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arXiv · 2412.01494

Nonuniqueness of lattice Boltzmann schemes derived from finite difference methods

Eliane Kummer·Stephan Simonis
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Abstract

Recently, the construction of finite difference schemes from lattice Boltzmann schemes has been rigorously analyzed [Bellotti et al. (2022), Numer. Math. 152, pp. 1-40]. It is thus known that any lattice Boltzmann scheme can be expressed in terms of a corresponding multi-step finite difference scheme on the conserved variables. In the present work, we provide counterexamples for the conjecture that any multi-step finite difference scheme has a unique lattice Boltzmann formulation. Based on that, we indicate the existence of equivalence classes for discretized relaxation systems.

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Eliane Kummer, Stephan Simonis. 2024-12-02. Nonuniqueness of lattice Boltzmann schemes derived from finite difference methods. https://arxiv.org/abs/2412.01494

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