PLANE HARMONIC WAVES IN A MICROPERIODIC LAYERED THERMOELASTIC SOLID REVISITED

摘要

In previous work a one-dimensional averaged theory of thermoelastic waves in a microperiodic layered infinite solid was proposed in which an eighth-order-in-time partial differential equation involving a high intrinsic mechanical frequency Ω_M and a high intrinsic thermal frequency Ω_T is a central equation. Also, the existence of two harmonic thermoelastic waves of a given frequency ω propagating in a positive direction normal to the layering was previously established when Ω_M → ∞ and Ω_T < ∞, or Ω_M < ∞ and Ω_T → ∞. The existence of two harmonic thermoelastic waves of a given frequency ω propagating in the positive direction normal to the layering is proved when Ω_M < ∞ and Ω_T < ∞. Also, a closed form of the associated velocities and attenuation coefficients is obtained. Numerical results illustrating propagation of the two waves in a particular microperiodic layered thermoelastic solid are included.