Calculation of the thermal conductivity of randomly dispersed composites using a finite element modelling method

A new method to generate 3 dimensional finite element method (FEM) models of composites with random materials arrangement has been proposed. Some basic models are used to represent the structure of the composites, in each basic model, the dispersions are assumed to have the same geometry, and the structure of a basic model can be described by some structural parameters such as the geometry, number and volume fraction of the dispersion and so on. A program has been developed to automatically generate the geometric model and FEM mesh of the basic models according to given structure parameters. More complicated composite structure can be composed by combination of the basic models. The effective thermal conductivity of composite has been calculated based on the models generated with this method. Optimization of modeling parameters such as model scale and mesh refinement has been discussed with consideration of both calculation accuracy and computation efficiency. The calculated thermal conductivity has been compared to the values obtained by analytical method.