Numerical Simulation of Flow Pattern around the Bridge Pier with Submerged Vanes

Abstract

Bridges are very important for establishing communication paths. For this reason, it is important to control scour around bridge piers. Several methods have been proposed for scour control. One of the most useful methods is the use of submerged vanes. In the other hand, laboratory circumstances force many considered effective factors to be skipped in the scour phenomenon. In this situation, the importance of using numerical models would appear even more. In this research, numerical simulation of the flow pattern around the piers surrounded by submerged vanes has been carried out. For this purpose, the structure simulated in three dimensions using Fluent software. K-e turbulence model with VOF and mixture models for multiphase flow simulation were applied. Afterward analysis of the water surface profiles, velocity distribution profiles, and shear tension of the bed in multiple placements conditions including multiple vanes within two flow intensity and two different angles were performed. The results showed that there is a good agreement between numerical and experimental results. The best models in this research were found to be Realizable k-e turbulence model with VOF multiphase model for water surface profile and velocity distribution profiles. The maximum extracted relative errors for water surface profiles and velocity distribution profiles were 2.23% and 2.92%, respectively. Also, analysis of the counts and placement angles showed that 6 vanes rather to 2 and 4 vanes and also angle of 30 degrees rather to angle of 20 degree performs better in action. The other results of this study, are no change in water surface profiles, reduction of the velocity and the amount of shear stress around the piers in different placement conditions including multiple submerged vanes.