Saturday, November 30, 2013
New Analysis sees Promise in Focus Fusion
Theoretical models are been refined on the Focus Fusion protocol and there is clearly increasing confidence that continued scaling will produce progressively superior results. Rather important is that the design protocol appears to produce improving results with increasing scale and power inputs while inherently stable. This has been inverse to the experience with Tokomak designs.
Of course we may soon discover otherwise but I do think optimism is justified. As mentioned the technology is about one year away from achieving breakeven with proper funding. For the impatient, that has been the missing ingredient although I must say, scarcity also drives innovation and plenty of rethinking. Yet sooner or later you must cut metal and those tungsten electrodes cannot be faked.
This is continuing good news.
New analysis sees promise in Focus Fusion
Italian physicist analyses Focus Fusion, sees promise
This story is part of LPP's November 4th, 2013 newsletter, available in PDF format here. Join the discussion at the Focus Fusion Society here.
In a third independent analysis of the prospects for pB11 (hydrogen-boron) fusion with the plasma focus device, University of Genoa researcher Andrea Di Vita reports in the European Journal of Physics that ignition of the fuel should be possible, if there is substantial reflection of x-ray energy back into the plasmoid. Earlier, separate analyses by LPP researchers and Iranian researchers in the Journal of Fusion Energy had concluded that ignition and net energy production would be possible even with no reflection of x-rays. Also, in agreement with LPP work, Di Vita concluded that the injection of angular momentum into the plasma (for example by an externally-applied axial magnetic field, as in FF-1) should aid in achieving ignition.
Di Vita’s report makes clear the reason for the somewhat differing conclusions, although all three analyses agree that pB11 with a plasma focus (what LPP has termed “Focus Fusion”) is a promising line of approach to fusion energy. As Di Vita emphasizes, his analysis is based on certain “empirical scaling laws” that he has derived from the literature. As Di Vita writes, “Admittedly, the relevance of available scaling laws to our problem is questionable, to say the least. First of all, they are just rule-of thumb descriptions...” These rules-of-thumb scaling laws differ significantly from the theoretically-derived scaling laws used by LPP, laws which have been significantly confirmed by experiment. For example, Di Vita’s scaling laws do not predict the observed I5 scaling of fusion yield, where I is peak current, while the LPP scaling laws do. Similarly, Di Vita’s calculations predict a constant current in the plasmoid or hot spots of about 0.4 MA, while the LPP believes its calculations and theory more accurately predict increasing plasmoid current with increasing peak current.
Following a friendly exchange on different models with LPP’s Lerner, Di Vita offered to predict the results of FF-1’s upcoming experiments with tungsten electrodes. Stay tuned for the exciting outcome!
- See more at: