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arXiv · 2103.10794

The effect of rigid electron rotation on the Grad-Shafranov equilibria of a class of FRC devices

C. P. S. Swanson·S. A. Cohen
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Abstract

Rigid electron rotation of a fully penetrated Rotamak-FRC produces a pressure flux function that is more peaked than the Solov'ev flux function. This paper explores the implications of this peaked pressure flux function, including the isothermal case, which appear when the temperature profile is broader than the density profile, creating both benefits and challenges to a Rotamak-FRC based fusion reactor. In this regime, the density distribution becomes very peaked, enhancing the fusion power. The separatrix has a tendency to become oblate, which can be mitigated by flux conserving current loops. Plasma extends outside the separatrix, notably in the open field line region. This model does not apply to very kinetic FRCs or FRCs in which there are significant ion flows, but it may have some applicability to their outer layers.

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C. P. S. Swanson, S. A. Cohen. 2021-03-19. The effect of rigid electron rotation on the Grad-Shafranov equilibria of a class of FRC devices. https://doi.org/10.1088/1741-4326%2Fac0f96

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