Numerical and Experimental Modeling of Flow Over a Broad-Crested Weir

Abstract

Broad-crested weirs are hydraulic structures installed in open-channels used to control the flow of water and measure the discharge. In this study, the flow over a broad-crested weir in open-channel was experimentally and numerically modeled. Experiments were carried out in a channel with a length of 1.5 m and a width of 0.055 m under five different flow rates. In each experiment, water depth and flow velocity in flow direction were measured using a pitot tube. Numerical model was developed using SimFlow software. The velocities and pressure fields were computed numerically. The water depths and velocities in flow direction obtained from the numerical model were compared to experimental values. There is generally a good agreement between experimental and numerical results. Relatively small errors in velocity profiles are observed in higher discharges.

Keywords

• broad-crested weir,computational fluid dynamics,SimFlow

References

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