Permittivity of lossy composite materials

摘要: An ab initio numerical simulation model has been used to compute the complex effective dielectric constant of a two-component lossy composite material, in quasistatic limit. A computational algorithm with conventional finite element formulation solves Laplace’s equation for spatially heterogeneous medium, using field calculation package FLUX3D. In this way, different three-dimensional topological arrangements components were considered. The material consists dense spheres uniform size that are arranged simple, body-centered, and face-centered cubic lattices. accuracy method is checked by comparing results previously presented literature. Detailed predictions provide comparison percolation theory when imaginary part relative permittivity very large. McLachlan’s generalized medium [D. S. McLachlan, J. Phys. C 20, 865 (1987)] further provided over wide range conditions. From these calculations one can conclude there significant discrepancies between evaluated values those obtained on basis analysis. On hand, demonstrated here shows real permittivity, from results, be significantly predicted inclusion large compared its part. other capture trends threshold variation lattice packing. We measured exponents s t which determine how parts scales distance threshold. This behavior most probably due drastic differences basic assumptions existing modeling our approach. particular, analysis makes it clear any approach based only dipole approximation must fail correctly describe constant, entire volume fraction spherical inclusions.