Analytical study on plate edge noise (noise generation from tandemly situated trailing and leading edges)

The problem of noise generation due to the interaction between flows and plate edges is treated analytically. In uniform flow containing vorticity waves, two semi-infinite flat plates are placed with the trailing edge of one plate and leading edge of the other being tandemly situated a finite distance apart. This flow is considered to be a simplified model for self-excited tones such as edge tone and cavity noise. An approximate solution to the sound pressure is obtained by the Wiener-Hopf technique, and the calculated acoustic field shows the characteristics of the trailing edge noise and the leading edge noise. The sound pressure level varies with peaks and troughs as the wave number increases, especially in the region upstream from both edges, and these peaks show a frequency dependence similar to edge tones. Such a selective response mechanism will be explained by the phase relationship between vortex and sound.