Some Investigations of Effective Thermal Conductivity of Unidirectional Fiber-Reinforced Composites

Abstract

The effective thermal conductivity of a unidirectional composite was determined. Inner structure of the composite was approximated by symmetric, rectangular arrangement of fibers. The composite thermal con ductivity was calculated with the use of different theoretical methods and compared to experimental data obtained from a model of the composite and the composite itself. Good agreement was found between theory and experiment. Temperature fields in the composite were also calculated. The results of the effective thermal conductivity occurred to be lower than the analogical values obtained by Adams and Doner. It was found that for isotropic composite having up to 50% fiber volume fraction, Hashin and Rosen's formula for "random arrangement" of fibers could be successfully used. Two pairs of bounds on the composite thermal conductivity were studied. Each of them was found to be narrower for different range of fiber volume fraction.

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