Evaluating the performance of microstructure generation algorithms for 2-d foam-like representative volume elements

This investigation evaluates various numerical algorithms; each designed to generate periodic 2-D Representative Volume Elements (RVEs) containing foam-like microstructures suitable for direct import into commercial finite element software for mechanical evaluation. The operation of each algorithm is discussed and the resulting RVEs are examined from both a mechanical and a morphological perspective. A basic Voronoi-based algorithm is found to be simple to implement but the method is shown to produce inherently anisotropic microstructures. Increasing the degree of irregularity of the microstructure reduces the anisotropy but at the cost of creating unrealistic microstructures, containing highly angular cells. A method of modifying such unrealistic microstructures using a centroidal tessellation relaxation algorithm is demonstrated, ultimately producing RVEs with relatively realistic mono-disperse microstructures. An alternative algorithm is also investigated the advantage of this algorithm is its ability to generate poly-disperse microstructures, with a controllable degree of poly-dispersity and an almost fully isotropic mechanical response. (C) 2016 The Authors. Published by Elsevier Ltd.