TY - JOUR
T1 - Geometrical percolation threshold of overlapping ellipsoids
AU - Garboczi, E. J.
AU - Snyder, K. A.
AU - Douglas, J. F.
AU - Thorpe, M. F.
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 1995
Y1 - 1995
N2 - A recurrent problem in materials science is the prediction of the percolation threshold of suspensions and composites containing complex-shaped constituents. We consider an idealized material built up from freely overlapping objects randomly placed in a matrix, and numerically compute the geometrical percolation threshold pc where the objects first form a continuous phase. Ellipsoids of revolution, ranging from the extreme oblate limit of platelike particles to the extreme prolate limit of needlelike particles, are used to study the influence of object shape on the value of pc. The reciprocal threshold 1/pc (pc equals the critical volume fraction occupied by the overlapping ellipsoids) is found to scale linearly with the ratio of the larger ellipsoid dimension to the smaller dimension in both the needle and plate limits. Ratios of the estimates of pc are taken with other important functionals of object shape (surface area, mean radius of curvature, radius of gyration, electrostatic capacity, excluded volume, and intrinsic conductivity) in an attempt to obtain a universal description of pc. Unfortunately, none of the possibilities considered proves to be invariant over the entire shape range, so that pc appears to be a rather unique functional of object shape. It is conjectured, based on the numerical evidence, that 1/pc is minimal for a sphere of all objects having a finite volume.
AB - A recurrent problem in materials science is the prediction of the percolation threshold of suspensions and composites containing complex-shaped constituents. We consider an idealized material built up from freely overlapping objects randomly placed in a matrix, and numerically compute the geometrical percolation threshold pc where the objects first form a continuous phase. Ellipsoids of revolution, ranging from the extreme oblate limit of platelike particles to the extreme prolate limit of needlelike particles, are used to study the influence of object shape on the value of pc. The reciprocal threshold 1/pc (pc equals the critical volume fraction occupied by the overlapping ellipsoids) is found to scale linearly with the ratio of the larger ellipsoid dimension to the smaller dimension in both the needle and plate limits. Ratios of the estimates of pc are taken with other important functionals of object shape (surface area, mean radius of curvature, radius of gyration, electrostatic capacity, excluded volume, and intrinsic conductivity) in an attempt to obtain a universal description of pc. Unfortunately, none of the possibilities considered proves to be invariant over the entire shape range, so that pc appears to be a rather unique functional of object shape. It is conjectured, based on the numerical evidence, that 1/pc is minimal for a sphere of all objects having a finite volume.
UR - http://www.scopus.com/inward/record.url?scp=0000975565&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0000975565&partnerID=8YFLogxK
U2 - 10.1103/PhysRevE.52.819
DO - 10.1103/PhysRevE.52.819
M3 - Article
AN - SCOPUS:0000975565
VL - 52
SP - 819
EP - 828
JO - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
JF - Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
SN - 1539-3755
IS - 1
ER -