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DOE OSTI · 1459336

Aleph code electrostatic solver verification

Bettencourt, Matthew Tyler
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Abstract

Aleph is an electrostatic particle-in-cell code which uses the finite element method to solve for the electric potential and field based on external potentials and discrete charged particles. The field solver in Aleph was verified for two problems and matched the analytic theory for finite elements. The first problem showed the mesh-refinement convergence for a nonlinear field with no particles within the domain. This matched the theoretical convergence rates of second order for the potential field and first order for the electric field. Then the solution for a single particle in an infinite domain was compared to the analytic solution. This also matched the theory of first order convergence in both the potential and electric fields for both problems over a refinement factor of 16. These solutions give confidence that the field solver and charge weighting schemes are implemented correctly. This page intentionally left blank.

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97 MATHEMATICS AND COMPUTING

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Bettencourt, Matthew Tyler. 2015-01-01. Aleph code electrostatic solver verification. https://doi.org/10.2172/1459336

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