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arXiv · 2208.03875

Explicit K-symplectic methods for nonseparable non-canonical Hamiltonian systems

Beibei Zhu·Lun Ji·Aiqing Zhu·Yifa Tang
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Abstract

We propose efficient numerical methods for nonseparable non-canonical Hamiltonian systems which are explicit, K-symplectic in the extended phase space with long time energy conservation properties. They are based on extending the original phase space to several copies of the phase space and imposing a mechanical restraint on the copies of the phase space. Explicit K-symplectic methods are constructed for three non-canonical Hamiltonian systems. Numerical results show that they outperform the higher order Runge-Kutta methods in preserving the phase orbit and the energy of the system over long time.

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Beibei Zhu, Lun Ji, Aiqing Zhu, Yifa Tang. 2022-08-08. Explicit K-symplectic methods for nonseparable non-canonical Hamiltonian systems. https://doi.org/10.1088/1674-1056%2Faca9c8

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