Investigation of Active Hybrid Composites for Thermal Energy Harvesting

Abstract

The present work proposes a predominantly analytical treatment of the behavior of several types of monolithic and composite SMA structures. In particular, the behavior of superelastic SMA prismatic beams, circular shafts and springs is addressed considering a complete loading-unloading cycle. The obtained results are then utilized in deriving governing equations for several composites with embedded SMA elements, including elastic beams with reinforced with one or more SMA wires and thin plates, bi- and multi-layer FGM-SMA laminates, and a SMA-piezoelectric device. This last type of SMA-enabled structure can be used for harvesting energy through structure-wide thermo-electro-mechanical coupling, whereby the deformation of the SMA element is exploited in deforming the piezoelectric constituent, thereby generating an electric charge. Such energy harvesting technology can be powered by mechanical or thermal stimuli of various frequencies and amplitudes, making it interesting from both academic and practical perspectives. Because of limitation in the time allocated to completing the present doctoral research, only the response of the SMA-piezo composite to mechanical loading is considered. The response to thermal loading can be addressed using the same combination of constitutive and deformation theories but would require varying the temperature, either directly as a parameter, or by solving the heat equation. The relevant derivations will be carried out in subsequent work.

Date of Award	Jun 2019
Original language	American English