ASA 124th Meeting New Orleans 1992 October

4aSA5. Optimization of actuator locations for active control of sound radiation from structures under multiple-frequency excitation.

Tao Song

Chris R. Fuller

Ricardo A. Burdisso

Vib. and Acoust. Labs., Dept. of Mech. Eng., Virginia Polytech. Inst. and State Univ., Blacksburg, VA 24061

The problem of active structural acoustic control (ASAC) of radiation from simply supported rectangular plates under multiple-frequency excitation is studied in this paper. An optimization procedure is presented for optimal location of piezoelectric actuator(s) to actively control the multiple-frequency sound radiation. Expressions for the multiple-frequency radiated sound power by the plate are derived and chosen as the objective function in the optimization approach. Control performance for optimally located actuator(s) are compared with that of actuator locations based on some physical understanding of the system response. In general, it is demonstrated that it is possible to optimally locate actuator(s) in order to effectively control the sound radiation at the frequencies considered. In addition, it is shown that the optimization approach provides a method to design a robust controller with respect to the frequency uncertainty for single-tone excitation cases. [Work supported by ONR.]