Numerical methodology to analyze the ice impact threat: Application to composite structures

Highlights: • Ice material model widely validated for impacts onto different kinds of structures • Development of a numerical methodology for soft body impactors • Simplified composite model capable to reproduce the overall effects of ice sphere impacts Impacts on composites produce interlaminar failure (delamination) which is difficult to detect in common maintenance tasks, and affects the structural integrity. Therefore it is critical, for safety, to improve prediction tools in order to perform tolerant damage designs. The numerical modeling of impacts of deformable objects (such as ice) on composite panels is still a challenge. Not only the modeling of the laminate should be appropriate to reproduce its behavior and failures, but also the modeling of the deformable projectile should be capable to induce the corresponding response and damages. In this work a two-step numerical methodology is proposed for the study of ice impact. First, the deformable impactor is analyzed, studying the impact process on a rigid target (a steel plate attached to a load cell). Once the deformable projectile behavior is fully captured, the ice impact on a deformable target (a carbon/epoxy laminate) is studied. The composite material model takes into account intralaminar and interlaminar failure in order to reproduce the laminate behavior. Different ice sphere diameters (30,40 and 50mm) and impact velocities (50 − 250m/s) are considered in this study. All the results from the numerical simulations have been compared with the experimental results.