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arXiv · 2403.17322

A novel directly energy-preserving method for charged particle dynamics

Yexin Li·Ping Jiang·Haochen Li
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Abstract

In this paper, we apply the coordinate increment discrete gradient (CIDG) method to solve the Lorentz force system which can be written as a non-canonical Hamiltonian system. Then we can obtain a new energy-preserving CIDG-I method for the system. The CIDG-I method can combine with its adjoint method CIDG-II which is also a energy-preserving method to form a new method, namely CIDG-C method. The CIDG-C method is symmetrical and can conserve the Hamiltonian energy directly and exactly. With comparison to the well-used Boris method, numerical experiments indicate that the CIDG-C method holds advantage over the Boris method in terms of energy-conserving.

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Yexin Li, Ping Jiang, Haochen Li. 2024-03-26. A novel directly energy-preserving method for charged particle dynamics. https://doi.org/10.1016/j.cam.2024.115869

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