Specific Energy and Energy Density Analysis of Conventional and NonConventional Flywheels

Abstract

Flywheels are widely used as a means of energy storage throughout different applications such as hybrid electric vehicles, spacecraft, and electrical grids. The research presented here investigates various steel flywheel constructions. The purpose of this research was to increase the energy density of a flywheel by reducing the centrifugal stresses that occur during operation. Various configurations were attempted, with some consisting of metal, composite, or both. This thesis documents the steps taken in determining and analyzing the proposed designs. Increase of the energy storage in metal flywheels is accomplished most efficiently through optimization of the flywheel geometry. Energy storage of the hybrid and composite flywheels shows large room for improvement.

Modeling and simulation of the various systems were conducted with the Finite Element Analysis (FEA) software ANSYS Classic v 13.0. A combination of input files and the GUI was used for the analysis. The results are verified with analytical solutions where applicable. Novel flywheel designs are converged to ensure accurate results.