Assessment of ALEGRA Computation for Magnetostatic Configurations

Grinfeld, Michael; Niederhaus, John Henry; Porwitzky, Andrew

Title: Assessment of ALEGRA Computation for Magnetostatic Configurations

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Abstract

Here, a closed-form solution is described here for the equilibrium configurations of the magnetic field in a simple heterogeneous domain. This problem and its solution are used for rigorous assessment of the accuracy of the ALEGRA code in the quasistatic limit. By the equilibrium configuration we understand the static condition, or the stationary states without macroscopic current. The analysis includes quite a general class of 2D solutions for which a linear isotropic metallic matrix is placed inside a stationary magnetic field approaching a constant value H_i° at infinity. The process of evolution of the magnetic fields inside and outside the inclusion and the parameters for which the quasi-static approach provides for self-consistent results is also explored. Lastly, it is demonstrated that under spatial mesh refinement, ALEGRA converges to the analytic solution for the interior of the inclusion at the expected rate, for both body-fitted and regular rectangular meshes.

Authors:

Grinfeld, Michael ^[1]; Niederhaus, John Henry ^[2]; Porwitzky, Andrew ^[1]

The U.S. Army Research Laboratory, Aberdeen Proving Ground, MD (United States)
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: Tue Mar 01 00:00:00 EST 2016

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA); ARL

OSTI Identifier:: 1430897

Report Number(s):: SAND-2016-2777J
Journal ID: ISSN 1054-4887; 637591

Grant/Contract Number:: AC04-94AL85000

Resource Type:: Accepted Manuscript

Journal Name:: ACES Journal

Additional Journal Information:: Journal Volume: 33; Journal Issue: 1; Journal ID: ISSN 1054-4887

Publisher:: Applied Computational Electromagnetics Society

Country of Publication:: United States

Language:: English

Subject:: 97 MATHEMATICS AND COMPUTING; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Electrostatics; exact solutions; magnetohydrodynamics; magnetostatics; verification and validation

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                    Grinfeld, Michael, Niederhaus, John Henry, and Porwitzky, Andrew. Assessment of ALEGRA Computation for Magnetostatic Configurations.  United States: N. p., 2016. 
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                    Grinfeld, Michael, Niederhaus, John Henry, & Porwitzky, Andrew. Assessment of ALEGRA Computation for Magnetostatic Configurations.  United States.

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                    Grinfeld, Michael, Niederhaus, John Henry, and Porwitzky, Andrew. Tue .  
"Assessment of ALEGRA Computation for Magnetostatic Configurations".  United States.  https://www.osti.gov/servlets/purl/1430897.

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@article{osti_1430897,

  title        = {Assessment of ALEGRA Computation for Magnetostatic Configurations},

  author       = {Grinfeld, Michael and Niederhaus, John Henry and Porwitzky, Andrew},

  abstractNote = {Here, a closed-form solution is described here for the equilibrium configurations of the magnetic field in a simple heterogeneous domain. This problem and its solution are used for rigorous assessment of the accuracy of the ALEGRA code in the quasistatic limit. By the equilibrium configuration we understand the static condition, or the stationary states without macroscopic current. The analysis includes quite a general class of 2D solutions for which a linear isotropic metallic matrix is placed inside a stationary magnetic field approaching a constant value Hi° at infinity. The process of evolution of the magnetic fields inside and outside the inclusion and the parameters for which the quasi-static approach provides for self-consistent results is also explored. Lastly, it is demonstrated that under spatial mesh refinement, ALEGRA converges to the analytic solution for the interior of the inclusion at the expected rate, for both body-fitted and regular rectangular meshes.},

  doi          = {},

  journal      = {ACES Journal},

  number       = 1,

  volume       = 33,

  place        = {United States},

  year         = {Tue Mar 01 00:00:00 EST 2016},

  month        = {Tue Mar 01 00:00:00 EST 2016}

}

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