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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.
Osamu Mitarai, Akira Hirose, Harvey M. Skarsgard
Fusion Science and Technology | Volume 20 | Number 2 | September 1991 | Pages 208-221
Technical Paper | Plasma Engineering | doi.org/10.13182/FST91-A29691
Articles are hosted by Taylor and Francis Online.
The ignition access condition is described based on the operation path and the saddle point in the generalized ignition contour map . With a confinement scaling law such as for the energy confinement time in terms of the net input heating power density, as employed in most Plasma Operation Parameter Contour (POPCON) analyses, where τE,L is the L-mode confinement time and Cop is the constant parameter, the ignition access condition is given by , where is the height of the generalized saddle point. The height of the generalized saddle point for various arbitrary plasma parameters enables a reactor designer to look at the overall behavior of a reactor. The confinement enhancement factor γH is determined relative to the L mode, which is required for reaching ignition in a tokamak or stellarator reactor. This operation path method is compared with the POPCON approach, and the relative merits of each are discussed.