Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: The Original Farnsworth Mark series Fusor.
Date: Jul 11, 11:20 pm
Poster: Hector

On Jul 11, 11:20 pm, Hector wrote:

I was looking at this statement below and I'm not sure I agree with it.

>"However, at a bit lower vacuum level, the ion guns would indeed provide a clean fully accelerated beam of ions at a known current arriving at the inner grid.The problem is they are coming in from only a couple of directions with still fewer collisions per unit current due to reduced gas density."
My reasons are simple.
The role of the virtual cathode is not being taken into account as a means to maintain the density of the plasma core.

"Because of space-charge buildup of the ions and electrons in the core region, virtual anodes and cathodes form in a spherical potential well structure (Miley et al., 1998). This structure greatly enhances the ion confinement and increases the fusing ion density in the center spot."

Also since there is poor evidence of the Farnsworth devices success or failure do to lack of credible data, the issue of the Ion guns is still an open one.

Still, gas density may be low, but the star mode basically mimics ion guns in a way.
I mean the IEC concept is a beam collision system so ion guns shoot beams of "fully accelerated beam of ions" which are fuel.

I would say that burning the fuel more efficiently do to the virtual anodes and cathodes at the core can make up for lower pressures.

Like Miley stated in the past "Only those deuterium ions that are heading for the exact center of each dimple (in the grid cathode electric field) are accelerated towards the middle of the sphere. This leads to the loss of many of the deuterium ions, but turns out to improve the machine's performance overall. The reason for this is that the grid promotes the formation of beams of ions that avoid hitting the wires, preventing corrosion."