Percolation Thresholds Through the Voids Around Randomly Oriented Faceted Barrier Particles

Realistic porous materials are often made up of randomly oriented impermeable particles with fluid transport occuring through the voids. Transport is hindered with increasing concentration of barrier particles, ultimately ceasing at the percolation transition. Using a dynamical approach involving virtual tracer particles which explore and determine the extent of the voids, we have calculated percolation thresholds for a variety of included particles, having in common random orientations and angular, faceted shapes. In this regard we consider fractured spheres (e.g. hemispheres and tabular sections), polygonal and circular plates, and polyhedra such as tetrahedra and cubes. By considering asymmetrical particles with dipole moments that could respond to an electric field in a temperature dependent situation, we explore the continuum between uniformly and randomly oriented assemblies of barriers. In particular, we determine if the anisotropy due to the field induced alignment leads to distinct percolation thresholds perpendicular and parallel to the applied field.