A theoretical discussion based on data re. fusor conditioning fusion

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Richard Hull
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A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

This is my very first posting in this "most serious of forums". While this is a long posting, I have put a lot of thought into it based on real experience and data collected over the years. Bacon's essay on studies is brought to mind... "Read not to believe and take for granted, but to weigh and consider". Those here capable of weighing and considering based on science will appreciate this effort, I believe.

I have noted and put up data on this subject several times in these forums. I have been "conditioning" fusor IV for the HEAS event. I supply a table below of the last 4 day run sessions. This kind of data is representative of every time I have started up my fusor after a moribund period of use. I feel that I am the only one to report on this, perhaps, "my phenomenon". Is it peculiar to fusor IV or the manner in which I operate this system?? Would others see this if operating the way I do? I struggle for about 5 days to condition my fusor after one-half to one full year idle time between one million neutron per second runs. Such runs are not for my pleasure, as a rule. They are for special events or to work on activation experiments which are few and far between. I will use actual experimental observations and data collected over many years of real fusor operations that force me to attempt to explain this "conditioning", as I have dubbed it, in this forum.

In general, I make the following observations from the work of myself and others

1. Few successful fusioneers here ever operate their fusors over a period of years. Most are just "hit-and-run" people, not true amateur fusioneers.
2. The few who do run their fusors over years, rarely report on idle time periods or start up issues.
3. My system always has had a very slow leak, but a leak to the point that if the chamber is left under its last run vacuum for more than a week it is effectively at atmosphere. However, there is not much water vapor to burn off as the fusor pulls to a mechanical vacuum of ~10 microns in a minute or two even after long periods of non-use.
4. First runs after long moribund periods result in only a further reduction of ~2-3 microns with rather significant glow cleaning as the chamber gets quite hot.
5. The bottom for me, with my diff pump running, is on the order of 10e-4 torr.
6. Continuous, day to day running of the fusor never changes this bottoming value. (water and crud all gone)
7. if I run the fusor for 3-4 hours in conditioning tests or in mega mark runs,(re-iterating #5 & #6), as I bring the system down, I first cut the D2 gas flow, leaving the mechanical and hot diff pump running, I now open the chamber to diff pump valve back to wide open and the Baratron gauge dives from the fusion D2 pressure down to 10e-4 torr, the normal bottoming pressure. For years I though it was all about a dirty, unused fusor needing to be cleaned out over time. I no longer accept this hypothesis!

Here is the table
Day 1 Best run 39kv @ 10ma 4.5 microns 22,900 n/s iso
day 2 Best run 38kv @16ma 5.7 microns 42,000 n/s iso
Day 3 Best run 39.7kv @ 6.8 microns 94,800 n/s iso
day 4 Best run 40kv @ 11ma 9 microns 378,100 n/s iso
day 5 Best Run 40kv @ 11ma 9.6 microns 490,100 n/s iso
day 6 Best run 39kv @ 11.6ma 11.7 microns 627,200 n/s iso

Experimental observations

It is plainly obvious that mere voltage in not playing any real part in the fusion over 6 days. Current also has little effect over the period, either. Pressure is key! It was physically impossible to get 9 microns to function on day one after the fusor has not been run for 4 months (June 2018). Trying to introduce 9 microns of deuterium gas on day one would force huge currents at useful fusion voltages that would force electron-runaway. This would increase ionization currents at much lower, non-fusing voltages and melt the grid. It may turn out that pressure is not all that significant beyond increasing the deuterium lattice wall loading maintenance and increasing this loading.

Theoretical machinations

I feel that the higher pressures are possible due to buried deuterium in the SS shell or wall surface lattice by fast neutrals. Why??

1. In the early stages of operation, all water is gone and all things being equal, the leak in my system is uniform and doesn't figure in over time at all.
2. In the beginning, (day one), fusion is due solely to random ionization of the gas increasing voltages and currents work to get advantageous fusions over the entire volume of gas. As the current goes up to increase the ion content so the electron current goes up and the grid heats such that more gas can't be put into the system without reducing fusion and increasing current. This, if continued, will melt the grid.
3. The higher pressure capability increases as the buried deuterium is freed up at the shell walls and is ionized at the wall by the current of very energetic electrons racing for the shell.
4. This "close-shell" ionization puts a huge number of deuterons capable of making it to the grid or the outer grid volume "AT FUSION ENERGY".
5. The ideal is to make deuterons at the shell walls so that the deuterons created there will have the full acceleratory energy of the potential difference between the wall and the grid.
6. Increased flowing gas pressures are possible to feed the wall loaded as fusion increases due to wall based ionization. The increased pressure allows both the random inter grid ionizations seen on day one to join the new wall based ionizations at the same currents and voltages to do a much better job of utilizing both the voltage probabilities and the current driven ionization numbers.
7. Wall ionization currents pour more energy into the deuteron and less into the electron. The electron hits the shell in a tiny acceleratory path while the deuteron gets to accelerate over the entire distance to the grid, (ideally).
8. Meanwhile the near valueless day one events continue to blast electrons into the shell to free more deuterons, now packed into the lattice and the bulk of the inter-volume deuterons fail to fuse, (as on day one), become neutrals and bury into the walls.
9. The above cyclic action continues day after day and often, as seen here, on the 6th or 7th day of operation, I am attaining 1.5million neuts per second isotropic at 39kv and 13ma current and 16 microns of pressure.

My take on conditioning

At first, you can't get a lot of voltage before before getting the fuel pressure up. The high currents with little fusion at reduced voltages does two things. 1. Not much fusion, even though a minimal amount does take place. This is strictly due to "Volume Ionization" where deuterons are created all over the volume of the chamber. The vast majority of deuterons never do fusion as a lot of energy goes to the electrons that blast the shell, while the deuterons tend to wind up as fast neutrals, also bombarding the shell. 2. The profusion of neutrals slowly insinuate themselves into the walls of the fusor such that the fierce electron bombardment pops a few deuterons back out and makes what little fusion happens through a full acceleratory trajectory. This wall loading action continues throughout any given fusor operational session.

In subsequent daily operations this loading continues and more of the current, (energy), supplied goes to doing fusion via wall ionized deuteron release. This reduces electron energies but not so much that they still can't hit the wall and ionize the deuterium. This action allows more fuel to be admitted and more wall loading to take place. The volume ionization still takes place, but this continues to load the wall and creates both fast neutrals and a few fast deuterons. These fast deuterons can do fusion with the ultra high speed shell produced deuterons.

In continued later daily operational scenarios, more fuel can be added and the same current at any given voltage will do more fusion as the process snowballs with more weak electrons and hyper fast wall based deuterons continue all the above previous processes, but on steroids.

Remember all metals, 100% of them, have surface lattices and all absorb hydrogen to a greater or lesser degree. Those of a lesser degree tend to lose their grip on the hydrogen insinuated within them with more ease. (less energy is needed to release the hydrogen than that of a hydrogen hungry metal). Stainless steel is an alloy. It is probably not a great hydrogen absorber and is likely not inclined to hold on to its hydrogen under high energy particle, (electron), bombardment.

Summary

It is all about pressure in operation of the fusor. Pressure increases become more and more possible with wall buried deuterium doing the fusion. Near wall ionization, (deuteron creation), does almost all fusion of significance in a simple fusor. All fusion still takes place over the entire volume of the device. The volumetric fusion is simply enhanced by wall produced deuterons. Those electrons are not a complete waste once the large surface area wall is loaded. The true beauty of the spherical fusor is revealed...A giant surface area loaded with deuterium under constant bombardment of ionizing electrons, while at the same time absorbing both fast and slow neutrals reloading the walls.

edit: new data

Over the last few days, I have noticed something I have seen many times before, but just pushed it aside. (bad form indeed).

In the early "unloaded stages" day1 and day two. I set the D2 gas flow at the lower micron levels and can't seem to get this flow to move up. (important)...I do know that in these early days that the rigidly set gas flow tends to drop only a micron of two as I fiercely try to get the voltage up and the resultant current causes the grid to glow orange hot to almost white hot producing terrible fusion for all the voltage and current poured into the gas. On day 6, as the "walls are loaded" or conditioned, as I posit, I set the gas pressure a little higher than the day before on the first run by maybe one micron. This pressure is dead stable, of course.

I slam the power to the fusor and find that now I do fantastic fusion on the first run on day 6, the voltage rises and the current drops dramatically!! What!! I look at the baratron pressure reading an my 10 micron setting is now at 7.3 microns!! I run the voltage back up, the current goes up and more fusion takes place, the counter is going nuts! Again, the voltage starts going up and the current slips below 8 ma and the pressure is now 6.5 microns. Again...What! I am quickly approaching fusor IVs "rope limit". 42kv. I kill the power and the pressure rises to near my original setting.

I, now, over compensate and open the gas valve to a stable 15 microns figuring it will drop again. It does, indeed, drop to 10 microns as I approach the "42kv rope limit". This is all done in barely enough time to do a 2 minute timed count run as the voltage is rising and the current dropping. The fusion is doing fabulously more as I now have 10 microns at the limit instead of 7.3 or 6.5 as in the last run before upping the pressure for this run.

Any "real fusioneer" out there who has operated their fusor for hours after a huge dead period notice this above effect?

If not a foible peculiar to my fusor, could I be loading and unloading the walls at a rate that sucks up a fraction of my initial pressure??

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

The suggestion has been put forward that wall fusion might be possible. While not rejecting it out of hand, I doubt if much, if any, wall fusion takes place... Why?.... We are pretty much dealing with D-D fusion in the theoretical physics in the fusor and not D2-D2 fusion. It has been recorded by U of W fusor research that inter-volume fusion is significant compared to inner grid fusion. They posited that this might be due to both deuteron-deuteron and deuteron-fast deuterium neutral fusion. Notice that in no instance has it been seen to be fast deuterium neutral-fast deuterium neutral fusion.

It is important to recognize that a wall bound deuterium atom is D2, (deuterium molecule), as such, it is at total rest, (zero energy).

Furthermore, the probability that a fast or high energy deuteron, ( D+) will hit the wall approaches zero, if one noddles it out, i.e., all deuterons are created throughout the volume of the chamber. Based on their birth or creation location, with respect to the accelerating grid location. They are forever doomed to circulate in an orbit no closer to the wall than their point of origin. In general, the MFP, (mean free path), at 10+ microns will limit them to only a few orbits before they become neutrals again, re-joining the gas as a deuterium gas atom again. All neutral gas atoms can be re-ionized at some point, of course, but more than likely they will collide with the walls of the chamber as a fast medium or slow neutral. A fast neutral deuterium molecule impacting a deuterium molecule at total rest in the wall provides a virtual zero probability of fusion.

Far more likely is that an ultra high speed electron or a deuterium molecule, be it fast or slow, hitting a wall loaded deuterium atom will ionize and dislodge it as a deuteron at the wall. This will allow the possibility of this wall ejected deuteron to achieve the full potential gradient acceleratory action to the grid space. There is also a great possibility that a wall bound deuterium molecule (D2), if hit with enough energy, might create two deuterons at the wall.

I think U of W got it right in their research. The bulk of all fusion in the fusor is deuteron-fast neutral fusion with a good bit of deuteron-deuteron fusion near or in the grid space. The huge gas volume in the fusor is a turgid, dynamic, moving target environment for any single deuteron of sufficient energy.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

Please recheck my original first posting above for an edit with new data and observations and a final query to any "real fusioneers".
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Frank Sanns »

The other observation is the "ruddiness" of the plasma and star during start up. It cleans up on consecutive days of operation.

Interestingly, this effect is seen even if the chamber is pumped down to 10E-5 torr for a good part of the day. This should pull out a great deal of water and air that is trapped within the voids of the the inside of the chamber. Still, on introduction of D2, the neutron numbers are not there and the diffuse plasma look is still there even though the "ruddiness" is gone.

I have even brought the pressure up to a few torr from 10E-5 by putting a burst of D2 in and letting it sit for an hour with the chamber sealed off. Even this does not load the walls to any appreciable amount as the neutron numbers are still paltry. It seem the tens of KeV of energy of the deuterons are needed to imbed themselves deeply and ubiquitously in the chamber walls as well as into the grid to do much good.

The only thing that still is needed is time because ALWAYS the next day is better than the end of the first day. Sitting, changing somehow is needed to see the pop in neutron production the next day.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

Frank and others who have done fusion in a fusor know its quirks and how to operate over many sessions. They have acquired the art of running a fusor. The fusor does fusion by bull heading its way through to fusion balanced on the razor thin edge existing between simple glow mode and arc breakdown. Getting a fusor to really do a good deal of fusion is in the operator's artifice coupled to a well done vacuum maintained in flowing deuterium, with a fully instrumented and fully controlled power system that is well bungee-corded.

All fusors, be they new or old ones operated for years that have lain dormant, will require a "conditioning period". This period's length depends on the skill of the operator and the quality of his fusor system and its components. Sure, a brand new superlative fusor can do fusion on day one, but it will do better fusion on successive days at the same voltage and current levels from the day before.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Bruce Meagher »

Richard,

A few additional details of what’s involved in your daily set of runs would be useful. How many are done, and how long is each run? Do you believe it’s just a matter of a particular amount of running time with D2, or do you believe shutting down the system and cool everything plays a part in the increase of neutron production?

Bruce
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

Excellent questions!

I can condition my fusor in about 3-5 days to hit the mega+ n/s mark at 42kv with a flowing D2, (differential pumping pressure) of 16 microns and 12-15 ma.

The first day is a bear as you can see from the numbers. I can easily apply 35-40kv at a few ma, but cannot have any hope of pressure above 5 microns.
On the first day, I might have 10 runs of 2-3 minutes each with full bore voltage, current and pressure forcing me to alter the pressure and voltage and current many times. Total time with the fusor at or near 2-3 hours but running mostly at 25-30 kv trying to inch the pressure up. All to no avail.

The second day is only a bit better, but buoying as the start up to pressure of 6 microns is possible and a bit more fusion is done as seen in the notes. I might run 5 or 6 runs of 4 minutes at as full a throttle as the conditions permit. About 2 hours at the machine.

key point as noted.......Every single day, I start from scratch with the chamber natural "leaked" over the night up to 100 torr or more.

The third day I am really noticing faster time spent with the system coming up to fusion levels with more pressure at all voltages and currents. I spend far less time with the system, but still do 5 or more runs of 4-8 minutes with better fusion and pressures up to 8 or 9 microns.

The fourth day is fabulous doing fusion from start of fore pump to full fusion in 15-20 minutes. Pressures at 10 microns or more. Increasing pressure occurs far more easily and fusion numbers show it.

Day 5 or 6 is often the mega mark day with pressures up to 15+microns.

Now to your last question.....

I can't see running time or shutting down being a part of it. I really think it is a matter of wall loading and only so much can load before it is a futile effort to just run and run the system. I wish I knew more about hydrogen absorption in metal lattices, and SS alloys in particular. I feel that SS is a terrible absorber but bombardment strengthens the absorption, while heating of the device foils the effort, thus forcing one to just shutdown and go home until tomorrow. Maybe the cooling cycle is needed! I will have to take a full day and run a multi on-off cooling pattern to see if I can load in a day.

The good research done in cold fusion on deuterium absorption always interested me. Those guys really learned stuff, albeit in a colder electro-chemical environment. Totally different loading process from the fusor environment.

I hoped this answered a few questions.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Dan Knapp
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Dan Knapp »

A recent paper from Joe Khachan's group in Sydney and their collaborators in Dresden is relevant to this discussion: R. Bowden-Reid et al., Evidence for surface fusion in inertial electrostatic confinement fusion devices, Physics of Plasmas 25: 112702 (2018). Unfortunately, you need to have access to a university library to read this paper, or pay $30 for a copy. The gist of it is that they conclude that collisions between ions and neutral gas molecules adsorbed on the grid account for up to 80% of the measured fusion rate. In addition to the gridded fusor, they also replaced the grid with just plates of various materials. The material that gave the highest surface fusion rate was graphite, followed by silver, titanium, copper, molybdenum, and stainless steel in that order. I recently did some experiments with graphite coated electrodes where I simply sprayed them with graphite lubricant spray. In view of the reported results, it might be interesting to see the effect of spraying a fusor grid with graphite.

Other things in this paper would also be of interest to the fusor community. For their deuterium supply, they used commerically available Hydrostik canisters (ca. $30 ea metal hydride hydrogen storage canisters) which they filled with deuterium by hyrolyzing D2O with a "HydroFill Pro" module. This device is rather pricey (ca. $600 from www.fuelcellstore.com). I think I recall seeing less expensive filling devices in the fuel cell community. This approach has been suggested previously in this forum, (viewtopic.php?f=6&t=10517&p=69748&hilit ... age#p69735) but this is the first report I've seen where someone actually used it for their deuterium supply.

Their neutron detection method is also of interest. They used two helium-3 tubes with their outputs connected in parallel and acquired the detector data by making ten second scans with a Picoscope 3406D. The Picoscopes are a series of digital oscilloscope units that connect to a PC, some of which are of very high performance (and price!). The paper is very scant on details of the detector, but I have been in communication with the first author who gave me more information. The two detector tube outputs were connected and fed into a single charge sensitive preamp, which was connected via a NIM amplifier (which I assume included a peak shaper) to the Picoscope. They acquired ten seconds of detector data at 1 megasample/sec, which then took twenty seconds to download enabling sampling at thirty second intervals. The resulting data was digitally processed to identify neutron peaks and exclude noise. The resulting output is a plot of neutron production over time at thirty second intervals. As has been discussed here previously, the use of gas counting tubes can present challenges to distinguish neutrons from noise. The approach used in the paper would be an affordable one for fusor enthusiasts with the needed programming skills.
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Roberto Ferrari »

Dan
Thanks for that article.
Richard often comments on a progressive increasing of neutron production, after hours/days of fusor running.
May be that explained based in the surface fusion suggested in the paper?
Hours of bombarding the grid with deuterium rise the deuterium stored on grid metals then bringing better efficiency to the operation.
Please comment.
Roberto
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Dan Knapp »

In most of the grid photos I've seen, and in my own very limited experience operating a gridded fusor, the grids are glowing from bombardment heating. It would seem that such heating would tend to drive off adsorbed gas. As such, this effect would seem to work against fusion due to grid bombardment. I need to study this paper more carefully to see if their results could also be explained by wall loading.
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Roberto Ferrari »

Seems to me that your observation is right.
Will wait for your analysis.
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Re: A theoretical discussion based on data re. fusor conditioning fusion

Post by Richard Hull »

Dan, I agree with your assessment of the situation regarding red to orange hot inner grid shedding or expulsion of deuterium atoms as fast as they are buried. In all the literature I have read related to hydrogen in metals, heating tends to drive the hydrogen from the metal. While the wall or shell of a running, fusing fusor heat to near the boiling point of water, this is a huge surface area compared to the grid surface area which is glowing a bright orange heat.

Way back, Carl Willis silver soldered a coiled copper water cooling tube to his fusor halves and noted a significant increase in fusion. We had not noted the possibility of wall loaded deuterium at that time.

The cold fusion people got vast and incredible loadings in the most ideal hydrogen absorptive metals via the slow and gentle electro-chemical processes.

The fusor is very violent in and around the grid for sure. However the wall will only see slow speed, medium speed and high speed neutrals for the vast majority of deuterium loading possibilities. It is the electrons that heat the wall or shell and it is those electrons which most likely ionize the deuterium loading popping out a deuteron at the ideal location, (the wall or shell), to undergo the maximum acceleratory possibility in the fusor reactor vessel.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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