Performance of Screen in a Sudden Expanding Stilling Basin under the Effect of the Submerged Hydraulic Jump

Abstract

Hydraulic jump is considered the most appropriate option for designers to dissipate energy through stilling basins. Tests on a screen that produced a submerged hydraulic jump were conducted to dissipate the energy of water passing beneath a vertical gate. Various positions of a screen in a sudden expanding stilling basin were investigated. In comparison to the no-screen case, the effect of a screen downstream of the gate on the water surface profile was also investigated. The best screen position was 0.25 of the abutment lengths with a 0.285 relative screen area, which resulted in the most energy loss with the lowest tail water depth and submerged hydraulic jump length. Theoretical equations based on the energy and momentum principles were derived. An acceptable agreement was obtained between the derived theoretical relative depth of the hydraulic jump and the measured values.