On the Lewis–Nielsen model for thermal/electrical conductivity of composites

Several models have been proposed in the literature to describe the thermal and electrical conductivities of particulate composites. Among the proposed models, the Lewis–Nielsen model appears quite attractive as it is simple to use and it predicts the correct behavior when filler concentration (ϕ) approaches the maximum packing concentration (ϕm). In this paper, the Lewis–Nielsen model is evaluated in light of a vast amount of experimental data available on thermal and electrical conductivities of particulate composites. The Lewis–Nielsen model is found to describe the experimental data for both thermal and electrical conductivities reasonably well.