A global nonlinear stability analysis is performed for a couple-stress fluid layer heated from below saturating a porous medium with temperature-pressure dependent viscosity for different conducting boundary systems. Here, the global nonlinear stability threshold for convection is exactly the same as the linear instability boundary. This optimal result is important because it shows that lineari...

In this paper, the size dependent behavior of the gold micro-switches has been studied. This behavior becomes noticeable for a structure when the characteristic size such as thickness or diameter is close to its internal length-scale parameter. The size dependent effect is insignificant for the high ratio of the characteristic size to the length-scale parameter, which is the case of the silicon...

Modified couple stress theory is applied to study of temperature effects on free vibration of Timoshenko functionally graded microbeams. Due to the interatomic and microstructural reactions of the structures in micro scale, the dynamic behavior of the microbeam is predicted more accurate applying the couple stress theory. Both of the simply supported and clamped boundary conditions are assumed ...

The present investigation deals with study of thermoelastic damping and frequency shift of Kirchhoff plate resonators by using generalized thermoelasticity theory of dual-phase-lag model. The basic equations of motion and heat conduction equation are written with the help of Kirchhoff-Love plate theory and dual phase lag model. The analytical expressions for thermoelastic damping and frequency ...

The present study investigates the buckling of a thick sandwich plate under the biaxial non-uniform compression using the modified couple stress theory with various boundary conditions. For this purpose, the top and bottom faces are orthotropic graphene sheets and for the central core the isotropic soft materials are investigated. The simplified first order shear deformation theory (S-FSDT) is ...

in this paper, the flow of couple stress fluid is investigated in a helical screw rheometer (hsr). by unwrapping the channel, lands, and the outside rotating barrel, the geometry of hsr is approximated as a shallow infinite channel. both one- and two-dimensional analysis of the problem is presented using rectangular coordinates. in either case an exact solution of the flow problem is presented ...

In present paper, vibration of Nano FGM plate based on modified couple stress and First Order Shear Deformation Theories (FSDT) under moving load has been developed. Basic equations and linear strains are introduced by first order shear deformation theory and Mori Tanaka’s model is used for the plate. The module of elasticity and density are assumed to vary only through thickness of plate. Gove...

As an extension to strain-gradient models of size-dependent plastic behaviour, this work proposes a model for stress-gradient theory. The is distinguished from earlier works on the topic by its being embedded in thermodynamically consistent framework. development carried out context single-crystal plasticity, and draws conventional plasticity. explored numerically using example torsion thin wir...