MODELLING OF COMPOSITES WITH DIRECT FE2 - A MULTI-LEVEL FEM

Abstract

Traditionally FE² methods require at least two finite-element simulations (microscale and macroscale) to be run concurrently, which makes it computationally intensive and difficult to implement. A novel easy-to-implement method called Direct FE² is proposed, which requires only a single finite element simulation for both the micro and macro scales. This is achieved by implementing the micro-macro scale transition with interpolation (shape) functions using Multi–point constraints (MPCs). The features and libraries of any commercial FE software can be easily accessed along with the implemented method without any restrictions. The method is validated for 2D and 3D cases. Further, a composite laminate modelling methodology based on Direct FE² is introduced, which allows modelling composite laminates from homogeneous constituents directly. The response of continuous glass fibre reinforced polymer composite pipes to various loads - tension, bending and torsion-are simulated using Direct FE² and compared with pipe experiments performed on a Stewart-based platform.