The Lattice-Boltzmann-VLES Method for Automotive Fluid Dynamics Simulation, a Review 2009-26-0057

The lattice Boltzmann (LB) method has been successfully used in conjunction with a Very Large-Eddy Simulation (VLES) turbulence modeling approach for over a decade for the accurate prediction of automotive fluid dynamics. Its success lies in the unique underlying physics that is significantly different from traditional computational fluid dynamics methods. In this paper, we provide a complete description of the method followed by a set of examples which show its use in the automotive industry. We will first provide a review of the physics and numerical methods. Here the LB method and its relationship to kinetic theory and the Navier-Stokes equations will be briefly discussed. We will summarize the strengths of LB method, especially for the solution of transient flows in extremely complex geometries. The VLES turbulence modeling method will be presented next, as well as how VLES neatly fits into the LB framework. We will show that the VLES model provides the unique capabilities of being able to model attached boundary layers (where turbulence models are accurate) while the anisotropic turbulent eddies in separated regions of the flow (where standard turbulence models break down) are resolved by the grid. Following the theoretical description of the LB-VLES method some fundamental examples will be given where detailed experimental results are available for validation. Finally, some summary examples of fully complex production vehicle simulations will be shown, including an example of Total Vehicle Analysis (TVA) which includes aerodynamics, thermal and aeroacoustics prediction.