The importance of thermoelastic damping as a fundamental dissipation mechanism for small-scale mechanical resonators is evaluated in light of recent efforts to design high-Q micrometer- and nanometer-scale electromechanical systems. The equations of linear thermoelasticity are used to give a simple derivation for thermoelastic damping of small flexural vibrations in thin beams. It is shown that Zener’s well-known approximation by a Lorentzian with a single thermal relaxation time slightly deviates from the exact expression.

Thermoelastic Damping in Micro- and Nano-Mechanical Systems.

The present article intends to provide a size-dependent generalized thermoelasticity model and closed-form solution for thermoelastic damping (TED) in cylindrical nanoshells. With the aim of incorporating size effect within constitutive relations and heat conduction equation, nonlocal elasticity theory and Guyer–Krumhansl (GK) heat conduction model are exploited. Donnell–Mushtari–Vlasov (DMV) equations are also employed to model the cylindrical nanoshell. By adopting asymmetric simple harmonic form for oscillations of nanoshell and merging the motion, compatibility and heat conduction equations, the nonclassical frequency equation is extracted. By solving this eigenvalue problem and separating the real and imaginary parts of complex frequency analytically, an explicit expression is given to estimate the magnitude of TED in cylindrical nanoshells with arbitrary boundary conditions. Good agreement between the results of this study in special cases and those available in the literature affirms the validity of present formulation. In the following, for some vibration modes, a detailed parametric study is conducted to illuminate the determining role of structural and thermal nonlocal parameters in the amount of TED in simply-supported cylindrical nanoshells. The augmentation of difference between classical and nonclassical results by reduction in dimensions of nanoshell confirms the small-scale effect on TED value at nanoscales. • A closed-form expression for evaluating the amount of thermoelastic damping (TED) in cylindrical nanoshells is given. • The nonlocal elasticity theory and the Guyer-Krumhansl (GK) heat conduction model are used. • Comparison studies are conducted to check the validity of presented formulation. • Parametric studies are done on the results given by classical and nonclassical continuum theories and heat transfer models. • Detailed numerical results are provided to survey the effect of some parameters like vibration mode on TED value. 

Generalized thermoelasticity model for thermoelastic damping in asymmetric vibrations of nonlocal tubular shells

Analytical and parametric analysis of thermoelastic damping in circular cylindrical nanoshells by capturing small-scale effect on both structure and heat conduction

Forced and free vibrational analysis of viscoelastic nanotubes conveying fluid subjected to moving load in hygro-thermo-magnetic environments with surface effects

Thermoelastic damping in circular microplate resonators based on fractional dual-phase-lag model and couple stress theory

This paper assesses thermoelastic damping (TED) in circular nanoplates by incorporation of the small-scale effect into structural and thermal domains. The nonlocal elasticity theory and dual-phase-...

YouYu Mo

Papers

Size-dependent generalized thermoelasticity model for thermoelastic damping in circular nanoplates