Hybrid versus pure-LES models comparison for subcritical cylinder flows

Abstract

In Computational Fluid Dynamics applications, there is a need for turbulence models which deliver good predictions for flows involving both laminar and turbulent boundary layers, without knowing in advance the regions where turbulence occurs, and then without changing their parameters according to such an a priori knowledge of the flow characteristics. In this work, which extends the study (Itam et al., 6th Symposium on Hybrid RANS-LES Methods, Strasbourg, France, pp. 26–28, 2016, [7]), we are interested in the assessment of hybrid models for the computation of subcritical flows with laminar boundary layers and in the improvement of the wake behavior prediction in a hybrid RANS/LES model (Itam et al, Application of a hybrid variational multiscale model to massively separated flows. 3AF, Toulouse, France, 2015, [6], Itam et al, 6th Symposium on Hybrid RANS-LES Methods, Strasbourg, France, pp. 26–28, 2016, [7], Moussaed et al, J Fluids Struct 47:114123, 2014, [10]). The performances of a DDES model are compared with a dynamic variational multi-scale (DVMS) large eddy simulation model.