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arXiv · 0901.1946

Lattice Boltzmann method with self-consistent thermo-hydrodynamic equilibria

M. Sbragaglia·R. Benzi·L. Biferale·H. Chen·X. Shan·S. Succi
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Abstract

Lattice kinetic equations incorporating the effects of external/internal force fields via a shift of the local fields in the local equilibria, are placed within the framework of continuum kinetic theory. The mathematical treatment reveals that, in order to be consistent with the correct thermo-hydrodynamical description, temperature must also be shifted, besides momentum. New perspectives for the formulation of thermo-hydrodynamic lattice kinetic models of non-ideal fluids are then envisaged. It is also shown that on the lattice, the definition of the macroscopic temperature requires the inclusion of new terms directly related to discrete effects. The theoretical treatment is tested against a controlled case with a non ideal equation of state.

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M. Sbragaglia, R. Benzi, L. Biferale, H. Chen, X. Shan, S. Succi. 2009-01-14. Lattice Boltzmann method with self-consistent thermo-hydrodynamic equilibria. https://doi.org/10.1017/s002211200900665x

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