A priori filtering and LES modeling of turbulent two-phase flows application to phase separation

S. Vincent (1) , M. Tavares (1) , S. Fleau (2) , S. Mimouni (3) , M. Ould-Rouiss (1) , Jean-Luc Estivalezes (4)

1 MSME - Laboratoire de Modélisation et Simulation Multi Echelle
2 EDF R&D - EDF R&D
3 EDF R&D MFEE - Mécanique des Fluides, Energies et Environnement
4 DMPE, ONERA, Université de Toulouse [Toulouse]

The Large Eddy Simulation (LES) of two-phase flows with resolved scale interfaces is investigated through the a priori filtering of Direct Numerical Simulations (DNS) of one-fluid and multifield models. A phase inversion benchmark [ 1 –4] is considered highlighting many coalescence and interface rupture events in a kind of atomization process. The order of magnitude of specific two-phase subgrid LES terms is first considered with the two modeling approaches. Then, different existing models such as Smagorinsky [5], Wall-Adapting Local Eddy-viscosity (WALE) model [6], Bardina [7], Mixed [8] and Approximate Deconvo-lution Model (ADM) [9] are used to account for two-phase subgrid effects. These models are compared to filtered DNS results. The main conclusion concerning a priori LES filtering is that the inertia term is not predominant in two-phase flows with fragmentation and rupture of interface. This conclusion is different from that of the studies of [3, 10–13]. Concerning LES models, functional modeling do not correlate to filtered DNS results whereas structural approaches do. Bardina and ADM are clearly the good LES framework to consider for two-phase flows with resolved scale interfaces. ADM is clearly better than Bardina in our study.

Mots clés: LES modeling; A priori filtering; Two-phase flows; One-fluid model; Multi-field approach; Phase inversion

Domaines: Mécanique des fluides [physics.class-ph]

S. Vincent, M. Tavares, S. Fleau, S. Mimouni, M. Ould-Rouiss, et al.. A priori filtering and LES modeling of turbulent two-phase flows application to phase separation. Computers and Fluids, 2018, 176, pp. 245-259. ⟨10.1016/j.compfluid.2016.10.021⟩. ⟨hal-01853399⟩