A new method is proposed to consider the characterizations of the fillers in overall properties of heterogeneous media, and in particular, nanocomposites. According to this method, named ‘Hybrid averaging,’ the effective properties of a general nanocomposite containing several phases and orientations can be found using the results from a number of simple unidirectional two-phase nanocomposites. The results for the simple media might be obtained from any roots including analytical approaches, numerical simulations, and experimental analyses. In this article, M—T as the analytical and FE as the numerical approaches are combined with the proposed hybrid method. To perform FE analysis, RRVE with periodic boundary conditions is employed. In addition, the influential parameters consisting of RRVE size and mesh density on the numerical results are justified by satisfying certain criteria. Numerical investigations are then done for two case studies of nanocomposites in which boron nitride nanotubes, as fillers, are distributed using two different functions. Furthermore, comparisons are made between the results obtained from different approaches for these materials.
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