EPJ Web of Conferences 32, 04017 (2012)
https://doi.org/10.1051/epjconf/20123204017

On the numerical scheme employed in gyrotron interaction simulations

¹ National Technical University of Athens (part of HELLAS), School of Electrical and Computer Engineering, Association EURATOM-Hellenic Republic, GR-15773, Zografou, Greece
² Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
³ University of Latvia, Institute of Solid-State Physics, Association EURATOM-University of Latvia, Kengaraga Street 8, LV-1063, Riga, Latvia
⁴ Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association EURATOM–Confédération Suisse, CH-1015, Lausanne, Switzerland
⁵ Karlsruhe Institute of Technology (KIT), Institute for Pulsed Power and Microwave Technology (IHM), Association EURATOM-KIT, Kaiserstrasse 12, 76131 Karlsruhe, Germany

Abstract

We report on the influence of the numerical scheme employed in gyrotron interaction simulations. Results obtained with the Crank-Nicolson scheme are compared with those obtained with the Backward Time – Centred Space (BTCS) fully implicit scheme. We present realistic cases where, for discretisation parameters in the range usually used in gyrotron simulations, the results can be very different. Hence, the numerical scheme used can be responsible for obscuring the underlying physics if its convergence is not tested carefully.