A fluid-structure interaction model for numerical simulation of bridge flutter using sectional models with active control devices. Preliminary results

Abstract

A fluid-structure interaction scheme for numerical simulation of actively controlled bridges subject to flutter instability is proposed in this work. In order to suppress or attenuate dynamic instabilities induced by the wind action on long-span bridges, control systems are proposed considering aerodynamic appendices and winglets attached to the deck structure, where control forces are continuously calculated using optimal control theory. The flow fundamental equations are solved here employing the explicit two-step Taylor-Galerkin method and the arbitrary Lagrangian-Eulerian (ALE) description. Eight-node hexahedral finite elements with one-point quadrature and hourglass stabilization are utilized for spatial discretization. Flow turbulence is modeled using Large Eddy Simulation (LES) and a partitioned coupling scheme is adopted for fluid-structure interactions. The structural system is analyzed considering the sectional model approach and a rigid-body formulation for large rotations. Different control techniques and winglet configurations are investigated using prismatic and bridge cross-sections, where control efficiency is evaluated in terms of displacement reduction and energy required by the control system. Preliminary results are obtained here employing approximate flow conditions to verify the control algorithm, where laminar flows and a two-dimensional LES-type approach are utilized.