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Fusion energy: Progress, partnerships, and the path to deployment
Over the past decade, fusion energy has moved decisively from scientific aspiration toward a credible pathway to a new energy technology. Thanks to long-term federal support, we have significantly advanced our fundamental understanding of plasma physics—the behavior of the superheated gases at the heart of fusion devices. This knowledge will enable the creation and control of fusion fuel under conditions required for future power plants. Our progress is exemplified by breakthroughs at the National Ignition Facility and the Joint European Torus.
M. E. Fenstermacher, N. A. Uckan
Fusion Science and Technology | Volume 4 | Number 2 | September 1983 | Pages 502-506
Plasma Engineering | doi.org/10.13182/FST83-A22913
Articles are hosted by Taylor and Francis Online.
A formalism has been developed in terms of a drift kinetic equation with a Fokker-Planck collision operator to calculate alpha particle loss and energy deposition rate coefficients for one position in space and for steady-state operating conditions in an ELMO Bumpy Torus (EBT) reactor. Pitch angle and energy scattering terms were retained in the collision term so that the analysis provides information on alpha particle behavior due to pitch angle scattering into loss regions in velocity space and information on alpha energy deposition during slowing down in the device. A square well magnetic field shape is assumed and the resulting particle loss rates and energy deposition rates are calculated. For typical EBT reactor parameters, results show that while 80-90% of the alpha particles are scattered into a pitch angle loss region and lost from the device, more than 70% of the alpha particle energy is deposited in the core plasma and about 1–2% goes to alphas retained in the plasma as ash. Parametric studies are performed, and the sensitivity to plasma potential, the pitch angle, the width of loss regions, and computational procedures are analyzed.