Longitudinal Heat Propagation in Three-Phase Laminated Composites at Low Exciting Frequencies

In order to explore the behavior of matrix-filler bilaminate MFMFM… near the interfaces it is necessary to augment it into a trilaminate MBFBMBF… arrangement (of volume fractions f_M, f_B, f_F), and then consider the condition that the binder layer is infinitely thin, f_B → 0. In a previous paper [1] the problem was considered for high frequencies ω of the boundary temperature excitation T(0, y, t) = e^−iwtχ(y), using power series representation for the eigenvalues descending in ω^1/2 powers. In the first part of the present paper the low frequency regime is determined, using eigenvalue expansions in ascending powers of ω. The second part of the paper is devoted to exhibiting the interface layer as a shock layer across which there occur temperature jump and flux jump, of unexpected nature.