  In many engineering and industrial applications, the investigation of
rotating turbulent flow is of great interest. In rotor-stator cavities, the
centrifugal and 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 disks separated by a non-viscous geostrophic core. Most
numerical simulations have been performed using RANS and URANS modelling, and
very few investigations have been performed using LES. This paper reports on
quantitative comparisons of two high-order LES methods to predict a turbulent
rotor-stator flow at the rotational Reynolds number Re=400000. The classical
dynamic Smagorinsky model for the subgrid-scale stress (Germano et al., Phys
Fluids A 3(7):1760-1765, 1991) is compared to a spectral vanishing viscosity
technique (S\'everac & Serre, J Comp Phys 226(2):1234-1255, 2007). Numerical
results include both instantaneous data and postprocessed statistics. The
results show that both LES methods are able to accurately describe the unsteady
flow structures and to satisfactorily predict mean velocities as well as
Reynolds stress tensor components. A slight advantage is given to the spectral
SVV approach in terms of accuracy and CPU cost. The strong improvements
obtained in the present results with respect to RANS results confirm that LES
is the appropriate level of modelling for flows in which fully turbulent and
transition regimes are involved.

Fluid Dynamics