Nonlocal couple stress-based meshless collocation model for nonlinear dynamic performance of microbeam-type piezoelectric energy harvesters

The prime aim of the current exploration is that to analyze the size-dependent nonlinear dynamics of microsize laminated bridge-type piezoelectric energy harvesters containing a passive core made of an agglomerated nanocomposite and piezoelectric surface layers under a time-dependent mechanical load. For this purpose, the both nonlocal and couple stress tensors are incorporated to the classical quasi-3D shear flexible beam theory to model microsize beam-type laminated energy harvesters. After that, a numerical solution methodology based on the meshless collocation method is employed to discretize the obtained size-dependent nonlinear equations via using a coalesce basis function including polynomial and multiquadric parts on the basis of the Chebyshev node distribution scheme to remove any possible singularity. The nonlinear time histories relevant to the induced lateral deflection and extracted voltage are plotted in the presence and absence of the nonlocal and couple stress tensors as well as various values of the agglomeration constants relevant to the nanocomposite passive core of microsize energy harvesters. One can find that by increasing the cluster volume fraction, the effect of the nonlocal stress tensor on the extracted voltage from the microsize energy harvester increases from +16.50% to +17.53% in the case of simply supported end conditions, and from +21.84% to +22.99% in the case of clamped end conditions. In addition, the effect of the couple stress tensor enhances from -22.21% to -23.09% in the case of simply supported end conditions, and from -27.15% to -27.94% in the case of clamped end conditions.