Abstract:

This paper presents an experimental study and numerical simulations of the flow in an energy dissipator of Y-shape flaring gate pier, stepped spillway, and stilling basin. The flaring gate pier, if with an unreasonable lateral contraction in flood releasing conditions, often produces water splashes that jump over the sidewalls. Three different shapes of sidewall flaring pier were experimentally tested and compared for their overall flow pattern, water wings behind pier, overflow surface pressure, pressure on stilling, and velocity distribution. Results reveal that the flow patterns and energy dissipation in the stilling basin are good when the flaring piers take contraction angles of 19.03° and 17.07°, 19.98° and 13.80°, or 19.98° and 7.0°. And water splashing over the sidewalls can be avoided with the angles of 19.98° and 7.0°.