Numerical simulation of flow through side orifice in a circular channel

A side orifice is an important type of hydraulic structure in irrigation and waste management systems to divert desired discharges from a main channel. Circular channel are often used in these systems. In the present study, the flow through a side orifice in a circular channel is numerically simulated. Results show the streamwise and spanwise velocity components in the vicinity of side orifice in different levels. The streamwise velocity decreases along the orifice as one goes from upstream to the downstream. The maximum and minimum value of streamwise velocity component occurs in the upstream end and downstream end of the side orifice, respectively. This decrease is due to the simultaneous increase of the flow depth and decrease of flow discharge in the main channel across the side orifice. Upstream of the side orifice, the spanwise velocity component is low but increases as the flow approaches the downstream edge of the orifice