Skip navigation
Please use this identifier to cite or link to this item:
Title: Comment on ‘Numerical modeling of tokamak breakdown phase driven by pure Ohmic heating under ideal conditions’
Contributors: Yoo, Min-Gu
Na, Yong-Su
U. S. Department of Energy
Keywords: electrical gas breakdown
direct-implicit scheme
particle simulation
Issue Date: Jun-2019
Publisher: Princeton Plasma Physics Laboratory, Princeton University
Related Publication: Nuclear Fusion
Abstract: In this comment, we point out possible critical numerical flaws of recent particle simulation studies (Jiang et al 2016 Nucl. Fusion 56 126017, Peng et al 2018 Nucl. Fusion 58 026007) on the electrical gas breakdown in a simple one-dimensional periodic slab geometry. We show that their observations on the effects of the ambipolar electric fields during the breakdown, such as the sudden reversal of the ion flow direction, could not be real physical phenomena but resulting from numerical artifacts violating the momentum conservation law. We show that an incomplete implementation of the direct-implicit scheme can cause the artificial electric fields and plasma transports resulting in fallacies in simulation results. We also discuss that their simple plasma model without considering poloidal magnetic fields seriously mislead the physical mechanism of the electrical gas breakdown because it cannot reflect important dominant plasma dynamics in the poloidal plane (Yoo et al 2018 Nat. Commun. 9 3523).
Appears in Collections:Theory and Computation

Files in This Item:
File Description SizeFormat 
README.txt956 BTextView/Download
ARK_DATA.zip456.64 kBUnknownView/Download

Items in Dataspace are protected by copyright, with all rights reserved, unless otherwise indicated.