Grey area mitigation in hybrid RANS/LES by means of volume forcing
Résumé
The modeled-stress depletion is observed when the fluid flows from a RANS to a LES zone in hybrid modeling due to the dramatic decrease of the modeled stresses and the too slow increase of the resolved stresses. With the aim of developing a general remedy, independent of the type of flow, the present work develops an active approach, which consists in injecting energy in the resolved part to compensate for the loss of energy in the modelled part. Very encouraging results are obtained for channel and periodic hill flows.