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arXiv · 1301.5955

Convecting reference frames and invariant numerical models

Alexander Bihlo·Jean-Christophe Nave
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Abstract

In the recent paper by Bernardini et al. [J. Comput. Phys. 232 (2013), 1-6] the discrepancy in the performance of finite difference and spectral models for simulations of flows with a preferential direction of propagation was studied. In a simplified investigation carried out using the viscous Burgers equation the authors attributed the poorer numerical results of finite difference models to a violation of Galilean invariance in the discretization and propose to carry out the computations in a reference frame moving with the bulk velocity of the flow. Here we further discuss this problem and relate it to known results on invariant discretization schemes. Non-invariant and invariant finite difference discretizations of Burgers equation are proposed and compared with the discretization using the remedy proposed by Bernardini et al..

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Alexander Bihlo, Jean-Christophe Nave. 2013-01-25. Convecting reference frames and invariant numerical models. https://doi.org/10.1016/j.jcp.2014.04.042

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