Semi-Lagrangian off-lattice Boltzmann method for weakly compressible flows

摘要

The lattice Boltzmann method is a simulation technique in computational fluid dynamics. In its standardformulation, it is restricted to regular computation grids, second-order spatial accuracy, and a unity Courant-Friedrichs-Lewy (CFL) number. This paper advances the standard lattice Boltzmann method by introducing asemi-Lagrangian streaming step. The proposed method allows significantly larger time steps, unstructured grids,and higher-order accurate representations of the solution to be used. The appealing properties of the approachare demonstrated in simulations of a two-dimensional Taylor-Green vortex, doubly periodic shear layers, and athree-dimensional Taylor-Green vortex.