Double diaphragm forming simulation using a global-to-local modelling strategy for detailed defect detection in large structures

A global-to-local modelling strategy is presented based on a sub-modelling approach to predict the formation of macroscale defects in bi-axial non-crimp fabric (NCF) during double diaphragm forming (DDF). full-scale global simulation initially performed using coarse membrane element mesh (5 mm edge length) locate areas containing potential defects. Refined local simulations are subsequently high fidelity shell-element (1 explicitly shape induced these areas, boundary conditions derived from simulation. The methodology validated by blank over generic geometry comprising changes cross-sectional shape, order invoke controlled manner. defective predicted agree well with locations observed experiments, including and length surface visible such as wrinkling bridging. CPU time for this two-stage shown be approximately 13% compared required model same geometry.