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arXiv · 1308.2120

High order volume preserving integrators for three kinds of divergence-free vector fields via commutator

Huiyan Xue
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Abstract

In this paper, we focus on the construction of high order volume preserving in- tegrators for divergence-free vector fields: the monomial basis, the exponential basis and tensor product of the monomial and the exponential basis. We first prove that the commutators of elementary divergence-free vector fields (EDFVF) of those three kinds are still divergence-free vector fields of the same kind. Assuming then there is only diagonal part of divergence-free vector field of the monomial basis, for those three kinds of divergence-free vector fields, we construct high order volume-preserving inte- grators using the multi-commutators for EDFVFs. Moreover, we consider the ordering of the EDFVFs and their commutators to reduce the error of the schemes, showing by numerical tests that the strategy in [9] works very well.

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Huiyan Xue. 2013-08-09. High order volume preserving integrators for three kinds of divergence-free vector fields via commutator. https://arxiv.org/abs/1308.2120

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