Finite-element analysis of the fundamental frequency of a sandwich plate with pyramidal lattice truss core: Comparison of the discrete and continuous core models

This paper presents a comparative analysis of discrete and continuous models for the pyramidal lattice truss core in sandwich plates. The study focuses on determining the fundamental vibration frequency as the basis for model comparison. The finite element method, implemented in ANSYS, was employed to address the dynamic problem. The sandwich plate with a pyramidal lattice truss core was modeled using shell and beam finite elements, while the continuous core plate was represented with shell and solid volume finite elements. The effects of the number of pyramidal cells, core thickness, and lattice truss core strut diameter on the fundamental frequency were examined. Fundamental frequencies obtained from both core models were compared, revealing that the continuous core model consistently overestimates the fundamental frequency. Additionally, a design algorithm for sandwich plates with a pyramidal lattice truss core was developed. The procedures for finite element model generation, fundamental frequency calculation, and structural design were implemented using APDL.