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This Defense Intelligence Agency reference document, dated 10 March 2010, covers inertial electrostatic confinement (IEC) fusion. It was produced in FY 2009 under the DIA's Advanced Aerospace Weapon System Applications (AAWSA) program. The report focuses on work at the University of Illinois Urbana-Champaign and reviews IEC basics, experiments, theory and applications such as neutron sources, explosives detection and space propulsion. It concludes by proposing a breakeven experiment for p-11B fusion that uses a hydrogen plasma simulation.
“BEAMS”43 pages
UNCLASSIFIED/ ,<F9A: 9FFlil.ltk Wfili 8Hk¥ exponents greater than 2. The first suggestion of this was By R. W. Bussard based on theoretical arguments (see Section 1). Later, PIC studies by M. Ohnishi at Kyoto University (now at Kansai University) also showed such strong scaling (not covered here- but see M. Ohnishi in Proceedings of 16th IEEE/NPSS, vol. 2, pp. 1468-1471). The unanswered question is at what current level this occurs. Future simulations should address that issue and also examine low angular momentum spread and higher ion injection energies. In summary, this study by Tzonev et al. is very encouraging for formation of deep wells in IEC devices designed for reactors using beam-beam dominated fusion. However, much more work needs to be done along these lines to fully identify the optimal ion injection strategy for deep wells with minimum power input. As stressed earlier, the potential well parameters must also be combined with a consistent calculation of the energy gain (Q) following the methods of L. Chacon et al. to establish a complete picture of energy gain possible in a power type IEC. MOMOTA ET AL. - STUDY OF VIRTUAL ELECTRODE STRUCTURE In another related study, Momota and Miley (Reference 4.5) used an analytic solution to examine the angular momentum effects. "Double-well" potential structure (virtual cathode formation) was studied in a stationary spherical IEC using the nonlinear Poison's equations and particle densities derived from kinetic theory. A novel method to obtain a spherically symmetric stationary distribution function is introduced and an integral-differential equation is simplified by applying a relevant approximated formula for an integral. Electron and ion beams are collision-free, and their velocities are roughly aligned toward the spherical center, but with a slight divergence. Analyses show that the angular momentum of ions and the smaller one of the electrons create a virtual cathode, i.e., a double-well structure, of the electrostatic potential on a potential hill near the center. The density limit of an IEC well was found and the conditions relevant to form a deep potential well was presented. These results show trends roughly similar to the numerical studies of Tzonev, et al., and may be useful to persons wanting to study the effects analytically. KIM - STABILITY ANALYSIS In addition to achieving adequate potential well trapping for net energy production, the question of stability of the non-Maxwellian plasma in the well must be considered. (Note that "stability" is a separate question from the thermalization of the beam-like distribution in the IEC discussed earlier. However, they are coupled nonlinear problems due to the fact that the distribution function used for both calculations should be consistent). N. Krall did some earlier studies to show that the distribution in the R.W. Bussard type Polywell IEC are stable against key instabilities such as two-stream. These studies however, were internal company reports and not openly published. Some information is given, however, in Reference 1.7. More recently, H.J. Kim, in his thesis done with G. Miley, did an in-depth study of two stream-like instabilities in the ion- injected type IEC (see Reference 4.6). His work is very encouraging in that he identifies a possible "window of stability" which depends on the injected energy distribution and angular velocity spread. This result is summarized in Figure 4.10. The analysis is briefly described as follows. 41 UNCLASSIFIED/ ;«F81it 8FFI&I.«1k W&liii 911k¥
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Report, from the dia collection. The PDF is mirrored here; the original link is under it. 72 pages are in the text index: search them above, or from the library's search.