MCE Ph.D. Thesis Seminar

Fluid-structure interaction (FSI) is ubiquitous in the natural and engineered world, and better understanding of FSI systems can aid the design of renewable energy harvesting technologies, bio-inspired propulsion vehicles, and biomedical devices. Towards this end, we discuss the development and application of numerical methods for performing high fidelity simulations and analysis of FSI systems. Among the methods discussed are an immersed-boundary method for performing efficient simulations of the fully-coupled nonlinear equations, a global stability solver for educing instability-driving mechanisms within the system, and a data-driven decomposition approach that takes account of both the fluid and the immersed structure. We then apply these techniques to elucidate the physics of an inverted flag in a uniform flow, in which the flag is clamped at its trailing edge. We identify the physical mechanism responsible for the onset of flapping, investigate the role of vortex shedding in large-amplitude flapping, and characterize the chaotic flapping regime that the system undergoes for a range of parameters.