3-D Finite element models for the prediction of effective transverse thermal conductivity of unidirectional fibre reinforced composites

Applicability of the finite element model (FEM) in predicting the effective transverse thermal conductivity (k₂) of the unidirectional fibre reinforced composites is systematically studied. 3-D finite element models for the array of square and hexagonal unit cells of long circular cylinder with appropriate thermal boundary conditions are developed. FEM software ANSYS 10.0 is successfully executed and the effective transverse thermal conductivity is evaluated for various fibre volume fractions (V_f). The results are validated with the experimental and analytical results available in the literature and found to be quite coherent. The developed models are found suitable in accurately predicting k₂ at all values of V_f in the range and thus eliminate the complexity of developing different analytical expressions for different range of V_f. The methods such as analytical and 2-D FEM developed so far fails in accommodating fibre anisotropy and, imperfections in matrix, fibre and fibre-matrix interface. The present models are capable of predicting k2 in all the above cases. Finally transverse effective thermal conductivities are evaluated for P120 and E-Glass with a range of matrix thermal conductivity values using both models and results are presented.