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arXiv · 1909.03686

Collisional gyrokinetic full-f particle-in-cell simulations on open field lines with PICLS

Mathias Boesl·Andreas Bergmann·Alberto Bottino·Stephan Brunner·David Coster·Frank Jenko
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Abstract

Applying gyrokinetic simulations for theoretical turbulence and transport studies to the plasma edge and scrape-off layer (SOL) presents significant challenges. To in particular account for steep density and temperature gradients in the SOL, the "full-f" code PICLS was developed. PICLS is a gyrokinetic particle-in-cell (PIC) code and is based on an electrostatic model with a linearized field equation and uses kinetic electrons. In previously published results we were applying PICLS to the well-studied 1D parallel transport problem during an edge-localized mode (ELM) in the SOL without collisions. As an extension to this collision-less case and in preparation for 3D simulations, in this work a collisional model will be introduced. The implemented Lenard-Bernstein collision operator and its Langevin discretization will be shown. Conservation properties of the collision operator as well as a comparison of the collisional and non-collisional case will be discussed.

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Mathias Boesl, Andreas Bergmann, Alberto Bottino, Stephan Brunner, David Coster, Frank Jenko. 2019-09-09. Collisional gyrokinetic full-f particle-in-cell simulations on open field lines with PICLS. https://doi.org/10.1002/ctpp.201900117

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