Fusor Forums

Hello,

This paper had a big weakness, i.e. I supposed that the magnetic corkscrew device will permit to keep the radial characteristics of the beam, based on the patent . It's a common problem for colliding beam fusion reactors, i.e to prevent the beam to thermalize (even at a certain energy cost). However my first tests (simulations) show that the corkswrew is not the panacea. I'm working on this problematic. Once the solution found (if so), I will update this paper so as to show a possible solution of reactor. If not, this paper has no interest.

Patrick Lindecker

Hello,

To finish with this subject, here are my final observations (deducted from simulations):

* to transform radial speed in axial speed of a beam with particles having different characteristics(speed and position), the magnetic corkscrew is not the solution as it can strongly
reduce or increase the radial speed according to each particle (see http://f6cte.free.fr/Usefulness_of_the_ ... kscrew.pdf).
I have no idea of a possible solution applicable to a neutral beam,

* it is not possible to focalize a beam submitted to a strong magnetic field (5 T) with electrotatic lenses (see http://f6cte.free.fr/Electrostatic_lens ... _Rev_C.pdf). I tested but it was almost obvious as the electrostatic pressure is very weak in front of the magnetic pressure.

So it is not possible (at least for me) to keep the axial characteristics of a narrow beam (in terms of axial to radial speed ratio and in terms of beam diameter).
The morale is that you can't avoid thermalization and particles diffusion (supposed ambipolar for a dense plasma as in tokamaks).

I tested thermalization: in 0.3 second, the beam is almost thermalized, with a mean speed almost equal to 0 (for electrons and ions). To have a perfect thermalization (same quadratic speed in the three directions), it is, however, much longer, as it is a just a tendency.

Patrick Lindecker

Nice follow on; good work!

Yes, Thermalization tends to win, always. One can't bank on living off the Maxwellian tail where the useful energy is concentrated for any form of future energy source.
One is lucky to be able to capture and make use of the peak of the Maxwellian distribution to any degree of percentage recovery.

Richard Hull