A Stilling Shaft Connecting a Vertical Shaft and a Retreating Tunnel

Abstract

The invention discloses a stilling well for connecting a vertical shaft with a recession tunnel. The stilling well comprises a stilling well body. The water inlet end of the stilling well body is communicated with the water outlet end of the vertical shaft. The water outlet end of the stilling well body is communicated with the water inlet end of the recession tunnel. A splashing section, a buffering section and an adjusting section which are sequentially connected are arranged in the stilling well body. The water inlet end of the splashing section is communicated with the water outlet end of the vertical shaft. The water outlet end of the adjusting section is communicated with the water inlet end of the recession tunnel. The bottom plate elevation of the water inlet end of the adjusting section is not lower than the bottom plate elevations of the splashing section and the buffering section. The bottom plate elevation of the water outlet end of the adjusting section is higher than the bottom plate elevations of the splashing section and the buffering section. The adjusting section is of a reverse slope structure with the water outlet end higher than the water inlet end. By means of the stilling well, splashed and ejected water bodies can be prevented from hitting the top of the recession tunnel, safety of concrete structures is ensured, the requirement for the discharge capacity of the recession tunnel is met to the maximum extent, and meanwhile the water flow state in the recession tunnel is stable and smooth.

Description

technical field [0001] The invention relates to the field of flood discharge and energy dissipation for shaft spillways in water conservancy and hydropower projects, in particular to a stilling shaft connecting shafts and water retreat tunnels. Background technique [0002] Shaft spillways are used for flood discharge and energy dissipation in water conservancy and hydropower projects, such as figure 1 As shown, its main components are: overflow weir 1, transition section 2, vertical shaft 3, stilling shaft 4, and water retreat tunnel 5. The water retreat tunnel is connected with the stilling well 4. [0003] The water flow in the shaft spillway passes through the overflow weir and forms a high-speed water flow at the lower end of the overflow weir curve; the high-speed water flow breaks away from the shaft wall at the transition section and falls freely in the shaft cavity, shearing and entraining with the air during the falling process The effect, carrying a large amount...

AI Technical Summary

Problems solved by technology

[0005] From the analysis of the movement trajectory of the water flow in the stilling well, since the wall of the cylindrical stilling well has a rigid lateral constraint on the water flow, the inflow and outflow of the water flow occur at the same spatial position, and the momentum direction of the inflow and outflow of the water flow On the contrary, the inflow and the outflow have a head-on collision, and the vertical upward outflow momentum acts on the inflowing water body, resulting in strong splashing and ejection of the water flow

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