FAQ- New ideas, new life and new theory at fusor.net Great!

If you wonder how/why fusion works, or how/why the Fusor works, look here first.
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Richard Hull
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FAQ- New ideas, new life and new theory at fusor.net Great!

Post by Richard Hull » Wed Dec 16, 2020 9:40 pm

This FAQ is dated to include recent activity on this date of publishing.

Based on current activity, a breath of fresh exuberance is being injected into the ongoing efforts at our site. It relates to the last year or so of growing physical experimentation via new construction, neutron activation techniques and ideas from a huge number of valuable postings.

A return to symmetry and active cooling is the thing, it seems.

Increasing the size and mass of the grid assists in suppressing electron emissive runaway. (an age old operational misery) We now know that grid transparency is a dream goal of yesteryear. It has been known for some time that the grid region is NOT where the bulk of all fusion takes place in the simple fusor. It occurs in velocity space within the gas volume. I remember when all of us, still here from the beginnings of this effort, were all noobs and argued that it was all about grid transparency to increase fusion and efficiency. We will never achieve anything like efficiency, energy wise. Efficiency is nothing more than a bragging rite! What we can shoot for is increased fusion and, thus, neutron output for researches using them, even if it means increased losses in the grid's absorption of energy. This means bigger grids with more absorptive energy capabilities and reliance on cooled, loaded symmetrical chamber walls or shells.

This seemed a needed discussion within the theory FAQs based on this current high level of high quality work. The more we do, the more we learn within our narrow little sphere of amateur work with electrostatic fusion.

This whole "cross thingy" began when some poor youngsters did 20-30k n/s in a 2.75 cross, and then another money strapped youngster followed suit with higher numbers, etc.. We might need to get back to symmetry! Crosses work, for sure, but might not be the best road as they are not perfectly symmetrical and contain sharpish nearby edges to the grid and can be tough to manage. (Internal arcing and higher gas conduction currents to the electrostatically sharp edges so near the grid.)

What I see now is reduced to the following theoretical concerns. This is based on my personal operational observations, but more strongly on the work still in progress in recent months by others. What I see as the ideal way to plan a fusor for fusion output, without any regard for power input to output fusion efficiency is now presented.

My thoughts on what should make the best fusor

We might best aim for the smallest possible symmetrical reactor vessel, (mean free path), but not so small that internal arcing is possible at voltages near 50kv applied. We might also figure on larger grids that are symmetrical about the reactor chamber. The grid is constructed to take the extra power needed to do more fusion without becoming a significant source of thermal emitted electrons. (electron runaway conduction in the gas). The fusor must include well thought out active cooling for the entire chamber to allow for longer operation and good wall loading and retention during operation. Also we might design to serve as the ideal closeness to the reactor of a combination moderator-neutron detector-activator and activation recording setup for data collection. The cylinder might solve a lot of these issues as opposed to the sphere, though both answer to the symmetry issue as regard to both vessel and grid construction.

You must remember, this soothsayer, called the cross a possible new paradigm a couple years back....Until I built one thinking it was "all that and a bag of chips"


This is a rare time for this site! Frank Sanns has lamented for some years now that the vibrant nature of the early efforts have become somewhat moribund. Starting with the rage for crosses, more intense and active work both in the doing and in the cogitating and close observations related to results like those by Jon Rosenstiel, Joe Gayo and especially Mark Rowley, we are back in the biz of being vibrant again. With the recent changes in the much more restrictive rules for the plasma club and the neutron club, we have not seen the endless stream of "in it to win it" high schoolers of late. We are left with active "doer researchers" and active theoretical deliberations of some merit, based on real results. This is the reason for this FAQ. It is an update on the activity and theoretical machinations related to amateur fusion in the simple fusor. It is important to work ideas based on observations into a theory of what "might" make a better fusor.

I would welcome any and all comments on this FAQ as this is a starting point for good discussion regarding both theoretical and construction advances. This FAQ attempts to answer the age old, frequently asked question, "How do I make a fusor?"

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: FAQ- New ideas, new life and new theory at fusor.net Great!

Post by Dennis P Brown » Thu Dec 17, 2020 9:09 pm

Certainly true relative to fusor work; however, one should add that over the last few years there have been a few important advances on the hardware side: the development and now rather common practice of using deuterium water to create deuterium gas for a fusor has really matured. The practical development of the chinese electro-static percipitator as a somewhat touchy but relatively inexpensive fusor power supply. These are significant developments on there own, as well. These developments have also been powered by newbie's here and some are no longer newbie's.

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