On the role of surface stress tensor in the nonlinear response of time-dependent mechanical actuated nanoplate-type energy piezo-harvesters.

In the present exploration, the role of surface stress tensor as one of the most important size effects at nanoscale in the nonlinear dynamical behavior of nanoplate-type energy piezo-harvesters under a time-dependent mechanical actuation is investigated. The general form of the energy functional associated with a quasi-3D nanosize energy piezo-harvester incorporating the surface Lame constants and the residual surface stress is derived. After that, by taking the Hamilton's principle into consideration, the weak form of the surface continuum mechanics-based governing equations for a nanoplate-type energy piezo-harvester is achieved. Afterwards, the meshless collocation strategy is utilized to numerically solve the established coupled electromechanical surface elastic-based nonlinear problem with the aid of implementing a combined form of the polynomial-kind and radial-kind basis functions to eliminate any singularity which may be observed for the associated moment matrices. One can find that for the nanoplate-type energy piezo-harvesters under simply edge supports owning the thickness of 10 , 20 , and 50 nm , the average value of the achieved voltages are equal to 84.7140 , 169.4280 , and 423.5701 μ v , respectively. However, by taking the role of surface stress tensor into consideration, these values in order reduce to 48.7650 μ v (− 42.44 %) , 126.8687 μv (− 25.12 %) , and 386.3565 μv (− 8.79 %). Moreover, for the nanoplate-type energy piezo-harvesters under clamped edge supports owning the thickness of 10 , 20 , and 50 nm , the conventional average values of the attained voltages are, respectively, 71.9994 , 143.9989 , and 359.9973 μv. However, by taking the role of surface stress tensor into consideration, these values in order decrease to 27.1823 μv (− 62.25 %) , 83.0573 μv (− 42.32 %) , and 328.9342 μv (− 8.63 %) , respectively. Therefore, it is deduced that the role of surface stress tensor in the nonlinear dynamical behavior of nanoplate-type energy piezo-harvesters owing lower thickness is more prominent. [ABSTRACT FROM AUTHOR]