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arXiv · 1210.5289

New velocity-space discretization for continuum kinetic calculations and Fokker-Planck collisions

Matt Landreman·Darin R. Ernst
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Abstract

Numerical techniques for discretization of velocity space in continuum kinetic calculations are described. An efficient spectral collocation method is developed for the speed coordinate - the radius in velocity space - employing a novel set of non-classical orthogonal polynomials. For problems in which Fokker-Planck collisions are included, a common situation in plasma physics, a procedure is detailed to accurately and efficiently treat the field term in the collision operator (in the absence of gyrokinetic corrections). When species with disparate masses are included simultaneously, a careful extrapolation of the Rosenbluth potentials is performed. The techniques are demonstrated in neoclassical calculations of the bootstrap current and plasma flows in a tokamak.

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Matt Landreman, Darin R. Ernst. 2013-02-21. New velocity-space discretization for continuum kinetic calculations and Fokker-Planck collisions. https://doi.org/10.1016/j.jcp.2013.02.041

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