Multimode shunt damping of piezoelectric smart panel for noise reduction.

Multimode shunt damping of piezoelectric smart panel is studied for noise reduction. Piezoelectric smart panel is a plate structure on which a piezoelectric patch is attached with an electrical shunt circuit. When an incidence sound is impinged on the panel structure, the structure vibrates and the attached piezoelectric patch produces an electrical energy, which can be effectively dissipated as heat via the electrical shunt circuit. Since the energy dissipation strongly depends on the vibration mode of the panel structure, many patches are required for multiple vibration modes. Instead of using multiple piezoelectric patches, a single piezoelectric patch is used in conjunction with a blocked shunt circuit for multimode shunt damping. Modeling, shunt parameter tuning, and implementation of the blocked shunt circuit along with an acoustic test of the panel are explained. A remarkable reduction of the transmitted noise was achieved for multiple modes of the panel. Since this technology has many merits in terms of compactness, low cost, robustness, and ease of installation, practical applications in many noise problems can be anticipated.