Abstract
This paper considers active control of the sound transmission loss of a flexible panel partitioning an open space. Targeting the broadband frequency range, a control strategy presented in the work comprises both active and passive control for the purpose of minimizing the total acoustic power transmitted from a panel excited acoustically from the other side, hence hybrid control. As with a passive control strategy, a double-leaf partition method is employed, thereby enhancing the sound transmission loss in the high frequency range. In the low frequency range, on the other hand, active cluster control is introduced in an effort to suppress the sound transmitted power without causing spillover. Taking advantage of the symmetric properties of the double-leaf structural model, radiation cluster which is an orthogonal contributor with respect to acoustic field can be defined. First, the sound field system produced by a double-leaf wall with air space acoustically excited is described. Cluster control consisting of cluster filtering and cluster actuation is then employed, the system state being expressed. Moreover, the optimal control law for minimizing the total acoustic power radiating from a vibrating panel is derived. A numerical analysis is then conducted, clarifying the control effect for suppressing the transmitted sound power. Finally, an experiment is carried out, demonstrating the capability for enhancing the sound transmission loss using the hybrid control strategy.
