Sam Taira
MATHEMATICS COLLOQUIUM
Speaker: Sam Taira Abstract. Fluid flows exhibit rich dynamics over a range of spatial and temporal scales from the their nonlinear interactions. Identification of important interactions present in the flow field can reveal deeper insights into flow physics and may enable interaction-based control of fluid flows. In an effort to understand and characterize the complex web of interactions present in the flow field, we examine the use of network and graph theories on unsteady fluid flows. In the talk, we will discuss three problems to highlight the strength of network analysis. We first consider quantifying the vortical interactions for clusters of potential vortices and derive the sparsified dynamics model. The formulation is then extended to examine turbulent flows, revealing the structures of turbulence networks and their network characteristics. Furthermore, we apply network-based analysis to examine kinetic energy transfer in open cavity flows. From these examples, we demonstrate that the current network-based approaches are able to highlight important nonlinear interactions in the flow field that we not readily captured by traditional analyses. We will also present an overview of the CFD and active flow control efforts undertake by our research group at the beginning of the talk. |