抄録
Aerodynamic sound generated from a separated turbulent shear flow was studied experimentally with measurements of emitted sound, velocity, fluctuating static-pressure and flow visualization. Each velocity and fluctuating static-pressure was measured simultaneously with emitted sound to study relations between aerodynamic sound and vortex motions with spectrum, waveforms, coherence and COP (Coherent Output Power). Ajet was issued from a squared nozzle (0.1m×0.1m) along the flat wall and a two-dimensional sharp-edged fence with a height h of 7mm was placed on the wall to generate the separated turbulent shear flow. The aerodynamic sound generated from the shear flow was measured by a microphone fixed near the fence outside the flow. A velocity at jet center Ue was 35m/s and Reynolds number Re (=Ue h/v) was 1.6×10^4. The present study suggests that the measurements of fluctuating static-pressure give us useful information to study relations between sound source caused by vortex motion and aerodynamic sound.
