Finite element analysis of thermal conductivities of unidirectional multiphase composites

A continuum modeling based on finite element method (FEM) is performed using three-phase representative volume element (RVE) to investigate the thermal conductivities of multiphase composites reinforced by carbon fibers. The selected RVE consists of carbon fiber, matrix and fiber/matrix interphase. A comprehensive study is carried out to examine the effects of interphase features such as thickness and material properties on the effective thermal conductivities of multiphase composites. Moreover, the effects of carbon fiber volume fraction, orientation, various types of arrangement, i.e., random, uniform and different functionally graded distributions, waviness as well as matrix material properties on the effective thermal conductivities of multiphase composites are examined. The FEM predictions are in good agreement with the results of other numerical simulations available in the literature. Also, the FEM results are compared with the composite cylinder assemblage approach results.