A comprehensive algorithm using a fixed toroidal magnetic field for plasma equilibrium with flow
DOI:
https://doi.org/10.31349/RevMexFis.71.061501Keywords:
MHD equilibrium, Toroidal Mach Number, Fixed Toroidal Magnetic Field, Finite Element Method.Abstract
This study presents a finite element method (FEM) solver developed to compute the steady equilibrium of an axisymmetric plasma with toroidal flow. The main objective of the algorithm is to determine the free parameters of the toroidal current source using two key constraints: the measured toroidal magnetic field (TMF) at the magnetic axis and the global error defined by Hilbert. To ensure the accuracy of the performed code, the validation was performed using typical parameters of the JT-60SA (Japan Torus-60 Super Advanced) experiments, and its TMF equal to B0 = 2.25 T. The algorithm reveals a reconstruction error of approximately 0.1% for the flux function. The results also indicate that for a Mach number at the major radius between 0.2 and 0.3, the maximum plasma current reaches 5.5 MA. Furthermore, the normalized beta and safety factor are around 3, the average poloidal beta is 0.8, the normalized inductance is 0.75, and the toroidal frequency (ω) at the major radius is 63 krad/s. These results are found in good agreement with experimental data. Additionally, the study provides a quantitative assessment of how the toroidal flow affects plasma parameters and demonstrates the relationship between poloidal beta and rotation velocity
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