Large-eddy simulations of viscoelastic isotropic turbulence with the FENE-P fluid

A new subgrid-scale (SGS) model developed for large-eddy simulations (LES) of dilute polymer solutions described by the Finitely Extensible Nonlinear Elastic constitutive equation closed with the Peterlin approximation (FENE-P), is presented. The filtered conformation tensor evolution equation uses the {\it self-similarity} of the polymer stretching terms, and the {\it global equilibrium} of the trace of the conformation tensor, while the SGS stresses are modelled with the classical Smagorinsky model. The new closure is assessed in direct numerical simulations (DNS) of forced isotropic turbulence using classical {\it a-priori} tests, and in {\it a-posteriori} (LES) showing excellent agreement with all the exact (filtered DNS) results.