Study of guided wave propagation in a honeycomb composite sandwich plate in presence of a high-density core region using surface-bonded piezoelectric transducers

"Honeycomb Composite Sandwich Structure" (HCSS), is a novel material that has been adopted globally as a major structural component in aerospace, marine and automotive vehicles due to its high strength to weight ratio and high energy-absorption capability. In this study, a combined numerical and experimental study is carried out in an effort to understand the attributes of the propagating Guided Wave (GW) modes in the presence of a High-Density (HD) core zone in a HCSS. Owing to the complex structural characteristics, the GW propagation study in HCSS with HD-core zone inherently possesses many challenges. Therefore, Two Dimensional (2D) numerical simulations of wave propagation in the HCSS without and with HD-core region are accomplished using surface bonded Piezoelectric Wafer Transducers (PWTs). Results of the numerical study show that the presence of the HD core leads to substantial decrease in the amplitude and the group velocity of the output GW signal. In order to validate the results of the simulation, experiments were conducted, which shows good agreement between the experimental and numerical results is in all the cases considered. In order to study the effect of size of the HD core zone on the group velocity and the amplitude of the propagating wave modes, a parametric study is also carried out for a selected range of the HD core widths. It is observed that the group velocity and the amplitude of the received GW modes are just about inversely proportional to the HD core width.