抄録
In order to suppress the resonance sound from a Helmholtz resonator by installing a baffle plate into its opening, the sound pressure measurements and the flow visualization were performed. In the sound pressure measurements, it was found that the sound pressure with the baffle plate was much lower than that without the baffle plate. The effect of the baffle plate on the reduction of sound pressure depended on the installation position and angle. In the flow visualization, it was found that the baffle palate made the size of the vortex smaller than that without the baffle plate.