On the Prediction of Effective Material Properties of Cellular Hexagonal Honeycomb Core

Abstract

Analytical expressions for the effective elastic properties of cellular hexagonal honeycomb core have been presented in this study. The elemental beam theory has been adopted for each component inside the ‘unit-cell’ to arrive at the different expressions for effective properties utilizing the strain energy concept. The length of the diagonal struts, vertical struts, and included angle, as well as the thickness of the struts have been kept as variable, so various forms of hexagonal honeycomb cellular structures can be investigated in this approach. Other conventional finite element approaches and numerical homogenization methods are rather time consuming to predict effective properties. Moreover, a change in basic cell configuration (i.e., depth) requires a complete new meshing and analysis. In comparison, the analytical approach presented here is simple and computes the effective properties in a fraction of the time that is required for FE analysis with a minimum change in the input file. The proper implementation of this method embedded in large quasi-static or impact dynamic simulations (where part of the structure could be modeled with detailed finite element mesh for cellular core that may initiate damage, and rest could be modeled with a single solid layer of equivalent material properties) would give high computational advantage, which is essential in large-scale aerospace modeling and simulation environment.