Smart materials are increasingly used in structural control of vibration and wave propagation. Most of existing studies have focused on the vibration control using smart materials in the form of patches or films, and ring-type has seldom been used. There is not much research on control of cylindrical shells using tunable materials. To meet this need, the present study develops theoretical models for adaptively-passive and active control of vibration and wave propagation in cylindrical shells using smart materials. One unique characteristic of shape memory alloy (SMA), i.e., the controllable elastic modulus with respect to temperature, is adopted in adaptively-passive control of vibration; with the capability of providing line circumferential distributed control forces due to their property of piezoelectricity in piezoelectric ceramic materials (e.g., PZT), the ring-type actuators are proposed to actively control the forced vibration response. The cylindrical shells both in vacuo and filled with fluid are investigated, and two different problems are considered: one is the wave propagation and transmission, and the other is the forced vibration response from external excitation.; With the controllable elastic modulus of SMA, SMA wall joint has the capability of controlling the vibration source with wide-band frequencies or with a time-varying frequency. With the solution of the characteristics of the free wave propagation from the dispersive equation, the vibration response and characteristics of reflection/transmission from incident wave are investigated by using the wave approach and the method of residues. Numerical simulation indicates that the SMA wall joint has the potential to solve the problem of pass-band, and the transmission loss is more than 20dB for all frequency ranges providing a proper temperature. This SMA wall joint is also adopted to adaptively control the forced vibration response from external excitation. Parametric study demonstrates that the SMA joint has the capability of controlling the forced vibration of the shell excited by external excitation, and increasing damping ratio in the SMA joint does not mean to improve its vibration control performance.; With the property of piezoelectricity, the piezoelectric ceramic material is able to function as both sensors and actuators. With the capability to offer more control authority by providing active control line force/moment, the ring-type PZT actuator (being modeled as a line circumferential distributed control force) is adopted to actively control the vibration in cylindrical shell. The transmission loss of this active control method is obtained by using the theory of residues. Simulation results demonstrate that it is possible to achieve a vibration reduction of 20 dB for the shells both in vacuo and filled with fluid by using only one control force.; In summary, the present study illustrates the effectiveness and capabilities of smart materials (e.g., SMA and PZT) on control of vibration and wave propagation in cylindrical shells, and the proposed theoretical models provide better understanding of vibration and wave propagation behaviors of cylindrical shells with smart materials and can be used to guide design and analysis of smart cylindrical shell structures.
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