This article investigates the classical entropy generation in cooled slabs. Two types of materials are assumed for the slab: homogeneous material and FGM (functionally graded material). For the homogeneous material, the thermal conductivity is assumed to be a linear function of temperature,...

The critical region in a compositionally graded material occurs where the dominant phase ceases to percolate, and so is poorly treated by effective medium theories. To address this problem, equations for the size and effective scalar properties of that region are obtained from percolation theory.