Quality assessment of classical and variational multiscale LES simulations of the flow around a circular cylinder

Hilde Ouvrard (1) , Maria-Vittoria Salvetti (2) , Bruno Koobus (1) , Alain Dervieux (3)

1 I3M - Institut de Mathématiques et de Modélisation de Montpellier
2 DIA - Dipartimento Ingegneria Aerospaziale "Lucio Lazzarino"
3 TROPICS - Program transformations for scientific computing

The role of subgrid scale (SGS) viscosity is investigated in LES and VMS-LES simulations of the flow around a circular cylinder at Re=20000 on unstructured grids. The separation between the largest and the smallest resolved scales in the VMS formulation is obtained through a variational projection operator and finite-volume cell agglomeration. Two different non-dynamic eddy-viscosity SGS models are used both in classical LES and in VMS-LES. The sensitivity of the results to different parameters, such as the value of the SGS model input coefficient or the agglomeration level and to numerical viscosity in VMS-LES, is also addressed. Finally, a possible indicator of quality of the LES and VMS-LES predictions is examined.

Mots clés: Variational multiscale LES; circular cylinder; unstructured grids

Domaines: Analyse numérique [math.NA]

Hilde Ouvrard, Maria-Vittoria Salvetti, Bruno Koobus, Alain Dervieux. Quality assessment of classical and variational multiscale LES simulations of the flow around a circular cylinder. Quality and Reliability of Large-Eddy Simulations, QLES2009, 2009, Pise, Italy. pp.131-140, ⟨10.1007/978-94-007-0231-8_12⟩. ⟨hal-00820941⟩