Fueling limits in a cylindrical viscosity-limited reactor

Rubin, T.; Kolmes, E. J.; Ochs, I. E.; Mlodik, M. E.; Fisch, N. J.

doi:10.1063/5.0101271

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Fueling limits in a cylindrical viscosity-limited reactor

Rubin, T.·Kolmes, E. J.·Ochs, I. E.·Mlodik, M. E.·Fisch, N. J.

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Abstract

Recently, a method to achieve a “natural hot-ion mode” was suggested by utilizing ion viscous heating in a rotating plasma with a fixed boundary. We explore the steady-state solution to the Braginskii equations and find the parameter regime in which a significant temperature difference between ions and electrons can be sustained in a driven steady state. Here, the threshold for this effect occurs at ρ i ≳ 0.1R. An analytic, leading order low flow solution is obtained, and a numerical, moderate Mach number M ≲ 2 is investigated. The limitation is found to be at moderate Mach numbers.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY Asymptotic analysis Equations of fluid dynamics Fusion reactors Heat transfer Plasma confinement Plasma transport properties Rotational dynamics Viscosity

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Rubin, T., Kolmes, E. J., Ochs, I. E., Mlodik, M. E., Fisch, N. J.. 2022-08-22. Fueling limits in a cylindrical viscosity-limited reactor. https://doi.org/10.1063/5.0101271

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