better focus ion gun….
Two increase the reaction cross section and modest increasing density? One way this is often done is ramping up the power on the little fusor which like a light bulb burns out quicker…
To me it looks like there is ample evidence in the new work being done in last few years suggesting non linear fusion efficiency increase with size and the same time linear reduction in grid losses with increase in size?
So if you had the money would you try it?
I would appreciate any factual negative comments… and even more some positive ones.
Cheers,
Shon.

Dave Cooper wrote:
> Their miniscule "efficiency" is indication that most of the deuterons are not colliding. The collision cross section for a given KeV energy, can be viewed as a measure of the aiming accuracy required to score a direct hit which can cause a fusion reaction. (We all knew this, of course.)
>
> This suggests the basic method of a couple open spherical grids ionizing low pressure D2 will not in general be very successful. As most everyone already knows, the vast majority of input energy (kV x mA) goes to heating the gas (thermal losses) and the grids and the fusor walls. Ultimately these losses limit the power input to the fusor, since the grids vaporize. You can get a feeling for the input power limits by estimating what power it takes to vaporize a length of the grid wire. The power balance equates input watts against radiated watts (stefan boltzmann relation) so that
>
> I^2 R(T) = sA( Tgrid^4) , (ignoring the ambient temp)
>
> For a 'electrically heated filament, input power increases in almost direct proportion to the voltage ( not as voltage squared) because the resistance of the filament is also increasing as its temperature rises.
> The net effect is nearly all filaments burn out at the same currents...because the temps increase so rapidly approaching burnout. Thus tantalum, tungsten and other high temp metal handle more losses but only marginally so.
>
> The key issue, seems to be improving the "hit ratio", the number of collisions/fusions per ion launched.
>
> The preliminary trajectory data that I did a while back, shows that an electron (or ion) launched into the fusor sphere, can spiral around for hundreds of times before colliding with something. But the mean free path in the fusor must be very long (low pressure) for this to occur.
>
> Depending on the initial trajectory of the particle, it is possible for it to completely miss the grids for many cycles. Maybe for all.
>
> It should be obvious that ions which do not collide and fuse, will travel back out of the potential well at the center, loop around and return for another try, unless they hit a grid or other piece of structure.
>
> However, the only times they can fuse, will be near the center when they have enough kinetic energy to approach closely enough for nuclear binding to occur.
>
> ( I assume here, the obvious condition that the ions must be injected at nearly zero energy though the outer wall , other wise they will collide with the wall after the first path)
>
> This recirculating current is "99 and 44/100 percent" of the input current. If the fusor pressures are low enough for many passes to occur, AND if the trajectory is such that it avoids collisions with the grids or walls, then the probability of fusion increases in some sort of proportional way...
>
> Perhaps you can see where I am going with this..... that by using lower pressures, and more finesse (focussed beams) in beam production, NOT higher voltages and more beam currents, the fusor efficiency should increase.
>
> If something like 200 M degrees K is sufficient for the D-D reaction to occur, then we need only something like a 20 kV potentials. Colliding 20 kV deuterons will be at nearly 40 kV equivalent energy and a collision with a nearly stationary neutral D or D2 will also have sufficient energy.
>
> So quite possibly,,, we should here be thinking of how to build Grid-LESS, LOW pressure, e gun and ion gun fusors.
>
> Comments??
>
> Dave Cooper

[tligon]

My understanding is that even the pros are more likely to talk about burning DT than actually do it. The usual approach at government fusion labs is to run tests with DD, then calculate what would result from DT.

It makes one wonder if real DT powerplants could ever be viable. If the fuel is too scarry for even research, what does that say about breeding it in lithium blankets, extracting it, and refining it in bulk?

[tligon]

Dave,

Having electrons and ions at different kinetic energies is the whole point in the Polywell.

Let's say the target is to have boron converging in the center at 500 keV. A boron nucleus has a charge of +5 if fully stripped of electrons, so you can achieve this energy with an electron potential well depth of 100 kV.

That puts the protons (charge +1) at 100 keV. Work out the velocities from the respective masses and the velocity of the protons is slightly higher than the borons, and velocity is the key input to the fusion rate calculation.

What of the electrons? If Bussard's theory is correct, and they're not in thermal equilibrium with the ions, the electrons actually slow down approaching the center of the reactor. If only electrons were present, they would see the center as a "potential hill" of their own making, and be at zero kinetic energy as they space-charge limit at the center. With ions present there will be a virtual anode formed in the center. Bussard targeted the virtual anode to be controlled to around 15% of potential well depth. That would put the electrons at 15 keV in the center.

This is one of the key strategies to controlling bremsstrahlung radiation. If the machine does thermalize the bremsstrahlung problem with p-B11 becomes as hopeless as it is for a tokamak.

In principle the gridded ETW machine and a Polywell both work this way. A fusor would do it in reverse, except that typical fusors are fairly high pressure and prone to thermalize.

[DaveC]

Shon -

I think most of the speculations I aired are more or less still valid. The work by UWisc and others, seems to point to fusion occurring elsewhere in the volume, besides the central zone. The instrumentation issues are challenging, to be sure, but the few results I've seen look valid.

As to whether bigger is better....I rather doubt it. Larger devices will allow less, restrictions on HV entry paths and quite possibly more uniform grid structures, but the basic problem seems to be, the very low probability of fusion occurring between particles that are slung at each other. This is the fusion cross-section monster.

Extrapolating to the ultimate elctrodeless device, (accomplished by means "unkown to us"...) we have a device in which the only charge that can be injected, after the intial charge-up, is that which replaces the fused particles.

To reach watt levels of neutron generation, [ 10^13 or more n/sec] - a really scary scenario for the amateur scientist...coulombs of charge, seem necessary to be contained. I think this was more or less what Bussard's Magnet system had in mind.

For perspective, at one meter from a coulomb of charge, the potenial is (1/4*pi*epsilonzero) or about 9 geV. Granted, this assumes a point charge of 1C, but it's a rather spectacular thing, in itself. Since the known fusion cross section declines above aproximately 1 MeV, this imagined 1 watt charge cluster would have some optimal dimension.

Going to power levels of interest to the industry is another thing...

But you get the idea.

Dave Cooper

[Richard Hull]

The revival of an ancient posting is often a good thing. However, little has changed siince 2002 in the fusion or fusor biz.

With all the caveats and cautions Dave enumerated in his simple example, we see just how daunting the task of useful fusion is and just making something bigger, even if better is not necessarily a good thing.

I constantly worry about the fusion community falling, albeit with knowledge at the forefront, into the sink hole of the over unity crowd. "if I only had a bigger magnet"/("if we only made this thing bigger"), etc. , "then we would have it licked".

I put the cold fusion and hot fusion communities in similar, but separate hoppers. One has spent a lot more than the other and has comprehensible science and repeatability on its side. Both have made a lot of claims about over unity, momentary spurts of power production, etc., with much fanfare. However, both completely and utterly fail to turn one single head at any power company for they both have yet to produce any real power. To me, that speaks volumes about both approaches. There is a third hopper with the also rans, IEC, ICF, polywell and others that just never seemed to have stood a chance. due to the practitioners not even believing in it after a period or failure to prove even marginal gains.

As always, ideas abound while results are not to be found or seen to be forthcoming.

Richard Hull

[Dustin]

I think Dave nailed one of the problems,

The space charge seems to ensure that all ion entering the grid slow to non fusing energies
before entering the focal region regardless of applied voltage. Neutralizing this with slow electrons as in the polywell seems the correct approach and confining them in this region to limit power usage also needs thought.

Ion creation also has to be such that they don't have enough energy to smack into the opposite wall and have a chance for another go around.

Electrostatic focusing also needs addressing so that the ions cannot collide with accelerating elements (grid)

I have seen very little progress in these fundamental areas.

Steve (aka Dustin)

[DaveC]

There might be a way to make use of things we know about the low ion-ion collision rate in present design spherical to point out what to do to boost the Q.
Here's something to chew on.....

If the fusion cross-section for D-D could be summed across the particle energies and number densities at each energy, of particles in the fusor at a particular operating voltage and current, it seems that some sort of estimate could be obtained for the total number of neutrons that SHOULD be produced.

Whether such a numerical concoction would be within light years of anything measured, is something else again. But we would be simply insisting that physics is happening and we should get certain results. Nothing obviously wrong with that assumption.

So, the number which should be produced, compared to what IS produced, provides a scale factor, that would indicate what ion current was actually participating in the fusion being measured. From that one could determine what fraction of the total ion current, is the fusing ions.

Having this fraction in hand, one could then go about redesigning the electrode
system so as to reduce the unproductive fraction of the ion current.

This redesign might not be so hard, since the electrode heating is by all the ions that probably did nothing other that to help generate ions that were the ones that engaged in fusion.

At very least it would give numbers to the probable ion gun currents needed, which I am guessing are rather small, actually.... Certainly nothing like the tens of mA required now.

Note we are rashly ignoring the issues of chamber and fill gas purity, but I think there are several fusors operating now, that have reached a quite clean state - Jon Rosenstiel's for one, Richard's for another...

Maybe this is something worth discussing some more... perhaps a new thread??

Dave Cooper

[dbrown]

Dave, a quick comment on your statement: "From that one could determine what fraction of the total ion current, is the fusing ions."

I believe that knowing the energy range of ions that produce the largest amount of fusion would be of more interest (unless the issue is just that higher ion energy always produces more fusion events - in which case the whole point is mute) - if most of the very high energy electrons/ions are not producing as much fusion as say a range of lower energy electrons/ions, then energy is being wasted and correcting this could lead to a more efficient power input for a given fusion output. A careful measure of neutron count ver ion energy would might yield an insight on that issue.

I will add that one of the biggest breakthroughs in magnetic fusion in the 90's was cleaning up the plasma with getters (boy - was that unbelievably dumb that those so-called experts ignored such a simple and (to me) obvious vacuum issue for twenty or more years!) So yes, something might be gained by reducing/controlling impurities in the chamber.

[Doug Coulter]

This is the most interesting thread I've seen up here since I've been here --

We have been concentrating here on "brute subtlety" rather than brute force the entire time of our efforts. (I say we and our because that's the case -- I'm just the guy whose lab has the gear in it, but many have helped, including some here)

And it's paying off in far higher Q numbers. We are not a challenge to Jon's output, but our Q is by far the highest here, in various modes other than the stable "sweet spot" when we pay close attention to focus issues, space charge de-focusing, ion to neutral ratios, and gas contaminations. And more recently, getting rid of excess electrons that just waste power. Makes space charge harder to control, but you wind up having to deal with that anyway.

I will say that getting your rig to the point where the "stable" sweet spot will run hands-off for minutes at a time is a very good thing -- it takes that level of control and precision to be able to move on.
So it's not a waste of time or effort. But it's part of the journey, not the destination.

Along the way, we have learned how easy it is to accidentally count EMI as neutrons, how easy it it to put a BTI in an especially hot spot in the non-isotropic neutron output and then cross calibrate to a 3He to make claims that are entirely wrong due to the incorrect assumption of isotropy mixed with a bit of wishful thinking and "selection from random data" effects.

Good science is HARD to do, and you have to be your own most brutal critic to get anywhere good.

We are now working with active, not pure DC drives in the attempt to take this to the next level. It's too early to report results, but what little we've done is very promising. It looks like we are going to multiple grids, using an outer one to gather and focus pure ions before we "fire" the main inner grid to get conditions under some real control -- using the outer grid in a way analogous to what is done in a mass spectrometer, with its own AC type drive (with DC bias of course).

It's always been obvious to this observer that the formulation:

1. Build a "simple" fusor
2. A miracle occurs

Has some serious flaws in reasoning. It actually seems like the mode most are running in is about the worst one there is for net fusion per input watt and that most of the D ions (measured time of flights) are actually going a heck of a lot slower in those circumstances than anything you'd calculate from an oversimplified theory based on voltage inputs. The applied field ain't the net field! Heck, when we measure our plasma (Faraday probe) when running in the "normal" mode, it's not even neutral! And even with an ion gun, it isn't positive, there's a large excess of electrons in it.

We have found that almost anything we do to perturb the "stable mode" actually makes Q go up at some point in the perturbation, or during the return to stability after that. E or H pulses have both been tried, and both do this in various forms. But you can't even find this out until you've gotten to the point of having time-resolved measurements of things to look at, because the other half of the perturbation makes it worse....it's not the answer by itself, just a hint towards what would be.

So we have been going for Q first -- we feel that scaling to real power output can't be done with any confidence until we know the conditions for Q, so we have a clue *what* to scale....

Though I must admit, running a couple kW DC into a fusor is fun for a little while....and nice to be able to try. Till you have, there's always that tickle in the back of the mind that something magic might happen if you did. Our experience is, nope -- but now we are *sure* of that and we stopped wasting time on it.

We have taken heroic measures here in shielding so we don't use ourselves up -- we only left one hole in the shielding for measurement reasons. We've not yet gotten to stopping neutrons (short of room for what that would take here), but we kill off the X rays pretty well with a lot of lead -- my geiger counter sits at near background levels during a run, between me and the fusor (it has a sensitive range where our cosmic background is half scale, and it stays close to the when running).

Our approach when our output gets to dangerous levels is simply to keep scaling *down*, for the present. All we need is enough to measure well out of the noise for what we are doing now -- real power can come after we know what to do to get it!

Assuming you already know seems like a vain folly to us. It seems we know some things now that most others do not -- and we don't think *we* know yet! It's an amazingly fun journey -- and we are finally starting to see a glimmer at the end of the tunnel. Hope it's not a train ;~)

[dbrown]

Doug, quick question (but answer may not be, so shorten as needed.)
When you say "getting rid of excess electrons" how do you go about that?
Thanks for the post and overview, by the way.

[DaveC]

Dennis - You might have missed the point I was trying to make. I've copied your response here so I don't forget what you wrote....


>> "I believe that knowing the energy range of ions that produce the largest amount of fusion would be of more interest (unless the issue is just that higher ion energy always produces more fusion events - in which case the whole point is mute) - if most of the very high energy electrons/ions are not producing as much fusion as say a range of lower energy electrons/ions, then energy is being wasted and correcting this could lead to a more efficient power input for a given fusion output. A careful measure of neutron count ver ion energy would might yield an insight on that issue."<<

>>"I will add that one of the biggest breakthroughs in magnetic fusion in the 90's was cleaning up the plasma with getters (boy - was that unbelievably dumb that those so-called experts ignored such a simple and (to me) obvious vacuum issue for twenty or more years!) So yes, something might be gained by reducing/controlling impurities in the chamber." <<

Some good points, Dennis... especially that about cleaning up the residuals....this is not so easy as it might sound when the environment is a plasma.

Here's my take on your comments.

There are, within all the fusors, a range of ion energies. These occur because the ions are formed in different places within the fusor, and because of their history, since if they don't fuse on the first trip"around", they might collide with gas molecules losing or gaining some energy - which incidentally must be happening otherwise there would be NO fusion at all!! ).

There is also their mixed pedigree to deal with... you have D+, D-D+, H-D+, H+-D, D+-D+ (maybe, maybe not ??), D+-O, D-O+, D+-Cx, D-Cx+ and so on.. a veritable zoo of stuff that has formed - Deuterium - something...molecules, ions..
So even if you formed all these OUTSIDE the fusor shell, and let them in at near zero energy and then accelerated with a constant potential, you would still have a whole stew of velocities and hence equivalent energies..

So what fusion cross-section would you use here? Beats me....

But, if you were to carefully prepare your system, and convince yourself that some of these mystery molecules and combos could be eliminated as theoretically possible, but not really there, then you have left the assortment of stuff you're trying to sling around.

Given that the fusion cross section curve is upward peaking and then downward, and that we mostly operate on the left side of this curve, some sort of distribution of energies can be assumed.

When in doubt, you know the rule of Physics ... Assume a spherical cow...!!

So... take a stab at an assortment of molecular weights and arrive at equivalent energies. This points to a "documented" fusion cross section and hence a probability you can take to the bank... that fusion occurs between these particles, at these energies, at this rate. This generates a prediction of Neutrons/sec for a given number of particles being slung around, per second. That's just another phrase for the total ion current - the only current in the fuor.

That's the Theory, but it's also the Physics... and the Physics works!! It's not wil o wisp.

So now what does the physical system actually produce? Is the instrumentation believable? All of this gives data with error bars on the results side of the page.

Comparison of these to sides.. theoretical prediction versus experimental results is the process we call Science! either side by itself, doesn't do much.

Comparing output neutron rates versus voltages, actually doesn't tell much at all. Only that your instrumentation saw more or less at different input conditions.

It is only when you stick your neck and predict that you should get this much, and you go that much.... that you have any idea at all, whether your methods and analysis are valid.

So... that's the direction from which I am coming. It only recently got this "clear" to me , and it still seems quite foggy... but maybe others can shine some light on the scene.

And.... maybe we should rename the continuation.. With a Better Hammer....??

Dave Cooper

[dbrown]

Dave, your comment: "When in doubt, you know the rule of Physics ... Assume a spherical cow...!! " is fantatic! and I have forgotten those types of rules to make life more easy.

More seriously, I see part of your point and I have been thinking along some lines like that for the last month - that is, try and force an equivalent 'fusor plasma" system into a non-Maxwellian state (possible Birkeland current layers for very a very, very, very short time) for a D-D and D-T fuel - it would be tricky and require the fusion (sorry but only word that makes fits my meaning) of a number of methods that would barrow from everything such as e-beam, direct drive, magnetic, fast ignition, heavy ion, and a minor part of cold fusion (sorry to even mention that subject) and (throwing in the kitchen sink) even aspects of theta pinch to reproduce the fusor State for the ions and electrons but at a far, far higher density, with no significant Gaussian spread to the energies outside the desired range, then for the time periods I hope to hold the system in, the overall collisions amoung all the ions, while significant in their effects, would not give the these ions enough time to settle back into equilibrium and hence, enable the system to momentarily balance in a State where the primary ions would be close in value to what is found in the typical fusor's 'sweet spot". If (ok, here is the part of cow shapes need to be optimized) a significantly higher percentage of particles (a few orders of magitude) would undergo fusion under these ideal conditions, then the total cost in energy to ‘pump’ the system would be very small and far closer to that which is produced (but I no no illusions of break-even.)

Have many of the experimental details worked on paper (which means I know how to draw) but I still have a number of other projects to finish (the ES deuteron Accel/neutron source; my daughter's neutron detector, and a standard fusor (would be nice to try and join the club!) and these are first on the list. The ES accel. project is fast approching final assembly and may get a first light by end of this month.if all holds up.).