140 / 2024-02-19 17:30:43

Investigation of auxiliary energy dissipator on submerged hydraulic jump with deep tail water stilling basin

deep tail water; physical model；hydraulic jump; auxiliary energy dissipator

Due to the deep tail water inside the stilling basin, the traditional submerged hydraulic jump is commonly subjected to insufficient energy dissipation and excessive outgoing flow velocity, thus seriously scouring the downstream river bed. Based on a physical model, this paper respectively arranges various auxiliary energy dissipators (baffle blocks, T-shaped piers and chute sill blocks) to investigate each energy dissipation difference. The physical results show that both the baffle blocks and the T-shaped piers can hardly touch the mainstream or improve the flow pattern inside the deep tail water stilling basin in view of the limited geometrical dimension, which presents little influence upon the submerged hydraulic jump. But the chute sill blocks above the spillway surface can effectively shrink the bottom overflow section and offset the upper rushing overflow, thus greatly arousing local turbulence and diffusion among the rushing inflow at the inlet of stilling basin. Those local adjustment could greatly improve the rushing inflow to shorten submerged hydraulic jump length and increase energy dissipation effect, which correspondingly decreases down the outgoing flow velocity with secondary hydraulic jump disappearing. These investigations could provide important reference for similar deep tail water projects.