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arXiv · 1802.02174

A fluid-kinetic framework for self-consistent runaway-electron simulations

Eero Hirvijoki·Chang Liu·Guannan Zhang·Diego del-Castillo-Negrete·Dylan Brennan
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Abstract

The problem of self-consistently coupling kinetic runaway-electron physics to the macroscopic evolution of the plasma is addressed by dividing the electron population into a bulk and a tail. A probabilistic closure is adopted to determine the coupling between the bulk and the tail populations, preserving them both as genuine, non-negative distribution functions. Macroscopic one-fluid equations and the kinetic equation for the runaway-electron population are then derived, now displaying sink and source terms due to transfer of electrons between the bulk and the tail.

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Eero Hirvijoki, Chang Liu, Guannan Zhang, Diego del-Castillo-Negrete, Dylan Brennan. 2018-03-17. A fluid-kinetic framework for self-consistent runaway-electron simulations. https://doi.org/10.1063/1.5030424

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