EFFECTS OF THERMOMECHANICAL COUPLING AND RELAXATION-TIMES ON WAVE SPECTRUM IN DYNAMIC THEORY OF GENERALIZED THERMOELASTICITY

A spectral study is performed to gain insight into the effects of rela xation times and thermomechanical coupling on dynamic thermoelastic re sponses in generalized thermoelasticity. The hyperbolic thermoelastic theories of Lord and Schulman (LS) and Green and Lindsay (GL) are sele cted for the study. A generalized characteristic equation is derived t o investigate dispersion behavior of thermoelastic waves as functions of thermomechanical coupling and relaxation time constants. Thermomech anical coupling is found to impose a significant influence on phase ve locities. The GL model implicitly indicates that the order of magnitud e of the thermomechanical relaxation lime can never be greater than th at of thermal relaxation time.