Abstract
Recent Development of High Performance Computing has enabled utilization of Computational Fluid Dynamics (CFD) in designs in the engineering field. However, the accuracy of simulated wind forces on a bridge girder using CFD as well as the accuracies of onset velocity and amplitude in fluid-structure interaction problems such as flutter have not yet been investigated well. Furthermore, the calculation time still needs to be improved in order to utilize this CFD in the wind resistant design in a real project. Therefore, in the present study, the accuracy of mean wind force coefficients and flutter derivatives of a box girder using Large Eddy Simulation (LES) is investigated by comparing the results with experimental data from past research. The effects of span-wise domain size on mean and fluctuating wind force and flutter derivatives are also investigated for the purpose of reducing the calculation time by reducing the span-wise domain size in wind resistant design of long-span bridges. Mean wind force coefficients and flutter derivatives could be evaluated by LES with comparable accuracy to a wind tunnel test. It was shown clearly that the effects of span-wise domain size on mean wind force coefficients and flutter derivatives are small while there are relatively large effects on fluctuating wind force coefficients. Therefore, span-wise domain sizes can be reduced for evaluation of mean wind forces and flutter derivatives.
