Alleviation of Deformation of Cylindrical Shell Using Piezoelectric Rings

A methodology for alleviating the deformation of cylindrical shells has been developed. The basic idea is to use piezoelectric ring stiffeners bonded to the surface of the shell to stiffen and counteract the deformation caused by external loads such as gravity, internal pressure, and temperature change. The function of the piezoelectric ring stiffeners may be realized by their stiffening effects and, more importantly, through their electrically induced strains causing pressure on the surface of the shell. These strains can, at desirable locations, produce adjustable deformations in the opposite direction of the deformations caused by external loading. Conventional differential equations governing displacements of linearly elastic cylindrical shells are used. For computer simulation, a simply supported thin cylindrical shell having 18 piezoelectric ring stiffeners bonded to its outer surface along the length of the shell is considered. Deformations along two generatrices of the shell are computed to demonstrate the effect of alleviation. Since the deformation produced by an individual ring stiffener depends on the magnitude and polarity of the applied voltage, it is possible to counteract deformations caused by any other type of loading. The simulated results for illustration show that the deformation of cylindrical shells can be effectively alleviated.