Assessment of dynamic characteristics of thin cylindrical sandwich panels with magnetorheological core

Abstract

Based on the equivalent single-layer linear theory for laminated shells, free and forced vibrations of thin cylindrical sandwich panels with magnetorheological core are studied. Five variants of available magnetorheological elastomers differing in their composition and physical properties are considered for smart viscoelastic core. Coupled differential equations in terms of displacements based on the generalized kinematic hypotheses of Timoshenko accounting for transverse shears with coefficients depending on the complex shear modulus for a smart core are used to govern vibrations of cylindrical panels. Assuming conditions of simple support for straight and curvilinear edges, solutions in the explicit form describing natural modes as well as an equation with respect to the required complex eigenfrequencies are found. To predict the shell response to an external harmonic force, the general solution of non-homogeneous governing equations is derived in the form of series in natural modes. To estimate damping capability of magnetorheological elastomers under consideration, the principle tunable parameters, the lowest natural frequencies and associated logarithmic decrements are calculated for the same panels with different magnetorheological elastomers under the action of a magnetic field of different intensities. Finally, the amplitude–frequency plots for magnetorheological elastomer-based panels of different opening angles with and without magnetic field are presented.