Optimal Design of Piezoelectric Smart Structures for active cabin noise control

Optimal design of piezoelectric smart structures is studied for cabin noise problem and an experimental verification is investigated. A rectangular enclosure of which one side of the enclosure is made with a plate while the rest sides are assumed to be rigid is considered as a cabin. Disk shaped Piezoelectric sensors and actuators are mounted on the plate structure and the sensor signal is returned to the actuator with a negative gain. An optimal design of the piezoelectric structures for active cabin noise control is performed. The design variables are locations and sizes of disk shaped piezoelectric actuators and sensors, and actuator gain. The excitation frequency is chosen for a resonance as well as off resonance of the coupled system. To model the enclosure structure, the finite element method which is based on a combination of three dimensional piezoelectric, flat shell and transition elements, is used. For the interior acoustic medium, the theoretical solution of a rectangular cavity in the absence of elastic structure is used and the coupling effect is included in the finite element equation. The optimal design is performed at several frequencies and the results show a remarkable noise reduction in the cavity. An experimental verification of the optimally designed configuration is performed and it confirms the feasibility of piezoelectric smart structures in cabin noise problems.