The Motion of Settling Particles in Isotropic Turbulence: Filtering Impact and Kinematic Simulations as Subfilter Model

摘要

Turbulent two-phase flows with small particles are quite common in environmental and industrial contexts. The dispersed phase is involved in a range of phenomena, including preferential concentration, collisions/agglomeration, and wall deposition. In computations of practical flow cases, beyond relatively low Reynolds numbers and simple geometries, DNS reveals to be overly expensive, even in the point-particle approximation with the one-way momentum coupling. Therefore, LES has gained more and more interest over the years. When feasible, the LES becomes particularly well suited for situations where the solution of instantaneous eddy structures is crucial for the prediction of the particulate phase. The subgrid scales (SGS) may have an impact on the motion of particles, especially those of lower inertia. This issue is called here the SGS particle dispersion. Several classes of models have been proposed to account for the effect, as reviewed in [6], but the issue remains open.