Structure-preserving finite element approximations of a hybrid relativistic cold fluid-particle model

Tileuzhan Mukhamet; Katharina Kormann

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arXiv · 2510.11500

Structure-preserving finite element approximations of a hybrid relativistic cold fluid-particle model

Tileuzhan Mukhamet·Katharina Kormann

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Abstract

We derive mixed finite element discretizations of a cold relativistics fluid model from approximations of the Poisson bracket that preserve mass, energy and the divergence constraints. For time-discretization we derive an implicit energy-conserving average-vector field method or apply an explicit strong-stability preserving Runge-Kutta scheme. We also consider a coupling of the fluid model to relativistic particles. We perform a numerical study of the scheme which shows convergence and conservation properties of the proposed methods and apply the new scheme to a plasma wake field simulation.

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Tileuzhan Mukhamet, Katharina Kormann. 2025-10-13. Structure-preserving finite element approximations of a hybrid relativistic cold fluid-particle model. https://arxiv.org/abs/2510.11500

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