Synthetic turbulence generator for lattice Boltzmann method at the interface between RANS and LES

The paper presents a synthetic turbulence generator (STG) for the lattice Boltzmann method (LBM) at interface of Reynolds averaged Navier–Stokes (RANS) equations and LBM large eddy simulation (LES). We first obtain RANS velocity field from finite volume solver interface. Then, we apply numerical interpolation to due different grid types LBM. STG generates fluctuations, regularized reconstructs particle distribution functions perform turbulent channel flow [Formula: see text] with inlet pressure-free boundary condition outlet. is quantitatively compared periodic based LES (LES-LBM) direct (DNS) flow. Both adaptation length time are evaluated. Also, compare STG-LBM results existing (SEM-LBM) results. Our investigations show good agreement DNS LES-LBM within short length. analyzed matches around 1.5–3 domain flow-through time. Finally, check auto-correlation components cross sections streamwise direction. proposed observed be both fast robust. findings potential hybrid RANS/LES-LBM on aerodynamics simulations broad spectrum engineering applications.