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Time-Independent Gravitational Fields in the BGK Scheme for Hydrodynamics

Adrianne Slyz·Kevin H. Prendergast
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Abstract

We incorporate a time-independent gravitational field into the BGK scheme for numerical hydrodynamics. In the BGK scheme the gas evolves via an approximation to the collisional Boltzmann equation, namely the Bhatnagar-Gross-Krook (BGK) equation. Time-dependent hydrodynamical fluxes are computed from local solutions of the BGK equation. By accounting for particle collisions, the fundamental mechanism for generating dissipation in gas flow, a scheme based on the BGK equation gives solutions to the Navier-Stokes equations: the fluxes carry both advective and dissipative terms. We perform numerical experiments in both 1D Cartesian geometries and axisymmetric cylindrical coordinates.

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Adrianne Slyz, Kevin H. Prendergast. 1999-05-19. Time-Independent Gravitational Fields in the BGK Scheme for Hydrodynamics. https://doi.org/10.1051/aas%3A1999389

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