Large-eddy simulation of the noise from a subsonic jet-edge system

The noise from a subsonic jet-edge system is simulated with Large Eddy Simulation (LES) method. The two dimensional and three dimensional filtered Navier-Stokes equations are solved by a computational Aeroacoustics 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 7-point high order explicit spatial filter is applied to replace the subgrid-scale (SGS) model. The subsonic jet-edge system with Mach numbers 0.18 and 0.23 is simulated. The instantaneous flow field is presented, and the interaction of the flow field with the wedge is analyzed. Edge tones are observed being generated at the forepart of the wedge. The near filed noise spectra are plotted and compared with the experimental data of Krothapalli & Horne.¹ Part of the predicted frequencies of the dominant edge tones agree well with the experimental data. The pressure fluctuations on the wedge surface are analyzed. The results show that the second mode of the edge tones is associated with the pressure fluctuations on the forepart of the wedge. The directivity of the dominant edge tones is presented.