The recent advances in photonics and laser instrumentation have been creating a favorable environment for thermal-based elastic wave generation techniques and their applications in various fields, such as nondestructive testing and smart structures. The main advantages of laser-based NDE include noncontact evaluation, freedom for complex surface geometry, high spatial and temporal resolution, easy access to cavities, and fast scanning. Two disadvantages are that the laser-based method requires a good physical understanding of thermoelastic wave propagation in solids, which is considerably more complicated than elastic wave propagation, and more complicated instrumentation needed for data collection. In an idealized solid, thermal energy is transported by two different mechanisms: by quantized electronic excitations, which are called free electrons, and the quanta of lattice vibrations, which are called phonons. These quanta undergo collisions of a dissipative nature, giving rise to thermal resistance in the medium. A relaxation time is associated with the average communication time between these collisions for the commencement of resistive flow. There are a number of optical methods available for elastic wave generation and detection. The most commonly utilized techniques include interferometric and noninterferometric techniques, optical heterodyning, differential interferometry, and time-delay interferometry. In the current work, a transfer matrix formulation including the second sound effect is developed for a thermoelastic layer. The second sound effect is included to eliminate the thermal wave travelling with infinite velocity as predicted by the diffusion heat transfer model, and, consequently, the immediate arrival of waves. Utilizing this formulation and the periodic systems framework, the attenuation and propagation properties of one-dimensional thermoelastic wave in both continuum and layered structures are studied. A perturbation analysis is carried out to study the behavior of propagation constants. Values of the attenuation factor, defined as the real part of the propagation constant, are obtained for thermoelastic solids under investigation. The reflection and transmission coefficients between half-spaces are also calculated. To clarify the link between the transformed (frequency-wave number) and the physical (temporal-spatial) domains, a number of numerical simulation results obtained through an FFT based transient analysis are generated and presented. The transient analysis is carried out for two bi-periodic layered structures. Strong localization of thermal wave predicted by the analysis in the transformed domain demonstrated in the time-special domain. The thermal wave localization predicted by the transformed domain analysis and its extent are demonstrated by these transient response results.

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