Nature of ideal MHD instabilities as described by multi-region relaxed MHD
نویسندگان
چکیده
Abstract In this work, the stepped pressure equilibrium code (SPEC) (Hudson et al 2012 Phys. Plasmas 19 112502), which computes equilibria of multi-region relaxed magnetohydrodynamic energy principle (MRxMHD), has been upgraded to determine MRxMHD stability in toroidal geometry. A theoretical formalism for SPEC is obtained by relating second variation functional Hessian matrix, enabling prediction (MHD) linear instabilities. Negative eigenvalues matrix imply instability. Further, we demonstrate our method on simplified test scenarios both tokamak and stellarator magnetic topologies, with a systematic comparison study between marginal ideal MHD packages CAS3D MISHKA-1.
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ژورنال
عنوان ژورنال: Plasma Physics and Controlled Fusion
سال: 2022
ISSN: ['1361-6587', '0741-3335']
DOI: https://doi.org/10.1088/1361-6587/ac53ee