/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...

We show that the coupled balance equations for a large class of dissipative materials can be cast in the form of GENERIC (General Equations for Non-Equilibrium Reversible Irreversible Coupling). In dissipative solids, also called generalized standard materials, the state of a material point is decribed by dissipative internal variables in addition to the elastic deformation and the temperature....

contains the elasticity modules of the medium. Usually one makes the assumption that S is positive definite such that A(D) is a positive and self-adjoint operator. Then the first equation is hyperbolic, while the second one is parabolic. In [2] the thermo-elastic system is considered and dispersive estimates are proven under the assumptions that (A1-2) A(ξ) is positive (self-adjoint, 2-homogene...

This article provides a fully analytical approach for nonlinear equilibrium path of rectangular sandwich plates. The core of structure is made of symmetric cross-ply laminated composite and the outer surfaces are piezoelectric actuators which perfectly bonded to inner core. The structure is subjected to electro-thermo-mechanical loads simultaneously. One side of plate is rested on Pasternak typ...

In this research, static stresses analysis of boron nitride nano - tube reinforced composite (BNNTRC) cylinder made of poly - vinylidene fluoride (PVDF) subjected to non - axisymmetric thermo - mechanical loads and applied voltage is developed. The surrounded elastic medium is modelled by Pasternak foundation. Composite structure is modeled based on piezoelectric fiber reinforced composite (PFR...

One of the most promising materials in nanotechnology such as sensors, actuators and resonators is annular Boron Nitride sheets (ABNSs) due to excelled electro-thermo-mechanical properties. In this study, however, differential quadrature method (DQM) and nonlocal piezoelasticity theory are used to investigate the nonlinear vibration response of embedded single-layered annular Boron Nitride shee...

The general solution of the equations for a homogeneous isotropic microstretch thermo elastic medium with mass diffusion for two dimensional problems is obtained due to normal and tangential forces. The Integral transform technique is used to obtain the components of displacements, microrotation, stress and mass concentration, temperature change and mass concentration. A particular case of inte...

An alloy for musical instruments should have high enough strength, hardness, specific elastic properties and low damping capacity. The high tin bronze alloys with composition 20-22 wt.% Sn has good acoustical properties, which is capable of producing long-lasting slowly damping vibrations but there is brittle materials. Cracks and fracture may appear on these materials. The study on mechanical ...

The governing equations of an initially stressed, rotating and transversely isotropic thermoelastic solid permeated with magnetic field are solved for surface wave solutions. The appropriate particular solutions in the half-space satisfy the required boundary conditions at a thermally insulated stress free surface. A velocity equation is obtained for wave speed of thermo-elastic Rayleigh wave. ...