Investigation on influence of braid angle and boundary condition for impact response of triaxial braided composites with subcell model using solid elements

摘要

In this paper, a 2D carbon fibre triaxial braided composite in the solid element model was studied using the explicit finite-element code ANSYS/LS-DYNA. The widely used way to analyse triaxial braided composite is focus on a unit cell, and a unit cell was divided into six subcells. By changing subcell size and orientation angle, the finite element model with different braiding angle can be obtained. Four types of triaxial braided composite with bias angle 30°, 45°, 60°, and 75° respectively were modelled and impacted with an identical projectile with the same initial velocity. To investigate the boundary effect, the elastic boundary condition was simulated by spring element. Numerical results indicated that 60° bias angle braid composite exhibits more balanced stiffness and modulus distribution, which would contribute to postpone crack initiation. The numerical results also reveal that the boundary condition plays an important role in the impact process to some extent.