Large Eddy Simulations of Channel Flow with Fluid Injection through a Porous Wall

In the framework of Solid Rocket Motor (SRM) instability, one of the essential feature is to pinpoint turbulence effect and a critical issue still remains to capture the laminarturbulent transition. The purpose of the present pa per is to carry out three-dimensional numerical simulations of the unsteady flowfield in a channel with fluid injection through a porous wall using LES approach. A first computation with no subgrid scale model is considered, and for a second case a Smagorinsky model is used. The perturbation necessary to launch the transition process is obtained thanks to the time integration scheme used with a CFL value large enough to introduce a numerical destabilization into the flowfield. No slope limiter is used during the computations to su stain this numerical destabilization. For validation purpose, a cold-gas wall channel facilit y is considered and it allows us to compare our numerical approach to experimental data as well as available RANS results. Our findings clearly exhibit an improvement in the lami nar-turbulent transition location and mean and turbulent quantities are fairly in agreeme nt with available experimental data.