Hygro-mechanical vibration analysis of a rotating viscoelastic nanobeam embedded in a visco-Pasternak elastic medium and in a nonlinear thermal environment

摘要

The vibration behavior of the rotating viscoelastic nanobeam embedded in the visco-Pasternak foundation is studied. The governing equation is extracted by using the surface elasticity and the nonlocal elasticity theory. The influence of the humidity on the vibration frequencies of the viscoelastic nanobeam is investigated in the thermal environment. The effects of the linear and the nonlinear thermal stress cases on the vibration frequencies of the viscoelastic nanobeam are studied. The vibration frequencies are obtained based on the differential quadrature method. Also, the numerical results are compared with those which are reported in the literature, and a good correlation is obtained. The results are presented for the different boundary conditions as well as the effect of the torsion spring on the viscoelastic nanobeam ends is investigated. This study focuses on the combined effects of the angular velocity, the internal and external damping, the humidity change, the temperature change, the surface effects (surface density, surface elasticity and surface stress), the nonlocal parameter, the boundary conditions, the visco-Pasternak foundation, the cross section geometry, and the torsion spring. The results of this study could be used to design and manufacture nanosensors, biosensors, atomic force microscope and the NEMS/MEMS devices.