A singular finite element technique for calculating continuum damping of Alfvén eigenmodes
Abstract
Damping due to continuum resonances can be calculated using dissipationless ideal magnetohydrodynamics provided that the poles due to these resonances are properly treated. We describe a singular finite element technique for calculating the continuum damping of Alfvén waves. A Frobenius expansion is used to determine appropriate finite element basis functions on an inner region surrounding a pole due to the continuum resonance. The location of the pole due to the continuum resonance and mode frequency is calculated iteratively using a Galerkin method. This method is used to find the complex frequency and mode structure of a toroidicityinduced Alfvén eigenmode in a large aspect ratio circular tokamak and is shown to agree closely with a complex contour technique.
 Authors:
 Research School of Physical Sciences and Engineering, Australian National University, Acton, ACT 0200 (Australia)
 Publication Date:
 OSTI Identifier:
 22408069
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ALFVEN WAVES; ASPECT RATIO; DAMPING; EIGENVALUES; FINITE ELEMENT METHOD; ITERATIVE METHODS; MAGNETOHYDRODYNAMICS; RESONANCE; TOKAMAK DEVICES
Citation Formats
Bowden, G. W., and Hole, M. J.. A singular finite element technique for calculating continuum damping of Alfvén eigenmodes. United States: N. p., 2015.
Web. doi:10.1063/1.4907792.
Bowden, G. W., & Hole, M. J.. A singular finite element technique for calculating continuum damping of Alfvén eigenmodes. United States. doi:10.1063/1.4907792.
Bowden, G. W., and Hole, M. J.. 2015.
"A singular finite element technique for calculating continuum damping of Alfvén eigenmodes". United States.
doi:10.1063/1.4907792.
@article{osti_22408069,
title = {A singular finite element technique for calculating continuum damping of Alfvén eigenmodes},
author = {Bowden, G. W. and Hole, M. J.},
abstractNote = {Damping due to continuum resonances can be calculated using dissipationless ideal magnetohydrodynamics provided that the poles due to these resonances are properly treated. We describe a singular finite element technique for calculating the continuum damping of Alfvén waves. A Frobenius expansion is used to determine appropriate finite element basis functions on an inner region surrounding a pole due to the continuum resonance. The location of the pole due to the continuum resonance and mode frequency is calculated iteratively using a Galerkin method. This method is used to find the complex frequency and mode structure of a toroidicityinduced Alfvén eigenmode in a large aspect ratio circular tokamak and is shown to agree closely with a complex contour technique.},
doi = {10.1063/1.4907792},
journal = {Physics of Plasmas},
number = 2,
volume = 22,
place = {United States},
year = 2015,
month = 2
}

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