Effect of viscous-Pasternak foundation on laser-excited microbeams via modified thermoelastic MGT model

Abstract

Due to the wide variety of applications in many fields of science and engineering, the subject of foundations is considered highly attractive to many investigators. Foundations are also essential in maintaining microstructural systems during oscillations. In the current paper, a modified model of a microbeam resting on a viscous Pasternak foundation under the influence of axial tension will be presented. The microbeam is described as an Euler-Bernoulli beam as it was heated by a very short laser pulse. Based on the Moore-Gibson-Thompson (MGT) model of non-Fourier-heat-conduction and thermal field effect, the equation governing the vibration of the thermoelastic microbeam was derived. An analytical solution is presented for the studied field variables based on the Laplace transform method, in addition to an approximate numerical technique for calculating inverse transformations. The effects of different effective factors on the deflection, temperature, and thermal stresses are demonstrated, including viscoelastic damping structures, damping coefficients, laser pulse heating, and stiffness of the viscoelastic substrate. Furthermore, the estimated outcomes are compared with those obtained in the previous literature to ensure that the derived formulas are acceptable. Additional numerical results are summarized in the tables and presented graphically in order to make comparisons and reveal the effect of all effective thermal parameters. Finally, the importance of the thermo-elastic MGT model over the previous corresponding models was explored.