A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas
Abstract
A highorder finite volume algorithm is developed for the FokkerPlanck Operator (FPO) describing Coulomb collisions in strongly magnetized plasmas. The algorithm is based on a general fourthorder reconstruction scheme for an unstructured grid in the velocity space spanned by parallel velocity and magnetic moment. The method provides density conservation and highorderaccurate evaluation of the FPO independent of the choice of the velocity coordinates. As an example, a linearized FPO in constantofmotion coordinates, i.e. the total energy and the magnetic moment, is developed using the present algorithm combined with a cutcell merging procedure. Numerical tests include the Spitzer thermalization problem and the return to isotropy for distributions initialized with velocity space loss cones. Utilization of the method for a nonlinear FPO is straightforward but requires evaluation of the Rosenbluth potentials.
 Authors:
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 940853
 Report Number(s):
 UCRLJRNL230192
Journal ID: ISSN 00219991; JCTPAH; TRN: US0807225
 DOE Contract Number:
 W7405ENG48
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics, vol. 227, N/A, April 15, 2008, pp. 7192; Journal Volume: 227
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION; 99 GENERAL AND MISCELLANEOUS; ALGORITHMS; EVALUATION; ISOTROPY; LOSS CONE; MAGNETIC MOMENTS; THERMALIZATION; VELOCITY
Citation Formats
Xiong, Z, Cohen, R H, Rognlien, T D, and Xu, X Q. A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas. United States: N. p., 2007.
Web.
Xiong, Z, Cohen, R H, Rognlien, T D, & Xu, X Q. A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas. United States.
Xiong, Z, Cohen, R H, Rognlien, T D, and Xu, X Q. Wed .
"A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas". United States.
doi:. https://www.osti.gov/servlets/purl/940853.
@article{osti_940853,
title = {A HighOrder FiniteVolume Algorithm for FokkerPlanck Collisions in Magnetized Plasmas},
author = {Xiong, Z and Cohen, R H and Rognlien, T D and Xu, X Q},
abstractNote = {A highorder finite volume algorithm is developed for the FokkerPlanck Operator (FPO) describing Coulomb collisions in strongly magnetized plasmas. The algorithm is based on a general fourthorder reconstruction scheme for an unstructured grid in the velocity space spanned by parallel velocity and magnetic moment. The method provides density conservation and highorderaccurate evaluation of the FPO independent of the choice of the velocity coordinates. As an example, a linearized FPO in constantofmotion coordinates, i.e. the total energy and the magnetic moment, is developed using the present algorithm combined with a cutcell merging procedure. Numerical tests include the Spitzer thermalization problem and the return to isotropy for distributions initialized with velocity space loss cones. Utilization of the method for a nonlinear FPO is straightforward but requires evaluation of the Rosenbluth potentials.},
doi = {},
journal = {Journal of Computational Physics, vol. 227, N/A, April 15, 2008, pp. 7192},
number = ,
volume = 227,
place = {United States},
year = {Wed Apr 18 00:00:00 EDT 2007},
month = {Wed Apr 18 00:00:00 EDT 2007}
}

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