Affiliations: Faculty of Engineering, Tokai University,
Kitakaname1117, Hiratsuka-shi, Kanagawa, 259-1292, Japan | Graduate School of Engineering, Tokai University,
Kitakaname1117, Hiratsuka-shi, Kanagawa, 259-1292, Japan
Abstract: In order to study coupling between vibration of a structure and a
sound field in contact with the structure, a cavity surrounded by a rigid
cylinder having thin elastic plates at both ends is adopted as an analytical
model. When excitation forces of different frequencies are applied to the
respective plates, the plate vibrations and the sound field inside the cavity
become aperiodic, because of the coupling between the systems. In the present
investigation, distribution of the sound pressure level inside the cavity is
studied in detail in order to clarify the coupling behavior. The results show
that when the respective plates vibrate at the same circumferential order, the
vibration modes of the plates, which effect the coupling of the plate
vibrations and the sound field, cause the aperiodic nature of each system to
develop. In this case, since the dominant mode exists in formation of the sound
field, it significantly influences the aperiodic nature of the coupling
systems. In the case of vibration modes where the plates vibrate at different
circumferential orders, the behaviors of the three systems, whose coupling has
been restrained, approximate a steady state. Consequently, the dominant mode
does not appear in the sound field.
Keywords: Coupled vibration, Circular end plate, Cylindrical sound field, Distribution of sound pressure level, Modal shape
