Shape Optimization for Energy Harvesting Applications

The goal of this research is to optimize the shape of a structure for maximizing the energy harvested through mechanical vibrations of a smart structure. The work will be focused on optimizing the shape of both, the smart material and the substructure on which it is attached. The multidisciplinary aspect of this work arises due to the interaction between structural modes of the vibrating system, properties of the smart material and electrical parameters that affects the energy generation. A change in the shape of the smart material primarily changes the vibration modes of the system that directly affects the amount of energy harvested. The objectives of this work are (a) create a numerical model for energy harvesting using microfiber composite (MFC) patches attached to aluminum beam, (b) validate the model by performing experiments, (c) perform modal analysis of the system, (d) perform shape sensitivity analysis using accurate and efficient methods, and (e) optimize the system using a gradient-based optimizer. Results obtained from model validation indicate that errors in the experimentally measured damping of the first mode significantly affect the voltage obtained from the numerical model. Consequently, this might also affect the optimization results. The shape optimization problem has a nonlinear constraint that is explained in detail and challenges involved in performing sensitivity analysis calculations are highlighted.