We investigate the relation between vortical structures and sound source in isotropic compressible turbulence by direct numerical simulations with various turbulent Mach numbers. The sound source is obtained numerically from the Lighthill equation. As a first step, we study the sound source from the Reynolds stress, which is the dominant source in flows at low Mach numbers. We investigate, especially, sound source structures around the "coherent fine scale eddies" [1-4] to lead a universal conclusion of sound generation mechanism from the fine scale structures in supersonic flows. We find that the sound source structures around the coherent fine scale eddies show some distorted structures only in high Mach number flows because shocklets appear around the fine scale eddies in those flows. This change in sound source structures around the coherent fine scale eddies does not appear in low and moderate Mach number cases.
|Published - 2014
|ASME 2014 International Mechanical Engineering Congress and Exposition, IMECE 2014 - Montreal, Canada
Duration: 2014 Nov 14 → 2014 Nov 20
|ASME 2014 International Mechanical Engineering Congress and Exposition, IMECE 2014
|14/11/14 → 14/11/20