Simulation of local scour around a group of bridge pier using flow-3D software

Computational Fluid Dynamics is one of the effective methods to study various hydraulic problems as it saves cost, turnaround time and procures reliable results. It is applied for resolving different fluid flow related problems like flow velocity, density, temperature, and chemical concentrations for any area where flow is present. Today it's a numerical method applied in various industries by combining computational tools and the theory of fluid dynamics in order to achieve flawless product designing. The reduction of local scour downstream of bridge piers got a considerable attention by numerous studies. The purpose of this study was to calculate and quantify the influence of hydraulic structural measures on reducing the scour around a group of bridge piers. In the simulation, the downstream semicircle diameter was fixed by a 10 cm, while the upstream diameter was changed to 4 and 10 cm. Discharges with Q=0.057 m3/s and 0.038 m3/s the piers were tested under clear-water conditions for the duration of 6 hours. Then the results have been compared with laboratory measurements. The agreement between calculated scour depths and laboratory measurements is found reasonable. Keywords: Local scour, scour reduction, bridge pier, group bridge pier.