Numerical Investigation for Aerodynamic Derivatives of Bridge DeckUsing DES

摘要

Detached Eddy Simulation（DES）is quite a new approach for the treatment of turbulence, which unites theefficiency of Reynolds Averaged Navier-Stokes Simulation (RANS) and the accuracy of Large Eddy Simulation (LES)into one framework. In this paper, DES method based on Spalart-Allmaras (S-A) turbulence model is employed tosimulate the incompressible viscous flow around bridge decks. In order to obtain the aerodynamic forces, the forcedmotion simulations of the bridge decks are implemented by self-developed codes combined with FLUENT software. Afterobtaining the aerodynamic forces, aerodynamic derivatives are determined based on the least square algorithm. As theexamples, the thin flat plate and the Great Belt East Bridge suspended spans cross-section are investigated to calculatetheir aerodynamic derivatives. Finally, the simulation results are compared to the data reported in other studies. Thecomparisons show that the present method gives much better prediction of the aerodynamic derivatives than RANSmethod and discrete vortex method (DVM).