Rectification energy dissipation method for inverse step stilling basin and stilling basin

Abstract

The invention discloses a rectification energy dissipation method for an inverse step stilling basin and the stilling basin. A conventional end sill shape is replaced with a continuous inverse step end sill at the tail end, so that water flow collides with the end sill in a layering manner, the phenomenon of surge caused by straight wall type or steep slope type end sill collision and more concentrated water flow impact force in the basin are avoided, the flow regime of collision, mixing and turbulence of the water flow which is not discharged from the basin can be enhanced, and by collision energy dissipation and increasing of conjugate water depth of water jump, the length of the basin can be effectively decreased, energy dissipation rate can be increased, and energy dissipation and speed regulation functions can be realized. The rectification energy dissipation method and the stilling basin are applied to the conditions of high and medium water heads, high Fr coefficient, connection of the stilling basin to the downstream, uniform inflow and outflow and coaxiality between the axis of a river channel after an outlet and the water flow discharged from the basin.

Description

technical field [0001] The invention belongs to the field of flood discharge and energy dissipation of water conservancy and hydropower projects, and relates to an energy dissipation method and a stilling pool. Background technique [0002] In water conservancy and hydropower discharge structures, when the discharge is connected with the downstream natural river, it is necessary to dissipate energy and adjust the flow velocity distribution. High water head and high Fr number (Fr number is called Froude number, which is a hydraulic parameter, hereinafter referred to as "Fr number") discharge conditions, can be used to add water cushion ponds, or bottom flow and surface flow can be used to add stilling force Pond and other measures to achieve the purpose of energy dissipation and anti-scour. When using bottom flow energy dissipation, stilling pools are often used to form hydraulic jump energy dissipation flow patterns, and the shape of the tail sill of the stilling ponds has ...

AI Technical Summary

Problems solved by technology

Bottom flow energy dissipation is often used to form a hydraulic energy dissipation flow state in a stilling pool, and the shape of the tail sill of the stilling pool has a great influence on the flow state in the pool

At the present stage, the facing surface of the tail sill mostly adopts the straight wall type or the type with a steep slope. When the combination of upstream and downstream water levels is unfavorable, there may be surge flow due to the collision of the tail sill, and the tail sill is strongly impacted by the water flow, and the tail sill The top water flow is tumbling violently, often poorly connected with the downstream water level, resulting in unfavorable water flow patterns

[0003] The step energy dissipation method has been applied in the fields of water conservancy engineering, landscape design, river sand control and fishway engineering. In water conservancy projects, steps are often used to dissipate energy on the dam surface and spillway. , collision, to achieve the purpose of energy dissipation and aeration, and most of them are positive steps (that is, the plane elevation of each step decreases step by step along the direction of water flow), and for reverse steps (that is, the plane elevation of each step increases step by step along the direction of water flow) The energy dissipation method currently adopts a step type (such as ridge, pier, etc.) to rectify or generate a forced hydraulic jump, but the energy dissipation effect needs to be improved

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