Simulation of the Flow Past of Bridge Box Girders in Turbulent Flow by LargeEddy Simulation

摘要

Large-eddy simulation(LES) technique for turbulence flow has been used for predicting theflow past of box girder sections of bridges, in which the large-eddy model with dynamic SGSmodel is usually employed. A stochastic method has been adopted to generate homogeneousturbulence with specified power and cross spectra in the oncoming flow. Then in the smooth flowand several turbulent flows, the flow field of one typical box girder is simulated. The results revealthat turbulent flow field has obvious influences on the flow field and aerodynamic parameters of thecross section. The turbulence can influence the generation of the wake vortex, and with the increasein turbulent intensity, the mean drag coefficients decrease, which is caused by the decrease in meanpressure coefficients in the wake surface mainly. This feature is as same as the Reynolds numbereffects of the box gird in wind tunnel testings. Therefore, the Reynolds number effects of boxgirders can be relieved effectively by adding the turbulence in CFD simulation.