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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.
Dan M. Goebel
Fusion Science and Technology | Volume 10 | Number 3 | November 1986 | Pages 761-769
Impurity Control | Proceedings of the Seveth Topical Meeting on the Technology of Fusion Energy (Reno, Nevada, June 15–19, 1986) | doi.org/10.13182/FST86-A24832
Articles are hosted by Taylor and Francis Online.
Particle removal from tokamak plasmas is essential to achieve density control and some measure of impurity control. This requirement can be satisfied by pump limiters, the present status of which is reviewed here. Modular experiments have recently achieved particle removal rates over 10 torr-1/sec. Studies of impurity removal by pump limiters have demonstrated He and N2 (moderate Z) exhaust. Successful modeling of the pump limiter performance using Monte-Carlo neutral gas codes has expanded the understanding of the physics of pump limiters. The heat flux to the surface of limiters in tokamaks has been studied in detail. The rapid progress in the engineering, theory, and experimental results of pump limiters has led to plans for the application of these devices in new experiments in the next few years.