Numerical Investigation of the Effect of a Pier’s Shape on the Mitigation of Scouring

Nowadays, scouring has become an important issue in coastal engineering. Exposed to a flow, piers of different structures will continually be in danger of scouring. Thus, design of cross-sections for piers in order to produce the least turbulence in the flow passing the pier is a significant concern from hydrodynamical and structural points of view, in so far as the status quo studies concerning optimum pier cross-sections have engaged a major portion of civil engineering researches. In this study, a comparison has been made between the flat-bed scouring pattern in the vicinity of cylindrical and conical piers by investigating the flow pattern around them. Thus, 3D numerical models of flow around a cylindrical pier and conical piers with a same bed diameter as the cylindrical pier and ratios of diameter in the water surface to bed diameters of 0.75, 0.5, 0.375 and 0.25 has been developed, with the models being meshed in GAMBIT and analyzed in FLUENT. The 3D numerical model results of flow pattern around the cylindrical pier were then compared to the experimental data available. These results and data have been used to verify the results of the 3D numerical models of the present study. Consequently, the 3D numerical models of the flow around four conical piers with different slopes have been analyzed and achieved using the FLUENT software, in which specifications of the channel, flow and the software parameters have been set to be same in all models.