Dynamic response of foam sandwich structures under multiple ice projectiles impacts at high velocity

Hail presents a significant threat to the structural integrity of aircraft, particularly with the extensive use of foam sandwich structures in aerospace applications. Therefore, it is crucial to consider the effects of hail impact on foam sandwich structures. This paper aims to investigate the impact of ice projectiles on carbon Fiber/PMI foam sandwich structures, using both experimental and numerical simulation approaches. The gas cannon was employed to launch ice projectiles, which were then directed towards the carbon Fiber/PMI foam sandwich structures. Additionally, a numerical simulation model was developed using ANSYS/LS-DYNA software to analyse the impact of these ice projectiles. Moreover, the validity of the finite element model was confirmed through experimental verification. The study involves simulations of single-point continuous impacts of ice projectiles and multi-point simultaneous impacts on carbon Fiber/PMI foam sandwich structures, while maintaining the same total impact energy. By varying the distribution of ice projectiles, the dynamic response and damage characteristics of the target plate are analysed. Specifically, the research aims to investigative the deformation characteristics of the target plate and the energy absorption of the structure. The research results underscore the importance of considering the distribution of ice projectiles in mitigating structural damage caused by hail impact.