Joseph Chikva wrote:........
Regarding ions and throun rock.
Let's say that ions are oscillating around center (potential well). Is this acceptable model?
That is reasonable, except recognize that oscillation/ orbiting does not necessarily mean circular orbits. The more elliptical the oscillations (within limits) the better convergence- central focus and resultant core density and fusion.
As far as your approach, I have not sen it, but from comments it seams to be two collimated beams of ions at two different speeds, with some space charge neutralization. The fast beam overtakes the slower beam and hopefully make fusions. Several thoughts:
This sounds like essentially beam target fusion, just with a different frame of reference. Or, if you prefer beam- beam fusion, except with a negative handicap that has to be overcome. With opposed beams the velocities are additive, in this scheme the velocity of the slower beam is subtrative. This means that the total input energy per possible collision goes up. I suppose this might be tolerable if other concerns compensated. But. two moving beams at different velocities is still essentially opposing colliding beams, just with a different frame of reference. If you are concerned about two stream instabilities with opposing beams, how is that different from this scheme?
Using some numbers, and ignoring the losses from the two different speeds in the same direction, if the effective collision energy ~ 100 KeV, then with D-T fuel you might have 10 scattering collisions for each fusion collision. Assume that each scattering collision leads to the loss of one (or should that be two ) ions, and that space charge scattering/ defocus is controlled) . Then for each fusion collisionn (~17 MeV yield) you would lose ~ 1 MeV . This ignores other losses like Bremstrulung, etc. Still you might optimistically expect a net positive Q of perhaps 5-10 (?). With D-D, the scattering collision rate over the fusion rate would be at least 10 times higher, and the yield per fusion might be ~ 6 MeV. So for each 6 MeV fusion you would lose ~ 10 MeV or more. No way to come out with a positive Q. So, this might work with this probably extreamly optimistic analysis, but only with D-T fuel. You could push D-D fuel energies to higher levels and perhaps decrease the scattering to fusion ratios, but other losses would add up- such as Bremsstrulung, and the gain per fusion event would decrease.
From a beam- beam fusion perspective, how is this different from a Polywell? At least ideally, the Polywell is an opposing beam fusion machine. The angular scattering collision perturbations are less significant because of the spherical geometry, and the expectation that many of the scattering collisions will l occur near the center where any angle of dispersion results in only modest change in angular momentum (deviation from radial paths). Even once considerable dispersion has occurred, the fusion efficiency would fall some, but not end. This multi- chance, multi-pass approach ensures significantly better fuel burnup, and does so at only modest input energy requirements.
In a twin tandom beam system, ions would only have one or a few chances to fuse before being lost from the system. Even if you curved the beams around a torus, the scattering reactions would quickly disperse and thermalize the ions- and now you essentially have a Tokamak.
Playing with externally applied electrostatic fields are certainly interesting and results in even more complex interactions, but this has been tried in many mirror designs, and I believe in Tokamaks and FRC machines. The only ones of these that MIGHT work is the Polywell and Tri-Alpha FRC approach. There are possibly others, but I know nothing of them.
Another question. If you are interested in fusion power, not only positive energy balance is required, but also reasonable energy density. A Dense plasma focus, FRC and Polywell may be attrative, The Tokamaks are just to darn big. How would a twin beam approach fair. I suspect that the ion densities within the beams could not be very high, so the fusion yield would be low, even if it was a net positive energy balance.
Dan Tibbets
To error is human... and I'm very human.
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