Particle subgrid scale modeling in hybrid RANS/LES of turbulent channel flow at low to moderate Reynolds number

Particle dispersion in a periodic channel is studied using the elliptic relaxation hybrid RANS/LES (ER-HRL) model. This approach employs four-equation linear eddy viscosity (LEV) model while Reynolds Averaged Navier-Stokes (RANS) mode near wall, and switches to LES Smagorinsky dynamic outer flow region. We perform systematic analysis of six sets particles having Stokes numbers St = 0.2, 1, 5, 15, 25, 125 at shear Reτ=150, 590. To account for effect unresolved scales on particle dispersion, novel subgrid-scale (SGS) proposed based wall-normal RMS velocity transport equation. The ER-HRL validated against DNS databases, with globally good agreement. For higher number i.e. Reτ 590, model, much coarser grid, outperforms subgrid stochastic acceleration (LES-SSAM) approach.