6th International Conference on Urban Design, Transportation, Architectural and EnvironmentalEngineering (UTAEE-17), İstanbul, Turkey, 8 - 10 September 2017, pp.1-6
Broad crested weirs (BCW) are widely used hydraulic structures in streams and irrigation channels
to control the flow and to measure the discharge due to the advantage of having simple geometry. Interaction of
the turbulent flow with the structure generates vortices and recirculation zone upstream of the weir, which may
cause significant morphological changes on the stream bed. In this study, flow structure upstream of the roundnosed BCW is investigated based on two-dimensional Unsteady Reynolds-Averaged Navier-Stokes Simulations
(URANS). Numerical simulations are conducted using OpenFOAM for different flow rates and rounding
parameters of the weir. The Shear Stress Transport (SST) kthe adverse pressure gradients and separation effects accurately on the channel bottom and weir crest.
Numerical results are reported and interpreted with focus on the effect of rounding on the length of the