Study on vibration characteristics of sandwich beam with BCC lattice core

In this study, the vibration characteristics of a sandwich lattice beam have been studied using an analytical approach and finite element(FE) analyses. In the analytical approach, a sixth-order partial differential equation for expressing the motion in terms of the transverse displacement has been solved, which is assumed that the sandwich core is deformed mainly by the shear load. Here, a new theoretical approach for predicting the equivalent shear modulus G_C^∗ of the lattice core is proposed. The analytical prediction of the natural frequency, accounting for transverse shear, agrees well with the FE results. Also, the vibration response of the first-order natural frequency f₁ exhibits a upwardly convex curve as the strut diameter increases, suggesting that there is a maximum value of the frequency f₁ for a given facesheet thickness t_f. Moreover, it is observed that the maximum frequency of the sandwich lattice beam is always greater than that for a continuum beam, which ensures the effectiveness of the lattice core in enhancing the vibration response. Therefore, vibration suppression in aircraft structures can be achieved by introducing lattice sandwich panels.