Plasma rotation plays a crucial role on heat and particle confinement in tokamaks. To consider this issue, we numerically compute the axisymmetric steady states of the visco-resistive magnetohydrodynamic equations, including the non-linear (v·∇)v term using the finite element method. Imposing external n = 0 magnetic perturbations offers a way to break the natural up-down symmetry of the system and produce a net toroidal flow. Using realistic parameters, some numerical results indicate that n = 0 perturbations of the magnetic configuration may be used to increase n = 0 steady-state speeds and promote tokamak plasma confinement while preserving axisymmetry.

Topics
Finite-element analysis, Magnetohydrodynamics, Plasma confinement, Tokamaks, Magnetic confinement fusion, Fluid mechanics, Fluid flows, Viscosity
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