Lattice Boltzmann model approximated with finite difference expressions
This work addresses a fundamental issue in lattice Boltzmann methods for fluid dynamics, offering a more accurate approximation for computational fluid dynamics practitioners.
The paper identifies incompatibilities in the asymptotic properties of the link-wise artificial compressibility method for fluid approximation and proposes a new FD-LBM scheme using finite differences and nonlinear terms. Tests on shear wave, Stokes modes, and Poiseuille flow show improved accuracy over the standard lattice Boltzmann method with multiple relaxation times.
We show that the asymptotic properties of the link-wise artificial compressibility method are not compatible with a correct approximation of fluid properties. We propose to adapt the previous method through a framework suggested by the Taylor expansion method and to replace first order terms in the expansion by appropriate three or five points finite differences and to add non linear terms. The "FD-LBM" scheme obtained by this method is tested in two dimensions for shear wave, Stokes modes and Poiseuille flow. The results are compared with the usual lattice Boltzmann method in the framework of multiple relaxation times.