Application of a phased array technique to DNS-generated turbulent subsonic jet data: Source identification and comparison with an analytic model

Abstract

Direct Numerical Simulation (DNS) solutions have previously been obtained for a fully developed turbulent subsonic flow exiting a long pipe into a laminar co-flow. Including the pipe/nozzle in the simulations with a fully turbulent flow upstream should ensure that all possible noise generation mechanisms are represented, although the geometry is unrealistic. A phased array technique called AFINDS has been applied to the sound radiation from the nozzle/jet configuration in order to separate out the distributed jet mixing noise source(s) from nozzle-based sources. The unsteady pressure inside the pipe and at 20 diameters in the far-field is first decomposed into its azimuthal modes and AFINDS ..