Guillaume Tauzin
University of Rome "Tor Vergata", Italy

Entropic Lattice Boltzmann as an implicit Large-Eddy Simulation: Insights from 2D turbulence

We study the modelling of turbulence implied by the unconditionnally stable Entropic Lattice Boltzmann Method (ELBM). We first focus on 2D homogeneous turbulence, for which we conduct numerical simulations for a wide range of relaxation times to study the dissipative properties of ELBM. For these simulations, we analyze the effective viscosity by numerically differentiating the kinetic energy and enstrophy balance equations averaged over a subdomain of the computational grid. We aim at understanding the behavior of the implied sub-grid scale model and verify a proposal previously made using Chapman-Enskog expansion. These ELBM benchmark simulations are thus useful to understand the range of validity of ELBM as a turbulence model. Finally, we will discuss an extension of the previously obtained results to the 3D case.