Three-dimensional numerical modeling of score hole in rectangular side weir with finite volume method

Local scouring in the downstream of hydraulic structures is one of the important issues in river and hydraulic engineering, which involves a lot of costs every year, so the prediction of the rate of scour is important in hydraulic design. Side weirs are the most important of hydraulic structures that are used in passing flow. This study investigate the scouring due to falling jet from side weir in downstream in side channel numerically. The simulation was done with finite volume method. The comparison of numerical and experimental results of flow fields shows agreement. Results show that from upstream to downstream of side weir located in side channel, scoring is increased and the dimensions of the scour hole in the downstream of the rectangular side weirs increase along it. In fact, at the downstream of the lower edge of side weirs in side channel, scouring has the greatest dimensions; in particular the depth.