Effect of particle morphologies on the percolation of particulate porous media: A study of superballs

Particle morphology is a crucial factor of influencing the prediction of percolation threshold in the study of continuum percolation of particle systems. Previous works on the percolation of particle synthesis mainly focused on spheres, ellipsoids and spherocylinders. In this paper, the newly synthesized superballs which smoothly interpolate between octahedrons, spheres and cubes are introduced, and a simple contact detection algorithm for superballs is proposed. By combing Monte Carlo method and percolation theory, the continuum percolation of randomly orientated congruent overlapping superballs is investigated in detail. The global percolation threshold Psi(c), for superballs with shape parameter m in [0.5, +infinity) are obtained in terms of a finite-size scaling technique. Finally, an analytical approximation for percolation threshold Psi(c), of superballs is derived and verified by existing data from literature. It is found from the study that when the parameter m varies between 0.5 and 1.0, the percolation threshold Psi(c) significantly increases with the increasing m, whereas the value of m continues to increase from 1.0 to +infinity, Psi(c), tpc will gradually decrease. We hope this study can provide good guidance for the development of percolation theory about non -spherical particle packing systems. (C) 2018 Elsevier B.V. All rights reserved.