Cutting energy absorption property analysis and homogenization analysis of combined honeycomb subject to explosive loading

Abstract

Limited studies were reported about energy absorption characteristics of combined honeycombs subjected to uniformly distributed explosive loading in air. In this paper, the cutting strain of the combined honeycomb core considering the effects of core diameter, explosive charge mass and scaled distance was first investigated through air explosion experiments. A full-scale finite element (FE) model and a homogenization method were then proposed and verified by comparing the numerical solutions with the experimental results. Based on the FE model, the individual effects of the peak overpressure and positive impulse on the cutting performance were revealed. The experimental results demonstrated that either a decreasing scaled distance or an increasing charge mass resulted in a larger cutting strain. The numerical solutions indicated that similar changing tendencies to cutting strain were observed for the cutting plateau stress and energy absorbed by the combined honeycomb. Based on the dimensional analyses, a semi-empirical formula was proposed for predicting the relationship between the absorbed energy and cutting plateau stress. In addition, a deformation mode map was developed. The map plotted the peak overpressure vs. the impulse and identified the dominant deformation mode for each application point in this space. The map can be used in combination with the semi-empirical formula, and then the cutting performance of the combined honeycomb can be determined easily and quickly.