Halo current rotation scaling in post-disruption plasmas

Saperstein, A. R. (ORCID:0000000171111961); Levesque, J. P. (ORCID:000000031193475X); Mauel, M. E. (ORCID:0000000324907478); Navratil, G. A. (ORCID:0000000229305196)

doi:10.1088/1741-4326/ac4186

DOE OSTI · 1838575

Halo current rotation scaling in post-disruption plasmas

Saperstein, A. R. (ORCID:0000000171111961)·Levesque, J. P. (ORCID:000000031193475X)·Mauel, M. E. (ORCID:0000000324907478)·Navratil, G. A. (ORCID:0000000229305196)

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Abstract

Abstract Halo current (HC) rotation during disruptions can be potentially dangerous if resonant with the structures surrounding a tokamak plasma. We propose a drift-frequency-based scaling law for the rotation frequency of the asymmetric component of the HC as a function of toroidal field strength and plasma minor radius ( f rot ∝ 1/ B T a 2 ). This scaling law is consistent with results reported for many tokamaks and is motivated by the faster HC rotation observed in the HBT-EP tokamak. Projection of the rotation frequency to ITER and SPARC parameters suggest the asymmetric HC rotation will be on the order of 10 Hz and 60 Hz, respectively.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY HBT-EP Physics disruption halo current rotation scaling law tokamak

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Saperstein, A. R. (ORCID:0000000171111961), Levesque, J. P. (ORCID:000000031193475X), Mauel, M. E. (ORCID:0000000324907478), Navratil, G. A. (ORCID:0000000229305196). 2022-01-06. Halo current rotation scaling in post-disruption plasmas. https://doi.org/10.1088/1741-4326%2Fac4186

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