In this presentation, frst, the Internal Damping (I.D.) phenomena and related theories that have been previously reported in the literature for Metal Matrix Composites (M.M.C.s) are reviewed briefly. Then, the paper is focused on the transient ID phenomena. Especially, it is shown that a broad Iow temperature peak appears in the low frequency internal damping (ID) spectra of aluminium based mic...

A d'Alembert-based solution of forced wave motion with internal and boundary damping is presented with the specific intention of investigating the transient response. The dynamic boundary condition is a convenient method to model the absorption and reflection effects of an interface without considering coupled PDE's. Problems with boundary condition of the form [Formula: see text] are not self-...

In this paper, the quality factor of thermo-elastic damping in an electro-statically deflected micro-beam resonator has been investigated. The thermo-elastic coupled equations for the deflected micro-beam have been derived using variational and Hamilton principles based on modified couple stress theory and hyperbolic heat conduction model. The thermo-elastic damping has been obtained discretizi...

We study the dynamics and evolution of Nambu-Goto strings in a warped spacetime, where the warp factor is a function of the internal coordinates giving rise to a ‘throat’ region. The microscopic equations of motion for strings in this background include potential and friction terms, which attract the strings towards the bottom of the warping throat. However, by considering the resulting macrosc...

/department of mechanical engineering Introduction Noise reduction is a key issue for High-tech and high precision instruments. To reduce the noise levels emitted by internal or external sources, porous materials can be used for acoustic shielding. The acoustic wave penetrates into the pore network, and part of its energy is dissipated as heat by viscous friction and thermal-elastic damping, ma...

This system arises from a model of the nonlinear thermoelastic coupled vibration structure with the clamped ends for simultaneously considering the medium damping, the viscous effect and the nonlinear constitutive relation and thermoelasticity based on a theory of non-Fourier heat flux laws. By considering the case where the internal (structural) damping is present, for 0≤ ι < 1, we show that t...

Timoshenko beam equations with external damping and internal damping terms and forcing terms are investigated, and boundary conditions (end conditions) to be considered are hinged ends (pinned ends), hinged-sliding ends, and sliding ends. Unboundedness of solutions of boundary value problems for Timoshenko beam equations is studied, and it is shown that the magnitude of the displacement of the ...