NUMERICAL STUDY ON IN-PLANE IMPACT DYNAMICS OF CONCAVE HONEYCOMB STRUCTURE WITH NEGATIVE POISSON'S RATIO

The in-plane impact dynamic performance of a variable angular curved concave side multi cell honeycomb structure with negative Poisson's ratio is studied numerically. The effects of the arc angle and of impact velocity on the deformation failure mode, on the dynamic response curve, on the energy absorption characteristics and on the platform stress characteristics of the structure are discussed. The study results show that rotational displacement occurs in the structure and the cells are distorted during the impact. The deformation of the structure is affected by the arc angle of the cell. When the arc angle is different, the structure has different in-plane impact failure modes. During the impact process, the stress-strain curve includes an initial stage, a stable stage and a locking stage, and finally the structure enters a compaction stage. The energy absorption rate and the platform stress of the structure are significantly affected by the impact velocity and by the arc angle of the cell.