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arXiv · 1505.06900

Increasing stability and accuracy of the lattice Boltzmann scheme: recursivity and regularization

Orestis Malaspinas
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Abstract

In the present paper a lattice Boltzmann scheme is presented which exhibits an increased stability and accuracy with respect to standard single- or multi-relaxation-time (MRT) approaches. The scheme is based on a single-relaxation-time model where a special regularization procedure is applied. This regularization is based on the fact that, for a-thermal flows, there exists a recursive way to express the velocity distribution function at any order (in the Hermite series sense) in terms of the density, velocity, and stress tensor. A linear stability analysis is conducted which shows enhanced dispersion/dissipation relations with respect to existing models. The model is then validated on two (one 2D and one 3D) moderately high Reynolds number simulations ($\mathrm{Re}\sim 1000$) at moderate Mach numbers ($\mathrm{Ma}\sim 0.5$). In both cases the results are compared with an MRT model and an enhanced accuracy and stability is shown by the present model.

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Orestis Malaspinas. 2015-05-26. Increasing stability and accuracy of the lattice Boltzmann scheme: recursivity and regularization. https://arxiv.org/abs/1505.06900

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