A kind of groove of letting out
The present invention relates to the Hydraulic and Hydro-Power Engineering outlet structure escape works and let out groove, particularly a kind of ladder that becomes the high roughness of the gradient is let out groove.
For the Hydraulic and Hydro-Power Engineering outlet structure escape works, letting out groove is the passage of confinement of flow, guiding current.At present, base plate, the side wall of letting out groove adopt smooth continuous smooth-going pattern more, ideally, the smooth-going groove of letting out has preferably adaptive capacity to high-velocity flow under the cooperation of air mixing corrosion reducing facility, can guide preferably under the current and let out, and reduce or remit self cavitation erosion and erosion attack, but in the reality, because flow velocity is high, the smooth-going groove of letting out still has and is subject to cavitation erosion and erosion attack example.In the situation less at the flow rate of water flow of letting out groove, that discharge per unit width is little, let out groove and can adopt the ladder pattern, ladder is let out groove can be along the journey energy of current stopped that disappears under the effect of ladder, reduce the lower stream flow velocity that sluices, be conducive to the linking of downstream river course current, ladder is let out groove easily by the high-velocity flow erosion attack, lets out the groove flow rate of water flow and need to control within the specific limits.
Summary of the invention
Technical problem to be solved by this invention is, and is not enough for prior art, and a kind of groove of letting out is provided, and reduces the risk of letting out groove self cavitation erosion and erosion attack, reduces the anti-stamping press of the energy dissipating of letting out the groove downstream, improves the flood discharge safety.
For solving the problems of the technologies described above, the technical solution adopted in the present invention is: a kind of groove of letting out, the side wall that comprises base plate and base plate both sides, described base plate comprises some sections step boards and some sections smooth-going base plates, step board and smooth-going base plate interval layout, described smooth-going base plate and/or side wall are provided with several prominent bodies.
As preferred version, described prominent body interlaced arrangement.
Described prominent body is hemispherical or streamlined, and the height of prominent body is 0.5m～2.0m.
The described step board gradient is 5～60
As preferred version, also comprise the air mixing corrosion reducing facility, described air mixing corrosion reducing facility is connected with the base plate upstream extremity.
Compared with prior art, the beneficial effect that the present invention has is: the present invention is by arranging prominent body at chute bottom slab and/or side wall, improve the roughness of letting out groove, increase frictional resistance, improved disorderly kinetic energy dissipation rate, a large amount of flow energy that dissipates has reduced the risk of letting out groove self cavitation erosion and erosion attack, reduce the anti-stamping press of the energy dissipating of letting out the groove downstream, improved the flood discharge safety.
Description of drawings
Fig. 1 is one embodiment of the invention front view;
Fig. 2 is one embodiment of the invention longitudinal sectional view;
Fig. 3 is one embodiment of the invention transverse sectional view.
The specific embodiment
As shown in Figure 1-Figure 3, one embodiment of the invention comprises the side wall 3 of base plate 2 and base plate both sides, described base plate 2 comprises some sections step boards 5 and some sections smooth-going base plates 6, step board 5 and smooth-going base plate 6 intervals layout, and smooth-going base plate 6 and/or side wall 3 are provided with several prominent bodies 1; Prominent body 1 is hemispherical or streamlined, and the height of prominent body 1 is 0.5m～2.0m, prominent body 1 interlaced arrangement; Step board 5 gradients are 5～60
0Air mixing corrosion reducing facility 4 is connected with base plate 2 upstream extremities.
The size of prominent body 1 should be definite according to letting out the groove hydraulics, and when adopting the prominent body of hemispherical, the ratio of hemispherical height and end circular diameter can be controlled between 1:2～1:8; Vertical or horizontal spacing between the prominent body 1 can be controlled at the bottom of 2～8 times of hemisphericals between the circular diameter, and to obtain maximum roughness value, the roughness value can be controlled between 0.04～0.12; Prominent body can adopt prefabricated units, and the reserved steel bar joint, during construction it is lifted to the installation site, and reserved steel bar is connected with peripheral reinforcing bar, and then the groove concrete is let out in cast.
At chute bottom slab and side wall prominent body is set, can improve the roughness of letting out groove, increase frictional resistance, current are under the effect of prominent body, flow to sharply change, prominent body downstream forms the shearing energy dissipating whirlpool body of various yardsticks, and the inner turbulence intensity of water body obviously increases, improved disorderly kinetic energy dissipation rate, a large amount of flow energy dissipates.Current form at step board and shear energy dissipating whirlpool body, can increase substantially along the journey energy dissipation rate, because base plate is fold-line-shaped, and current are attached on the chute bottom slab, the water surface rises and falls simultaneously, and current gradient increases, and operation length increases, and the more flow energy of stopping disappears.