A New Method of Identifying the Aerodynamic Dipole Sound Source in the Near Wall Flow

Consider that the sound dipole source in flow field is composed of multiple micro-spherical oscillating sources. An aerodynamic identification method established by relationship among source, radiated pressure, and pressure gradient near-wall field, formula for calculating power unsteady derived. It shows sources proportional to square force or gradient. The combination CFD further applied around cylinder, which clearly presents location characteristics Further, between separation, vortex shedding, analyzed. corresponding correlation analysis also carried out, indicates exists a finite area attached wall. front end at separation point along circumferential direction wall, where completely falls off trailing begins form. In addition, thickness radial gradually increases backward.