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

Abstract

Impacts on composites produce interlaminar failure (delamination) which is difficult to detect in commonmaintenance tasks, and affects the structural integrity. Therefore it is critical, for safety, to improve predic-tion tools in order to perform tolerant damage designs. The numerical modeling of impacts of deformableobjects (such as ice) on composite panels is still a challenge. Not only the modeling of the laminate shouldbe appropriate to reproduce its behavior and failures, but also the modeling of the deformable projectileshould be capable to induce the corresponding response and damages. In this work a two-step numericalmethodology is proposed for the study of ice impact. First, the deformable impactor is analyzed, studyingthe impact process on a rigid target (a steel plate attached to a load cell). Once the deformable projectilebehavior is fully captured, the ice impact on a deformable target (a carbon/epoxy laminate) is studied. Thecomposite material model takes into account intralaminar and interlaminar failure in order to reproduce thelaminate 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 theexperimental results.