Multi-layer network analysis of fluid-structure interactions

The coupling interactions between deformable structures and unsteady fluid flows occur across a wide range of spatial and temporal scales in many engineering applications. These interactions make it challenging to predict the flow physics and structural loads accurately. We propose two multi-layer network approaches to characterize the interactions between the fluid and structural layers in a 2D laminar flow over a flat plate at 50 degrees angle of attack. In one approach, the grid vortices and bound vortexlets form the nodes of the network with the edges defined by induced velocity. In the other approach, coherent structures (fluid modes) contributing to kinetic energy and structural modes contributing to strain energy constitute the network nodes. The energy transfers between the modes are extracted using a perturbation approach. The interactions are further simplified using network community detection. The present work aims to create a network-theoretic framework for reduced-order modeling of multiphysics systems.