Diagnosing numerical Cherenkov instabilities in relativistic plasma simulations based on general meshes
SCIE
SCOPUS
- Title
- Diagnosing numerical Cherenkov instabilities in relativistic plasma simulations based on general meshes
- Authors
- Na, D.-Y.; Nicolini, J.L.; Lee, R.; Borges, B.-H.V.; Omelchenko, Y.A.; Teixeira, F.L.
- Date Issued
- 2020-02
- Publisher
- Academic Press
- Abstract
- Numerical Cherenkov radiation (NCR) or instability is a detrimental effect frequently found in electromagnetic particle-in-cell (EM-PIC) simulations involving relativistic plasma beams. NCR is caused by spurious coupling between electromagnetic-field modes and multiple beam resonances. This coupling may result from the slow down of poorly-resolved waves due to numerical (grid) dispersion and from aliasing mechanisms. NCR has been studied in the past for finite-difference-based EM-PIC algorithms on regular (structured) meshes with rectangular elements. In this work, we extend the analysis of NCR to finite-element-based EM-PIC algorithms implemented on unstructured meshes. The influence of different mesh element shapes and mesh layouts on NCR is studied. Analytic predictions are compared against results from finite-element-based EM-PIC simulations of relativistic plasma beams on various mesh types.
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/113870
- DOI
- 10.1016/j.jcp.2019.108880
- ISSN
- 0021-9991
- Article Type
- Article
- Citation
- Journal of Computational Physics, vol. 402, page. 108880, 2020-02
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- There are no files associated with this item.
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