Adaptive Multi-Fidelity (AMF) modelling of damage in composites under Low-Velocity impact and compression after impact

Abstract

In this paper, the recently developed adaptive multi-fidelity (AMF) approach is extended for progressive damage analysis of composite laminate subjected to low-velocity impact (LVI) and compression after impact (CAI). This approach is more computationally efficient by utilizing a combination of low-fidelity shell elements and high-fidelity brick elements in a single concurrent model. A general set of criteria has been proposed to govern the transition of shell and brick elements from one to the other and vice versa, as dictated by the mechanics of damage evolution. When matrix cracks or interfacial delamination initiates, shell elements transit to brick elements and cohesive elements are inserted to capture the damage growth. The brick elements partitioned by non-critical cracks are reverted to smeared shell elements when the numerical crack density becomes saturated in a laminate. Geometrical non-linearity is adopted here to predict large deformation in the composite laminate for both implicit quasi-static and dynamic analyses. The performance of AMF models is benchmarked with high-fidelity models and experimental data reported in literature. The predicted results show reasonable agreement with experimental observation and high-fidelity models, and up to 51% improvement in computational efficiency is achievable.