Abstract
In order to clarify the generation mechanism of aerodynamic sound from a cavity, noise and flow fields around a cavity were measured with a dynamic PIV system. To capture the vorticity field of high speed flow, frame straddling method was utilized with high-speed CCD camera and infrared Laser. Instantaneous aerodynamic noise and vorticity field were measured by developed system. As a result, the strong noise was generated when the eddy passes through the edge of the forward facing step. At that time, the eddy was deformed. On the other hand, noise level was the lowest when the two eddied were observed in the cavity. It indicated that the spatial deformation of eddies play an important role with the aerodynamic noise generation.
