Analysis of a curved Timoshenko nano-beam with flexoelectricity


A Timoshenko beam model is applied for the analysis of the flexoelectric effect for a curved nano-beam. This theory transforms the beam to a 1-d problem along the beam axis. The electric intensity vector for the open-circuit condition can be expressed by mechanical quantities, namely strains and strain gradients. The variational principle is applied to derive the system of ordinary differential equations (ODEs) for the beam deflection, cross-section rotation, and in-plane displacement. A numerical solution based on the Taylor series expansion with Cartesian coordinate along the beam is proposed for the system of ODEs. A convergence analysis with respect to the number of terms in the Taylor series expansion is performed. Numerical results for the beam deflection, rotation, in-plane displacement, and induced electric intensity vector are presented for various flexoelectric coefficients and the beam curvature.

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The authors acknowledge the supports by the Slovak Science and Technology Assistance Agency registered under number SK-CN-RD-18-0005, VEGA-2/0061/20.

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Sladek, J., Sladek, V. & Hosseini, S.M. Analysis of a curved Timoshenko nano-beam with flexoelectricity. Acta Mech (2021).

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