A WKB based preconditioner for the 1D helmholtz wave equation

  • D. L. Green
  • , E. D’Azevedo
  • , D. B. Batchelor
  • , N. Bertelli
  • , C. Lau
  • , R. L. Barnett
  • , J. F. Caneses Marin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Frequency-domain full-wave solutions to the cold-plasma problem have become ubiquitous in the study of radio frequency power in fusion plasmas. However, recent efforts at extreme levels of geometric fidelity have revealed fundamental limits in the problem size that can be solved by typical sparse direct solver based methods. These limits are of particular importance in the 3D study of RF launchers, where the number of degrees of freedom required can exceed 100 million. In such cases, it would be advantageous to solve the system via iterative means, but due to the large null space of the curl-curl operator, the convergence properties of algorithms like GMRES are poor. Here we present a physics-based preconditioner in the form of a WKB solution and demonstrate the iterative solution to the frequency-domain Helmholtz problem in 1D for several cases ranging from satisfying the WKB approximation to strongly violating it.

Original languageEnglish (US)
Title of host publication23rd Topical Conference on Radiofrequency Power in Plasmas
EditorsPaul T. Bonoli, Robert I. Pinsker, Xiaojie Wang
PublisherAmerican Institute of Physics Inc.
ISBN (Electronic)9780735420137
DOIs
StatePublished - Sep 16 2020
Event23rd Topical Conference on Radiofrequency Power in Plasmas - Hefei, China
Duration: May 14 2019May 17 2019

Publication series

NameAIP Conference Proceedings
Volume2254
ISSN (Print)0094-243X
ISSN (Electronic)1551-7616

Conference

Conference23rd Topical Conference on Radiofrequency Power in Plasmas
Country/TerritoryChina
CityHefei
Period5/14/195/17/19

All Science Journal Classification (ASJC) codes

  • General Physics and Astronomy

Fingerprint

Dive into the research topics of 'A WKB based preconditioner for the 1D helmholtz wave equation'. Together they form a unique fingerprint.

Cite this