Free and Random Vibration Analysis of Concave Honeycomb-Filled Strengthened Corrugated Core Sandwich Panels under Various Constraints

This work introduces a new type of concave honeycomb-filled strengthened corrugated core sandwich panel and studies its structural vibration performance. Using homogenization and finite element methods, the present work derived the equivalent macroscopic stiffness of the concave honeycomb-filled strengthened corrugated core and established a corresponding two-dimensional (2D) equivalent model. To examine the vibrational behavior of the sandwich panel under various constraints, experimental tests and three-dimensional (3D) numerical simulations were carried out. Both free and random vibration responses were studied. The effects of different boundary conditions (BCs) on natural frequencies, mode shapes, power spectral density (PSD), root mean square (RMS) response, and effective mass fraction (EMF) are discussed. The model’s accuracy and reliability were validated by comparing experimental and 2D and 3D numerical simulation results. The relative error between the free and random vibrations is less than 10%. Finally, adjusting the geometric parameters of the individual units in the concave honeycomb-filled strengthened corrugated core fixture revealed that the natural frequency, displacement, and RMS response exhibit different sensitivities to the geometric parameters of the corrugated and concave honeycomb structures.