Prediction the Radial Natural Characteristic of Sandwich Spherical Shell Based on Wave Propagation

In this work, the natural characteristic of elastic sandwich spherical shell subjected to radial excitation is systematically analyzed and evaluated based on wave propagation.

Initially, the transfer matrix corresponding to radial vibration is derived and applied to conventional fundamental solution method for capturing the characteristic equation of natural frequency of sandwich spherical shell. Then, based on the theory of elasticity, the propagation, reflection and coordination matrices are assembled to investigate the natural characteristic. In order to illustrate the validity of the proposed method, the natural frequencies predicted by wave approach are compared with the conventional fundamental solutions. Finite Element Method (FEM) is carried out to validate the theoretical results. Simultaneously, natural frequencies of sandwich spherical shell with free-free and clamped–clamped boundary constraints are investigated.

A numerical example is further presented to demonstrate the accuracy and validity of the proposed wave approach by comparing the present results with the available published data.

It is shown that the proposed wave approach is accurate and valid in capturing the resonance frequencies.