On the generalized self-consistent model for the effective thermal conductivity of composites reinforced by multi-layered orthotropic fibers

In this paper, a generalized self-consistent model (GSCM) is developed to predict the effective thermal conductivity of composites reinforced with multi-cladded cylindrically orthotropic fibers. For generalizing the formulation, the interfacial thermal contact resistances of the fibers' cladding layers are also considered. Using the GSCM, a very explicit expression of the effective thermal conductivity is derived in terms of the orthotropic conductivities of each cladding layer, interfacial contact resistances, and the volume fraction of fibers. For the special case when bare homogeneous fibers are considered, the degenerated formulation turns out to agree with an existing theoretical solution. Providing further comparisons for a few more general cases with varied parameters, the GSCM results are also in excellent agreements with some numerical results presented in the literature. Our analyses show that the proposed GSCM model can accurately predict the effective thermal conductivity of composites reinforced with cylindrically orthotropic inhomogeneous fibers with interfacial thermal resistance. Additionally, the local thermal field of such composites can also be evaluated using the present model.