Coupled thermoelastic analysis of a multi-layered hollow cylinder based on the C-T theory and its application on functionally graded materials

The coupled thermoelastic behavior of a multi-layered or functionally graded hollow cylinder under generally transient thermal and mechanical loadings is investigated in this paper. The generalized Chandrasekharaiah-Tzou (C-T) thermoelasticity theory, based on the dual-phase-lag hyperbolic heat conduction model, is used to describe the nature of finitely thermal and elastic wave speeds. The Kapitza thermal interface model indicates that the temperature can jump across the interface but the heat flux in the radial direction is continuous. With the Laplace transform method eliminating the time-dependence of the coupled partial differential equations, the problem is theoretically solved by introducing a displacement potential function. A numerical Laplace inversion technique is then employed to transform the results into the time domain. Finally, the effect of heat conduction models, inertial and coupling effects, loading types, interfacial imperfection, Biot number, and functionally graded profiles on the thermal and elastic results is analyzed. Also, the physically unrealistic discontinuity in displacement is observed when the cylinder is subjected to a Dirac delta-type thermal loading.