Internal noise suppression for DNS of a turbulent jet-pipe configuration

Abstract

Detailed analysis of direct numerical simulations (DNS) of a turbulent jet-pipe noise problem has shown that the jet mixing noise can be dominated by internal noise generated within the jet pipe. Preliminary work that reported recently on suppressing the internally generated noise using a canonical acoustic liner model is completed here with a proposed liner design. However the liner is ineffective in attenuating the plane wave mode at low Strouhal numbers. In order to suppress this mode the inflow boundary condition is modified such that the m=0 azimuthal component of the velocity perturbations prescribed at the inflow boundary are set to zero at all radii. It is shown that this has no effe..