Acceleration of inertial particles in wall bounded flows: DNS and LES with stochastic modelling of the subgrid acceleration

Rémi Zamansky (1) , Ivana Vinkovic (1) , Mikhael Gorokhovski (1)

1 LMFA - Laboratoire de Mecanique des Fluides et d'Acoustique

Inertial particle acceleration statistics are analyzed using DNS for turbulent channel flow. Along with effects recognized in homogeneous isotropic turbulence, an additional effect is observed due to high and low speed vortical structures aligned with the channel wall. In response to those structures, particles with moderate inertia experience strong longitudinal acceleration variations. DNS is also used in order to assess LES-SSAM (Subgrid Stochastic Acceleration Model), in which an approximation to the instantaneous non-filtered velocity field is given by simulation of both, filtered and residual, accelerations. This approach allow to have access to the intermittency of the flow at subgrid scale. Advantages of LES-SSAM in predicting particle dynamics in the channel flow at a high Reynolds number are shown.

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

Rémi Zamansky, Ivana Vinkovic, Mikhael Gorokhovski. Acceleration of inertial particles in wall bounded flows: DNS and LES with stochastic modelling of the subgrid acceleration. 13th European Turbulence Conference (ETC 13), Sep 2011, Varsovie, Poland. pp.052026, ⟨10.1088/1742-6596/318/5/052026⟩. ⟨hal-00683085⟩