Enhanced Delayed DES of shock wave/boundary layer interaction in a planar transonic nozzle

Delayed detached-eddy simulations of a Shock Wave/Boundary-Layer Interaction (SWBLI) in an overexpanded transonic nozzle have been carried out to evaluate the performance of different subgrid lengthscales Delta on the computed results. In particular an enhanced DDES is carried out by exploting the Shear Layer Adapted (SLA) subgrid lengthscale Delta(SLA)* recently introduced by Shur et al. [2015] to drastically reduce the turbulent viscosity in the quasi-2D flow regions. Our results show that the enhanced DDES is effective in promoting a faster development of instabilities in the detaching shear-layer, providing improved predictions in terms of mean wall pressure distribution, velocity profiles and frequency of the shock motion with respect to DDES computations performed with classical subgrid lenghtscales.