2014 Volume 34 Issue 10 Pages 35-41
In this study, a cylindrical structure with end plates at both ends is used and vibroacoustic coupling between the plate vibrations and the internal sound field is investigated theoretically and experimentally when a external harmonic force is applied to one end plate. In the theoretical study, the distribution of sound pressure level is useful for the estimation of complicated coupling phenomena, for which the sound field has some acoustic modes as candidates. As a result, the dimensions, the cylinder length and the radius and thickness of the plate, which promote vibroacoustic coupling, are clarified theoretically, and these theoretical results are demonstrated by the experimental study with variations in the dimensions. Moreover, the circumstance of coupling phenomena, which are promoted or not, is distinguished by not only the obvious increase of peaks in the sound pressure level but also the distribution of that. In particular, the circumstance depends greatly on whether the acoustic mode coupling with the vibration mode is symmetric about the longitudinal direction of the cylinder.
