Numerical investigation for flutter instability of bridge using FSI model within the lattice Boltzmann framework

In order to simulate wind-bridge interaction and study bridge flutter instability effectively, a lattice Boltzmann analysis of fluid-structure interaction (FSI) problems was presented. The flow around a rigid fixed bridge cross-section was modeled by large eddy simulation (LES) through incorporation of dynamic sub-grid-scale (SGS) model in multiple relaxation time lattice Boltzmann method(MRT-LBM). The time discretization of the structural dynamics was performed using Runge-Kutta method. The loosely-coupled partitioned algorithm was accomplished by updating fluid-structure interfaces via moving boundary technique of lattice Boltzmann method. In the end, the Great Belt East Bridge was investigated to study its flutter instability using self-developed codes. A good agreement was found between the simulation and the existing results regarding the critical flutter speed of Great Belt East Bridge. Moreover, the study showed that the present methodology has a well prediction for the onset of flutter instability.