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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
P.A. Politzer
Fusion Science and Technology | Volume 27 | Number 3 | April 1995 | Pages 150-160
Overview Paper | doi.org/10.13182/FST95-A11947060
Articles are hosted by Taylor and Francis Online.
Design of an economically attractive tokamak fusion reactor depends on producing steady-state plasma operation with simultaneous high energy density (β) and high energy confinement (τE); either of these, by itself, is insufficient. In operation of the DIII-D tokamak, both high confinement enhancement (H ≡ τE/τITER-89P = 4) and high normalized β (βN ≡ β/(I/aB) = 6%-m-T/MA) have been obtained. For the present, these conditions have been produced separately and in transient discharges. The DIII-D advanced tokamak development program is directed toward developing an understanding of the characteristics which lead to high stability and confinement, and to use that understanding to demonstrate stationary, high performance operation through active control of the plasma shape and profiles.
We have identified some of the features of the operating modes in DIII-D that contribute to better performance. These are control of the plasma shape, control of both bulk plasma rotation and shear in the rotation and Er profiles, and particularly control of the toroidal current profiles. In order to guide our future experiments, we are developing optimized scenarios based on our anticipated plasma control capabilities, particularly using fast wave current drive (on-axis) and electron cyclotron current drive (off-axis). The most highly developed model is the second-stable core VH-mode, which has a reversed magnetic shear safety factor profile [q(0) = 3.9, qmin = 2.6, and q95 = 6]. This model plasma uses profiles which we expect to be realizable. At βN ≥ 6, it is stable to n=1 kink modes and ideal ballooning modes, and is expected to reach H ≥ 3 with VH-mode-like confinement.
