Large eddy simulation of supersonic jet noise from a circular nozzle

An imperfectly expanded supersonic jet is simulated with large eddy simulation (LES) method. The full 3D filtered Navier-Stokes equations in cylindrical coordinates coupled with the standard Smagorinsky model are solved by a computational aeroacoustic method. The Dispersion-Relation-Preserving scheme is used for spatial discretization and the low dissipation low dispersion Runge-Kutta method in 2N storage form is utilized for time marching. A high order explicit spatial filter is applied to remove the grid oscillations. An adaptive artificial selective damping is used for shock capturing. The supersonic jet with Mach number 1.19 is simulated. The simultaneous and time average flow field is analyzed. The near filed noise spectra are presented and compared with the experimental data of Ponton et al. and with the numerical results of the present authors by unsteady Reynolds averaged Navier-Stokes (URANS) method. It is shown that the numerical results by LES method agree better with the experimental data than the results by URANS method.