FAQ - fusion in a fusor - How is it done?

It may be difficult to separate "theory" from "application," but let''s see if this helps facilitate the discussion.
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Richard Hull
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FAQ - fusion in a fusor - How is it done?

Post by Richard Hull » Fri Mar 30, 2012 2:29 pm

I was recently asked just how electrons are produced to create the deuterons in the fusor. This also begs the question how is fusion accomplished. Much discussion has ensued over the years on this topic. I will summarize without extensive details how the electrons needed to ionize the gas are produced and why the fusor works so well in spite of being not very eligant, scientifically, as an idealized fusion reactor.

All fusion takes place in velocity space when energetic deuterons, (in our case), are either allowed or forced to collide. The fusion nuclear process is one of quantum tunneling which, we are told, is a purely probablisitic process. A fusion reactor just creates an isolated environment that vastly increases the probability of quatum tunneling and , thus, nuclear fusion.

Enter the fusor...................

Deuterium is our nuclear or fusion fuel. It is the only fuel we can get our hands on at a price that we can afford and is legal to possess. In order to start a fusion process, the first act is to turn the deuterium into deuterons. This is done by stripping the deuterium atom of its electron via ionization, thereby, creating nuclei we call deuterons. This takes place in a plasma and, in our case, using a form of electrical discharge in deuterium gas known as "glow mode".

What hapens in a fusor.................

The source of all ionizing electrons in our deuterium fusion fuel gas is due to high field emission. (High voltage placed across the fusor's shell and inner grid.) These electrons ionize the gas. Fortunately, the ionization needed to strike the plasma, as in a glow lamp, is due solely to the fine wires of the grid creating a localized, very high electrical field in the gas near the wires. This local ionization strikes the plasma. Once ignited and glow mode is stabilized at a user adjusted pressure and voltage, ionization takes place all over the chamber and from here, electron bombardment of the shell produces not only x-radiation over a broad spectrum, but also secondary emission or knock off electrons. It is these electrons that are the ones most valuable to fusion as they ionize deuterium near the shell allowing the possibility of full deuteron acceleration towards the grid and the possible arrival of deuterons there at fusion energy.

We once looked at these shell bound electrons as a total electrical loss, but they may represent the bulk of valued deuteron creation in the fusor! We live and we learn.

We now know, due to experiments, that only a little fusion occurs in the central region of the grid.

The shell presents a giant surface area compared to the grid and is under constant bombardment by electrons and even high energy, neutral gas atoms. All of these have more than enough energy to create a vast number of ionizing electrons at the shell's surface. Likewise, fast neutral deuterium atoms can simply embed themselves in the metal shell's surface. (Common process causing hydrogen embrittlement in many metals) The electron bombardment can both ionize and knock surface locked deuterons back out into the fusor chamber.

The fusor is a terrible design, if elegance is what you are looking for, but it works fabulously, does fusion, is inexpensive by any nuclear reactor standard and functions at a fusion level far beyond most learned casual observers wildest expectations.

If you can imagine it, no matter what it is, it is probably going on in the fusor at some point in velocity space within it. Fusion is just one of those things that is going on. By comparison to the fusion energy taking place, vast amounts of electrical energy are truly being wasted, but the power company promises to deliver all the power we are ready to pay for.

The average fusor that is doing about 1 million fusions per second consumes about 300 watts from the HV supply. The resultant fusion energy is on the order of 6.4 ergs/sec or 1.5x10e-8 watts. We consume about 50 trillion times more energy from the wall outlet than we get out in fusion. Hardly a green project.

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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