PARAMETRIC STUDY OF SEGMENTED TRANSDUCERS LAMINATED ON CYLINDRICAL-SHELLS .2. ACTUATOR PATCHES

The spatial actuation and control effectiveness of distributed segment ed actuator patches laminated on a piezoelectric laminated cylindrical shell are studied. Modal control forces of an arbitrary actuator patc h and also quarterly segmented patches are derived and evaluated. The modal actuation factor, the modal feedback factor and the controlled d amping ratio are derived and their detailed membrane and bending actua tions are evaluated with respect to actuator design parameters: actuat or thickness, shell lamina thickness, shell curvatures, shell sizes an d natural modes. Analytical and simulation results suggest that the me mbrane control action dominates the lower natural modes and it increas es as the shell curvature increases-for deep shells. The bending contr ol action is effective for higher modes and also for shallow or zero-c urvature continua. The modal control effect increases when the actuato r becomes thicker: however, it drops significantly as the shell lamina becomes thicker. (C) 1996 Academic Press Limited