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Title: Finite Element in Angle Unit Sphere Meshing for Charged Particle Transport.

Abstract

Finite element in angle formulations of the charged particle transport equation require the discretization of the unit sphere. In Sceptre, a three-dimensional surface mesh of a sphere is transformed into a two-dimensional mesh. Projection of a sphere onto a two-dimensional surface is well studied with map makers spending the last few centuries attempting to create maps that preserve proportion and area. Using these techniques, various meshing schemes for the unit sphere were investigated.

Authors:
 [1];  [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA), Office of Defense Science (NA-113)
OSTI Identifier:
1401940
Report Number(s):
SAND2017-11126R
657820
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; charge particle transport; finite element in angle; sphere projection onto surface

Citation Formats

Ortega, Mario Ivan, and Drumm, Clifton R. Finite Element in Angle Unit Sphere Meshing for Charged Particle Transport.. United States: N. p., 2017. Web. doi:10.2172/1401940.
Ortega, Mario Ivan, & Drumm, Clifton R. Finite Element in Angle Unit Sphere Meshing for Charged Particle Transport.. United States. doi:10.2172/1401940.
Ortega, Mario Ivan, and Drumm, Clifton R. 2017. "Finite Element in Angle Unit Sphere Meshing for Charged Particle Transport.". United States. doi:10.2172/1401940. https://www.osti.gov/servlets/purl/1401940.
@article{osti_1401940,
title = {Finite Element in Angle Unit Sphere Meshing for Charged Particle Transport.},
author = {Ortega, Mario Ivan and Drumm, Clifton R.},
abstractNote = {Finite element in angle formulations of the charged particle transport equation require the discretization of the unit sphere. In Sceptre, a three-dimensional surface mesh of a sphere is transformed into a two-dimensional mesh. Projection of a sphere onto a two-dimensional surface is well studied with map makers spending the last few centuries attempting to create maps that preserve proportion and area. Using these techniques, various meshing schemes for the unit sphere were investigated.},
doi = {10.2172/1401940},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Technical Report:

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  • A technique has been created to combine the mapped mesh and free mesh generation capabilities of the SUPERTAB finite element modeling program within the same model. Element compatibility between regions where the two methods are to be used is attained by forcing the unmapped elements to match the mapped elements at the common boundary. This report presupposes a knowledge of the SUPERTAB software.
  • A method is described for calculating the interaction between an imploding liner, a magnetically confined charge particle ring (Astron e-layer, ion ring) and a target plasma, based on the equations of the equivalent circuit. Expressing the electrodynamical behavior in terms of inductive coupling between circular current loops, so that changes in geometry and plasma parameters are described by changes in the induction coefficients, means that only ordinary differential equations arise, in contrast with fluid descriptions. Induced electron currents are conveniently included in the model. Application to a beam-target fusion system driven by the compression of an ion ring is describedmore » as an illustration of the utility of the technique. (Author)« less