Analysis of structural-acoustic coupling characteristics of rectangular enclosure with different parameters

A free-vibration model of an acoustic-structural coupled system is built using the modal coupling analysis method. The influences of enclosure depth on resonance frequencies and modal decay time of the structural-acoustic coupling system are analyzed. The change of energy transfer, resonance frequencies, and decay time of the coupling system in panel and enclosure modes is analyzed in detail. The analysis results of panel and rectangular enclosure coupling system are presented. When the enclosure depth is changed, there are two factors which affect the transfer factor between enclosure and panel modes, including enclosure depth and the difference between their resonance frequencies. Near the enclosure depth of strong coupling between the enclosure mode and panel mode, the resonance frequencies of the enclosure-controlled mode and the panel-controlled mode have a phenomenon of jump. While on the enclosure depth of strong coupling between the enclosure mode and the panel mode, the energy flow between enclosure field and the vibration of panel is the largest, and their modal decay time tends to be equal to each other.