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arXiv · 1511.04572

A Stability notion for the viscous Shallow Water Discrete-Velocity Boltzmann Equations

Mapundi K. Banda·Tumelo R. A. Uoane
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Abstract

The stability of Lattice Boltzmann Equations modelling Shallow Water Equations in the special case of reduced gravity is investigated theoretically. A stability notion is defined as applied in incompressible Navier-Stokes equations in Banda, M. K., Yong, W.- A. and Klar, A: A stability notion for lattice Boltzmann equations. SIAM J. Sci. Comput. {\bf 27(6)}, 2098-2111 (2006). It is found that to maintain stability a careful choice of the value of the reduced gravity must be made. The stability notion is employed to investigate different shallow water lattice Boltzmann Equations. Results are tested using the Lattice Boltzmann Method for various values of the governing parameters of the flow. It is observed that even for the discrete model the reduced gravity has a significant effect on the stability.

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Mapundi K. Banda, Tumelo R. A. Uoane. 2015-11-14. A Stability notion for the viscous Shallow Water Discrete-Velocity Boltzmann Equations. https://arxiv.org/abs/1511.04572

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