Scaling the plasma focus for fusion energy considerations

Abstract

SUMMARYUsing the Lee model code for dense plasma focus, series of numerical experiments were systematically carried out to determine the scaling of bank energies with total current and focus pinch current and the scaling of neutron yields with energies and currents. The numerical experiments were carried out over a range of bank energies from 8 kJ extending up to 24 MJ on the PF1000 and a proposed less damped modern bank. It also includes a study on the effects of increasing bank energies by increasing bank charging voltage and capacitance of the bank for a practical optimum plasma focus machine. The results provide convincing data to show that it is possible to scale up the plasma focus machine at just 3 MJ for D-D neutron yield of 10 13 per shot and 10 15 neutrons per shot when it is converted to operate in D-T.

Numerical Experiments Providing New Insights into Plasma Focus Fusion Devices

“…The versatility and utility of the model are demonstrated in its clear distinction of I pinch from I peak [28] and the recent uncovering of a plasma focus pinch current limitation effect [23,24,29] as static inductance is reduced towards zero. Extensive numerical experiments had been carried out systematically resulting in the uncovering of neutron [21][22][30][31][32][33] and SXR [30][31][32][33][34][35][36][37] scaling laws over a wider range of energies and currents than attempted before. The numerical experiments also gave insight into the nature and cause of 'neutron saturation [31,33,38].…”

Numerical experimentation on focusing time and neutron yield in GN1 plasma focus machine

“…Thus, this explains the importance attached to matching the computed total current trace to the measured total current trace in the procedure adopted by the Lee model code. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Once matched, the fitted model parameters assure that the computation proceeds with all physical mechanisms accounted for, at least in the gross energy and mass balance sense. One of the most important procedures therefore is to tie the numerical experiment to the reality of the actual machine by fitting the computed current trace to a measured current trace.…”

Comparison of Measured Soft X-Ray Yield Versus Pressure for NX1 and NX2 Plasma Focus Devices Against Computed Values Using Lee Model Code

“…The inclusion of the neutron yield, Y n , using beam target mechanism [44,[54][55][56] is one the great step in the development, incorporated in the versions [54,55] of the code (later than RADPF5.13), resulting in realistic Y n scaling with I pinch [44,47,48]. The code has been used to develop scaling laws for soft X-rays [36,[57][58][59][60] and bench-mark numbers and scaling trends for ion beam flux, ion beam fluence, beam ion number, ion beam current, power flow density, and damage factor for all gases [61,62]. Application of ion beam calculations to production of short-lived radioisotopes were made by Akel et al [63].…”