High-order LES benchmarking of confined rotor-stator flows
Résumé
In many engineering and industrial applications the investigation of rotating turbulent flow is of great interest. In rotor-stator cavities, the centrifugal and the Coriolis forces have a strong influence on the turbulence by producing a secondary flow in the meridian plane composed of two thin boundary layers along the discs separated by a non-viscous geostrophic core. Some research has been done using RANS and URANS modelling, however, so far very few investigations have been done using LES. This paper reports on a benchmarking of two high-order LES modelling to predict a turbulent rotor-stator flow at rotational Reynolds number Re=400000. The dynamic Smagorinsky model for the subgrid-scale stress (Germano et al. 1991) is here compared to a spectral vanishing viscosity technique (Séverac and Serre 2006). Results show a good agreement in the predictions of the mean velocities and Reynolds stresses with experimental data with the largest discrepancy occurring in the prediction of the tangential normal stresses Rqq. These both LES modelling are among the firsts to catch the main features of the turbulent flow at this moderately high Reynolds number where rotor-layer goes to turbulence at a local radius close to the periphery. As already noticed by Wu and Squires (2000) on the single disk case, this work offers indirect supports to the idea that in such flows when large-scale motions are accurately resolved - the high-order schemes guarantying a weak dissipative truncation error - LES modelling seems to have only weak effects on the predictions.
Origine : Fichiers produits par l'(les) auteur(s)
Loading...