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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/ ;raA 8FFIIItliL ~81!! SHL'f beam-like ions. Since electron energy loss processes such as radiation emission are serious, the Lawson temperature criterion must be modified for the IEC. A first rough estimate is the Te/T; < 1/3 for DT. (Here T1 and Te are the ion and electron "temperatures", respectively). Control of this ratio is a complex physics issue, involving the relative ion and electron source rates and energies and the potential well structure. In later sections use of p- 11 B (hydrogen-boron-11) fuel in the IEC is considered. This is very attractive since it provides all charged particle reaction products, making this an unique "aneutronic" system. Such a reactor represents a truly ideal system from an environmental and energy sustainability perspective. However, for such fuels, the Larson criterion becomes much more demanding, increasing m by two orders of magnitude and T to 150 kV. Also, for the IEC, a Te/Ti< 1/9 becomes essential. (Using temperature ration is a very simplified representation. The radiation losses are quite sensitive to deviation in the actual energy distribution of the ions and electrons. For example, electron Bremsstrahlung emission primarily comes from the high energy "tail" of the electron distribution while energy transfer with ions is dominated by the "foot" of the electron distribution. At high powers, interactions in these regions can become quite non-linear, depleting or "burning out" the local populations in these regions. This effect causes energy losses to saturate, hence can be quite beneficial under some circumstance. However, the phenomenon is complex to evaluate numerically, so little has been reported on it for IECs to date). The very aggressive p- 11 B Lawson requirement is employed in the design of the breakeven experiment of Section VI. While this discussion of IEC physics has been greatly simplified, it hopefully provides more insight into the basic concepts and issue before delving into more detail. IEC BACKGROUND Inertial Electrostatic Confinement (IEC) was conceived of by Philo Farnsworth, the inventor of electronic television, as an approach to fusion power using electrostatic fields for confinement (Reference 1.2). When he did this in 1955, the prime approaches being pursued worldwide were magnetic confinement or inertial (laser compression of targets) confinement. In fact, electrostatic confinement had been written off by most scientists due to Earnshaw's theorem (Reference 1.4) which stated that plasma could not be confined by electrostatic fields alone. That was simply an expression of the fact that use of a biased plate to confine one species, say ions, would automatically attract the opposite species, electrons, such that the whole plasma would transport to the plate. Farnsworth seemed to intuitively understand that this theorem assumed steady- state, so that if, as in IEC, the ions were dynamically moving and confined, they would electrostatically confine the electrons. Farnsworth went further and realized that in a spherical system virtual electrodes would form a high density plasma region if the confined ions were focused at the center of the sphere (Reference 1.2). While Hirsh worked with Farnsworth to demonstrate early experimental success with IEC experiments (Reference 1.2), the concept passed from view as magnetic and inertial confinement research exponentiated. Then in the late 1990s R. W. Bussard revived the concept with the hybrid IEC magnetic approach (Reference 1.6-1.7). In this approach the electrons were confined in the magnetic field, forming a potentials trap for ions. [Note the similarity to the original conceptual potential well discussed by Elmore, et al. (Reference 1.1)]. Upon invitation by R.W. Bussard to join this effort, the author, George Miley, undertook supporting experiments that were a variation of the original 3 UNCLASSIFIED/ ,CF8A: 8FFIEIPk IP&'i Ollk¥
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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.