Numerical analysis of electrically conductive fillers of composites for aircraft lightning strike protection

Purpose: This paper aims to present a numerical analysis and comparison of two types of conductive fillers of polymeric composites subjected to lightning strikes. Design/methodology/approach: Two types of conductive fillers were considered in the developed numerical models of electrically conductive composites: carbon nanotubes and polyaniline. For these fillers, the representative volume elements were developed to consider distribution of the particles that ensures percolation and homogenization of the materials within the Eshelby-based semi-analytical mean-field homogenization approach. The performed numerical analyses allowed determination of effective volume fractions of conducting particles, resistivity and conductivity tensors, and finally the current density for the simulated materials subjected to lightning strike. Findings: The obtained results allowed for comparison of electrical conductivity of two simulated materials. It was observed that besides fair results obtained in the previous studies for intrinsically conducting polymers as fillers of composites dedicated for lightning strike protection, the composites filled with carbon nanotubes reveal much better conductivity. Practical implications: The presented simulation results can be considered as initial information for further experimental tests on electrical conductivity of such materials. Originality/value: The originality of the paper lies in the proposed design and simulation procedures of conductive composites as well as the comparison of selected composites dedicated for lightning strike protection as the most intensively developed materials for this purpose.