Verification of a Lattice-Boltzmann Method by Using Analytical Flow Solutions of Standard Flow Problems

Within the last ten years Lattice Boltzmann solvers have become very popular. They are used for flows inside complex geometries and around bodies like cars, for example. Lattice Boltzmann codes are easy to program because no complex linear equation systems must be solved. Furthermore it is easy to implement different kind of flow models, for example models for multiphase flows. The present paper points out the advantages of Lattice Boltmann methods by comparing results of the Lattice Boltzmann method with analytical and standard CFD results. Under standard CFD the application of a commercial CFD-code is meant. Two standard flows are considered. The first flow under consideration is the laminar boundary layer flow. For example, skin friction values calculated by both a standard CFD-code (FLUENT is applied) and a Lattice Boltzmann code are compared. For the laminar boundary layer flow an analytical solution is available. In the present paper all three results (analytical solution, FLUENT solution, Lattice Boltzmann solution) are compared and discussed. It is demonstrated that the results are in good agreement. Additionally, the 2D-flow around a cylinder for different Reynolds numbers is considered. It is also demonstrated that the Lattice Boltzmann results are in good agreement with the results calculated by the application of FLUENT