Size-dependent analysis of thermoelastic damping in electrically actuated microbeams

Abstract

This paper presents an analytical expression for the thermoelastic damping (TED) in electrically actuated microbeams based on the nonclassical continuum theory of the modified couple stress (MSC) and the nonclassical heat conduction model of the dual-phase-lag (DPL). This expression for TED captures small-scale effects. The coupled equations of motion and heat conduction are first derived. Then, the set of coupled governing equations are analytically dealt, and the real and imaginary parts of frequency are extracted in the framework of the complex frequency approach. Next, a closed-form relation for describing TED in electrically actuated microbeams is obtained which captures the small-scale effects. In some case studies, numerical results are presented to investigate the dependence of the amount of TED on the applied voltage and boundary conditions in the presence of small-scale effects, and some of these results are compared with those based on the classical continuum theory, in which the small-scale effects are ignored.