A secondorder semiimplicit δf method for hybrid simulation
Abstract
A secondorder accurate semiimplicit Lorentz force ions, fluid electrons δf hybrid model has been developed using a “current closure” scheme. The model assumes quasineutrality and is fully electromagnetic. The implicit field solver improves numerical accuracy by separating the equilibrium terms in the presence of small perturbations. The equilibrium part of the generalized Ohm’s law is solved by direct matrix inversion along the direction of gradients for every Fourier mode in the other two directions, while the nonlinear part is solved iteratively. The simulation has been benchmarked on Alfvén waves, ion sound waves and whistler waves against analytical dispersion relation in a slab. In particular, the firstorder and secondorder schemes are compared by studying the numerical damping of whistler waves. The full evolution of the resistive tearing mode using the Harris sheet equilibrium is also investigated. The linear growth rate and mode structure are compared with the resistive MHD theory. Important tearing mode nonlinear phenomena such as the Rutherford regime and saturation are demonstrated. We also presented systematic study of Rutherford growth rates and saturation island width, which is consistent with previous MHD studies.
 Authors:
 Publication Date:
 OSTI Identifier:
 22233609
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics; Journal Volume: 245; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICAL METHODS AND COMPUTING; COMPARATIVE EVALUATIONS; DISPERSION RELATIONS; ELECTRONS; EQUILIBRIUM; HYBRIDIZATION; IONS; ITERATIVE METHODS; LORENTZ FORCE; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; PERTURBATION THEORY; SIMULATION; TEARING INSTABILITY; WHISTLERS
Citation Formats
Cheng, Jianhua, Email: Jianhua.Cheng@Colorado.Edu, Parker, Scott E., Chen, Yang, and Uzdensky, Dmitri A.. A secondorder semiimplicit δf method for hybrid simulation. United States: N. p., 2013.
Web. doi:10.1016/J.JCP.2013.03.017.
Cheng, Jianhua, Email: Jianhua.Cheng@Colorado.Edu, Parker, Scott E., Chen, Yang, & Uzdensky, Dmitri A.. A secondorder semiimplicit δf method for hybrid simulation. United States. doi:10.1016/J.JCP.2013.03.017.
Cheng, Jianhua, Email: Jianhua.Cheng@Colorado.Edu, Parker, Scott E., Chen, Yang, and Uzdensky, Dmitri A.. Mon .
"A secondorder semiimplicit δf method for hybrid simulation". United States.
doi:10.1016/J.JCP.2013.03.017.
@article{osti_22233609,
title = {A secondorder semiimplicit δf method for hybrid simulation},
author = {Cheng, Jianhua, Email: Jianhua.Cheng@Colorado.Edu and Parker, Scott E. and Chen, Yang and Uzdensky, Dmitri A.},
abstractNote = {A secondorder accurate semiimplicit Lorentz force ions, fluid electrons δf hybrid model has been developed using a “current closure” scheme. The model assumes quasineutrality and is fully electromagnetic. The implicit field solver improves numerical accuracy by separating the equilibrium terms in the presence of small perturbations. The equilibrium part of the generalized Ohm’s law is solved by direct matrix inversion along the direction of gradients for every Fourier mode in the other two directions, while the nonlinear part is solved iteratively. The simulation has been benchmarked on Alfvén waves, ion sound waves and whistler waves against analytical dispersion relation in a slab. In particular, the firstorder and secondorder schemes are compared by studying the numerical damping of whistler waves. The full evolution of the resistive tearing mode using the Harris sheet equilibrium is also investigated. The linear growth rate and mode structure are compared with the resistive MHD theory. Important tearing mode nonlinear phenomena such as the Rutherford regime and saturation are demonstrated. We also presented systematic study of Rutherford growth rates and saturation island width, which is consistent with previous MHD studies.},
doi = {10.1016/J.JCP.2013.03.017},
journal = {Journal of Computational Physics},
number = ,
volume = 245,
place = {United States},
year = {Mon Jul 15 00:00:00 EDT 2013},
month = {Mon Jul 15 00:00:00 EDT 2013}
}

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