Flip bucket

Abstract

The invention provides a flip bucket which is connected with a spillway, a bottom plate of an outlet section of the spillway is connected with an inclined bottom slope descending along the way, the width of the inclined bottom slope is increased along the way in the downstream direction to form an overshot flip bucket, and the overshot flip bucket is flush with the tail end of a side wall of the spillway; an outlet of the downward shooting flip bucket is closely connected with the tooth bank set, the tooth bank set comprises N tooth banks arranged at intervals, and the outlet of the downward shooting flip bucket is divided into N + 1 downward jet flow areas and N flip flow areas. According to the flip bucket, a tooth bank set composed of a plurality of tooth banks arranged at intervals is arranged at the tail end of a spillway, the width of the tooth bank is increased in the downstream direction along the way, water flow transversely diffused in a discharge chute along the way forms a spatial multi-dimensional nappe, the unit width flow at the outlet of the spillway is reduced, and the downstream scouring depth and the hydraulic index are low; and the protection work amount and the construction cost are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of diverting flow and energy dissipation in water conservancy projects, and in particular relates to a diverting flow nose sill. Background Art

[0002] Energy dissipation by diverting flow refers to setting up different forms of diverting flow noses at the end of the discharge structure to divert the high-speed water flow from the upstream to the downstream, and dissipate part of the energy through the diffusion, turbulence and aeration of the jet in the air, and then fall into the river far away from the building to dissipate energy in a water cushion of a certain depth and range. Due to the advantages of simple structure, economy and easy maintenance, diverting flow energy dissipation is often used in water conservancy and hydropower projects when the downstream geological conditions are good and the wave requirements are not high.

[0003] Among the various types of sills commonly used at present, the conventional continuous sill has a large inlet single-width flow rate, deep downstream scouring and high hydraulic indicators; the differential sill adds convex bodies at intervals on the basis of the conventional continuous sill, which can effectively disperse the inlet width of a single chute outlet water tongue, reduce the inlet single-width flow rate, and reduce the downstream scouring depth, but the convex bodies are set on the continuous sill, and the risk of cavitation and erosion on both sides of the convex bodies is high; the narrow slit sill stretches the outlet water flow longitudinally, which can reduce the scouring effect of flood discharge on the slope, but the scouring downstream is generally deeper; the bevel sill can effectively diffuse the outlet water flow and reduce the inlet single-width flow rate, and is mainly suitable for riverbank spillways; the tongue-shaped sill can diffuse the outlet water flow in the horizontal direction and reduce the inlet single-width flow rate, and is mainly suitable for wider downstream rivers. After the facility discharges water, there is a lot of water accumulation in the anti-arc section of the sill, which is not conducive to maintenance. At the same time, all the above-mentioned types of flow noses have atomization problems to varying degrees, which is not conducive to the stability of the slopes around the flood discharge and energy dissipation area and the protection of facilities and equipment. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a flow nose sill with a simple structure, which has the advantages of small single-width water inlet flow, low cavitation and erosion risk, shallow downstream river channel scour and small atomization.

[0005] The invention discloses a nose sill connected to a spillway, wherein the bottom plate of the outlet section of the spillway is connected to a sloped bottom slope that descends along the way, and the width of the sloped bottom slope increases along the way toward the downstream direction to form a nose sill, and the nose sill is flush with the end of the side wall of the spillway; The outlet of the dive ridge is adjacent to the tooth ridge group, and the tooth ridge group includes N tooth ridges arranged at intervals, dividing the outlet of the dive ridge into N+1 dive flow areas and N diversion flow areas; The structural parameters of any of the tooth ridges include the width, length and pick angle of the starting end, wherein: The starting width of any of the tooth sills is selected from one of B2 and B4, the value range of B2 is [0.6h, h], the value range of B4 is [0.8h, 1.5h], and h is the water depth at the end of the spillway sill under the maximum discharge condition; The length of any of the teeth is selected from L1 and L2. , , where: q is the single-width flow rate at the end of the spillway sill (3) under the maximum discharge condition; The pick angle of any of the tooth ridges is selected from one of θ1 and θ2, , , where: The value range of is [4°, 8°], and v is the flow velocity at the end of the spillway sill (3) under the maximum discharge flow condition.

[0006] The end of the spillway is set as a diving sill, and the width of the sill section increases along the downstream direction, so that the water flow is laterally diffused along the way in the chute, reducing the single-width flow at the spillway outlet. A tooth sill group composed of multiple spaced tooth sills is set at the diving sill outlet to divide the sill outlet into multiple diving flow areas and multiple diversion flow areas, so that the water flow after exiting the sill forms a spatial multi-dimensional water tongue that is fully diffused laterally and vertically, further reducing the single-width flow at the spillway outlet. At the same time, the structural parameters of each tooth sill can be set differently to form diving flow areas and diversion flow areas of different sizes, different single-width flows and controllable landing positions to match different downstream boundary conditions.

[0007] Furthermore, a side aeration sill is provided on the inner wall of the side wall where the downward-projecting sill meets the spillway. The side aeration sill is of a sudden expansion type, and the sudden expansion width b1 ranges from [0.20m, 0.40m].

[0008] A sudden expansion side aeration sill is set on the inner wall of the side wall at the starting section of the downward-projecting sill to avoid cavitation damage to the diffusion side wall caused by high-speed water flow.

[0009] Furthermore, the range of the angle θ of the downward-facing ridge is [-10°, -30°], which shortens the water tongue ridge distance and suppresses atomization caused by flood discharge.

[0010] Furthermore, the difference Δh between the terminal elevation of the downward-jumping embankment and the highest water level downstream is less than 10 m, so that the water flow in the downward-jumping flow area after leaving the embankment directly enters the downstream river channel to collide and shear with the water body to dissipate energy.

[0011] Furthermore, the diffusion angle α1 of the left wall of the overlooking ledge has a value range of [1°, 7°].

[0012] Furthermore, the diffusion angle α2 of the right wall of the downward-facing overhanging ridge has a value range of [1°, 7°].

[0013] According to the determined landing point position, the diffusion angles of the left and right walls of the prone sill are flexibly adjusted to adjust the diffusion direction of the sill, so as to ensure that the water falls at the designed landing point after flowing out of the sill to avoid impacting the downstream slope.

[0014] Furthermore, the contraction angle β of the tooth ridge has a value range of [0°, 10°]. The tooth ridge can be a rectangular tooth ridge of equal width or a trapezoidal tooth ridge that gradually contracts along the direction of the water flow according to different flow selection area parameters.

[0015] Furthermore, the teeth in the tooth group are arranged in an alternating pattern with regular sizes; the protruding teeth ensure smooth air supply on both sides of the teeth to avoid cavitation. At the same time, the separated adjacent diversion areas allow the water flow to diffuse and stretch in the air before entering the downstream, significantly improving the energy dissipation efficiency; or, the teeth in the tooth group are arranged in a pattern with a number of large teeth in the middle and a number of small teeth symmetrically arranged on both sides; the middle large tooth stretches the water tongue range longitudinally, concentrates the mainstream to the distant deep water area, and fully utilizes the water cushion to dissipate braking energy; the middle large tooth guides the water flow to fall away from the structural foundation, reducing the impact on the proximal riverbed; the small teeth on both sides assist in dispersing the water flow, promote the full longitudinal and lateral diffusion of the water tongue, improve the overall energy dissipation effect, weaken the concentrated scouring force of the opposite slope, and reduce the depth of the scouring pit.

[0016] Furthermore, the height difference △Z between the tooth sill group and the bottom plate of the downstream river channel is greater than 20.0m, and the height difference is increased to extend the range, making it easier to dissipate energy in deep water areas.

[0017] The present invention has the following beneficial effects: 1) The nose sill provided by the present invention adopts a diffusion-type plunging sill design at the end of the spillway, so that the water tongue in the chute can diffuse significantly in the lateral direction. A plurality of tooth sills arranged at intervals are arranged after the plunging diffusion sill, so that the water tongue can fully diffuse in the longitudinal and lateral directions after leaving the sill, forming a multi-dimensional space water tongue. The single-width flow is greatly reduced compared with the traditional continuous sill, the downstream scouring depth and hydraulic index are low, and the amount of protective engineering and construction costs are reduced; 2) The nose sill provided by the present invention is provided with multiple tooth sills for adjusting the water tongue landing point on the downstream side of the downward-facing sill, which has a simple structure, smooth water flow transition, no cavitation risk, and no operation restrictions; 3) The water tongue of the nose ridge provided by the present invention has a short flying distance, and the water tongue has small air expansion in the air, which avoids the strong atomization caused by the high-speed water flow entering the downstream, and ensures the stability of the downstream slope and the safe operation of nearby buildings, roads and equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the planar structural arrangement of the nose ridge provided by some embodiments of the present invention, Figure 2is a schematic diagram of the planar structural parameters of the nose ridge provided by some embodiments of the present invention, Figure 3 is a schematic diagram of the cross-sectional structure of the nose ridge provided by some embodiments of the present invention, Figure 4 6-1 is a schematic cross-sectional view of a tooth ridge corresponding to a flow-diverting area of ​​a flow-diverting nose ridge 6-1 provided in an embodiment of the present invention. Figure 5 6-2 is a schematic cross-sectional view of a tooth ridge corresponding to a flow-diverting area of ​​a flow-diverting nose ridge 6-2 provided in an embodiment of the present invention. Figure 6 It is a schematic cross-sectional diagram of the tooth ridge corresponding to the flow-diverting area of ​​the flow-diverting nose ridge 6-3 provided in an embodiment of the present invention.

[0019] Description of reference numerals: 1 the outlet section of the spillway, 2 the side wall of the spillway, 3 the protruding sill, 4 the side aeration sill, 5-1 the protruding jet flow area, 5-2 the protruding jet flow area, 5-3 the protruding jet flow area, 5-4 the protruding jet flow area, 6-1 the protruding flow area, 6-2 the protruding flow area, 6-3 the protruding flow area, 7 the guardrail, 8 the downstream river channel, 9 the protruding flow tongue drop area; Parameter identifier: The width of the spillway in front of the sill is b, the height of the side aeration sill is b1, the diffusion angle of the left wall of the sill is α1, the diffusion angle of the right wall of the sill is α2, the height of the side wall of the sill is H, the angle of the sill is θ, the width of the outlet of the sill is B, The outlet width of the jet zone 5-1 is B1, the outlet width of the jet zone 5-2 is B3, the outlet width of the jet zone 5-3 is B5, and the outlet width of the jet zone 5-4 is B7; The starting width of the tooth ridge corresponding to the flow zone 6-1 is B2, the length is L1; the angle of the flow zone 6-1 is θ1, the contraction angle is β1, the arc radius is R1, The starting width of the tooth ridge corresponding to the flow zone 6-2 is B4, the length is L2; ​​the angle of the flow zone 6-2 is θ2, the contraction angle is β2, the arc radius is R2, The starting width of the tooth ridge corresponding to the flow picking area 6-3 is B6, the length is L3; the picking angle is θ3, the contraction angle is β3, and the arc radius is R3; The difference between the elevation of the end of the downward-projecting overhang and the highest water level downstream Δh, the difference between the elevation of the end of the negative overhang and the elevation of the downstream riverbed ΔZ, and the length of the guardrail L. DETAILED DESCRIPTION

[0020] In order to more clearly and completely describe the technical solution of the present invention, the present invention is further described in detail through specific embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention. Various changes can be made within the scope of the rights of the present invention.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0022] The present invention provides a nose sill connected to the spillway, the bottom plate of the outlet section 1 of the spillway is connected to the inclined bottom slope that descends along the way, the width of the inclined bottom slope increases along the way in the downstream direction to form a sloping sill 3, so that the water flow is diffused laterally along the way in the chute, and the single-width flow at the outlet of the spillway is reduced. The sloping angle θ of the sloping sill 3 is in the range of [-10°, -30°], and the sloping sill 3 is flush with the end of the side wall 2 of the spillway; the diffusion angles of the left and right walls of the sloping sill 3 are α1 and α2, respectively, and the range of values ​​is [1°, 7°]. In order to prevent the diffusion side wall from being damaged by cavitation due to the high-speed water flow, a side aeration sill 4 is set on the inner wall of the starting end side wall where the sloping sill 3 is connected to the spillway, and the side aeration sill 4 is in the form of a sudden expansion, and the sudden expansion width b1 is in the range of [0.20m, 0.40m].

[0023] The outlet of the protruding ridge 3 is adjacent to the tooth ridge group, the outlet width of the protruding ridge 3 is B, and the tooth ridge group includes N tooth ridges arranged at intervals, which divide the outlet of the protruding ridge 3 into N+1 protruding flow areas and N protruding flow areas. In one embodiment provided by the present invention, Figure 1 and Figure 2 As shown, the tooth ridge group includes three tooth ridges. The middle tooth ridge is a slightly larger isosceles trapezoid, and slightly smaller isosceles trapezoids are symmetrically distributed on both sides. The three tooth ridges divide the outlet of the dive ridge into four dive flow areas 5-1, 5-2, 5-3 and 5-4 and three diversion flow areas 6-1, 6-2 and 6-3.

[0024] The corresponding widths of the four jet flow zones 5-1, 5-2, 5-3 and 5-4 are B1, B3, B5 and B7, respectively, where B1=B7, and the value range of B1 and B7 is [0.4h, 0.8h]; B3=B5, and the value range of B3 and B5 is [0.6h, h]; h is the water depth at the end of the jet sill of the spillway under the maximum discharge flow condition.

[0025] The water flow in the downward jet zone falls near the sill, making full use of the water body at the front end of the downstream water energy dissipation zone for energy dissipation, thus improving the energy dissipation effect. At the same time, due to the downward jet type, the lateral diffusion of the water flow in the B1 and B7 jet zones is controllable, and the front and rear positions of the water tongues are also fixed under various operating conditions, which is beneficial to the protection of the downstream slope.

[0026] The width, length and angle of the tooth sills forming the diversion areas 6-1, 6-2 and 6-3 can be the same, or can be set according to the difference in downstream boundary conditions; the value range of the contraction angle β of the tooth sill is [0°, 10°], and the planes of the tooth sills of the three diversion areas can be selected as rectangles (the value of β is 0°) or trapezoids (the value range of β is (0°, 10°]), so as to achieve effective diffusion of the water tongues in each diversion area in the longitudinal and transverse directions, reduce the single-width flow when entering the water, and improve the energy dissipation rate and the stability of the downstream water surface.

[0027] The width, length and angle of the tooth ridge corresponding to the diversion area 6-2 are larger than those of the tooth ridges corresponding to the diversion areas 6-1 and 6-3.

[0028] a) The structural parameters of the tooth ridge corresponding to the flow zone 6-1 are designed according to the following requirements: The starting width B2 of the tooth sill corresponding to the diversion area 6-1, the value range of B2 is [0.6h, h], h is the water depth of the end of the diversion sill of the spillway under the maximum discharge condition; The length L1 of the tooth ridge corresponding to the flow zone 6-1 is: , Where: q is the single width flow at the end of the spillway sill under the maximum discharge condition; The value range of the contraction angle β1 of the tooth ridge corresponding to the flow selection area 6-1 is [5°, 10°]; The angle θ1 of the tooth ridge corresponding to the flow zone 6-1 is increased based on the depression angle θ of the depression ridge. , The value range is [4°, 8°].

[0029] b) The structural parameters of the tooth ridge corresponding to the flow zone 6-2 are designed according to the following requirements: The width B4 of the starting end of the tooth sill corresponding to the flow area 6-2, the value range of B4 is [0.8h, 1.5h], h is the water depth of the end of the spillway sill under the maximum discharge condition; The length L2 of the tooth ridge corresponding to the flow zone 6-2 is: , Where: q is the single width flow at the end of the spillway sill under the maximum discharge condition; The value range of the contraction angle β2 of the tooth ridge corresponding to the flow selection area 6-2 is [5°, 10°]; The pick angle θ2 of the tooth ridge corresponding to the pick flow area 6-2 is: , Where: θ is the depression angle of the downspout sill 3; q is the single-width flow at the end of the downspout sill 3 of the spillway under the maximum downspout flow condition; v is the flow velocity at the end of the downspout sill 3 of the spillway under the maximum downspout flow condition.

[0030] c) The structural parameters of the tooth ridge corresponding to the diverter zone 6-3 refer to the design of the tooth ridge corresponding to the diverter zone 6-1. The width of the tooth ridge corresponding to the diverter zone 6-3 at the starting end is B6=B2, and the length is L3=L1; the diverter angle θ3=θ1, the contraction angle β3=β1, and the arc radius R3=R1.

[0031] The height difference △Z between the negative sill of the sill and the bottom plate of the downstream river channel 8 should be greater than 20.0m to extend the range and facilitate the use of deep water area for energy dissipation.

[0032] Example

[0033] In order to control the impact of atomization and reduce the impact of flood discharge atomization on downstream slopes and facilities and equipment, a project uses a diffused cantilevered combined cantilevered nose sill at the end of the discharge structure. The specific structure is as follows: Figure 1-Figure 6 The maximum discharge of the project is 3200m³ / s and the maximum dam height is 158.00m.

[0034] like Figure 1 , Figure 2 As shown, the diffused-type cantilevered combined cantilever sill of the present embodiment is composed of a diffused-type cantilevered sill 3 with a side wall at the outlet section of the spillway and three tooth sills arranged at the end of the diffused-type cantilevered sill 3, a side aeration sill 4 is arranged at the starting end of the diffused-type side wall, and a concrete guard tank 7 is arranged between the end of the discharge structure and the downstream riverbed.

[0035] Structural parameters and dimensions: The width of the spillway upstream of the nose sill is 14.00m. Before entering the plunging sill section, the left and right side walls of the chute spread symmetrically to both sides, and the diffusion angles α1 and α2 are both 7°. The width B of the chute at the end of the plunging sill section is 22.00m; the angle of the plunging sill section is -25°, the side wall height is 13.50m, and the difference between the end of the plunging sill and the highest water level downstream and the elevation of the downstream riverbed are 4.00m and 52.14m respectively; three tooth sills are symmetrically arranged at the end of the plunging sill, dividing the spillway outlet into four plunging areas 5-1, 5-2, 5-3 and 5-4 and three flow areas 6-1, 6-2 and 6-3. The flow widths B1, B3, B4 of the four plunging areas 5-1, 5-2, 5-3 and 5-4 are 2.3mm and 2.8mm, respectively. The lengths of the tooth sills L1, the tooth sill contraction angle β1, the arc radius R1 and the angle θ1 are 5.30m, 5°, 53.50m and -18.878° respectively; the length of the tooth sill L2, the tooth sill contraction angle β2, the arc radius R2 and the angle θ2 are 8.10m, 5°, 52.00m and -15.477° respectively; the parameters of the tooth sills corresponding to the diversion areas 6-1 and 6-3 are the same; a 50.00m long concrete guardrail 7 is set at the head where the end of the spillway connects with the downstream river channel 8.

[0036] The results of the hydraulic engineering overall model test show that under the condition of maximum discharge flow, the spillway outlet adopts a diffused combined cantilever nose sill to reduce the water level difference between its outlet and the downstream, and the generated atomization is limited to the cushion pond with little impact; the water tongue is fully diffused after the cantilever sill, and the scouring depth in the cantilever water tongue drop area 9 is only 6.40m, which is 9.30m shallower than when the cantilever sill is used alone, reducing the difficulty of energy dissipation and anti-scouring and saving engineering investment.

[0037] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A nose sill connected to a spillway, characterized in that: The bottom plate of the outlet section (1) of the spillway is connected to a sloped bottom slope that descends along the way, the width of the sloped bottom slope increases along the way in the downstream direction to form a protruding ledge (3), and the protruding ledge (3) is flush with the end of the side wall (2) of the spillway; The outlet of the protruding sill (3) is connected to the tooth sill group, and the tooth sill group includes N tooth sills arranged at intervals, which divide the outlet of the protruding sill (3) into N+1 protruding flow areas and N protruding flow areas, so that the water flow after horizontal diffusion along the way in the discharge chute forms a multi-dimensional water tongue in space; The structural parameters of any of the tooth ridges include the width, length and pick angle of the starting end, wherein: The starting width of any of the tooth sills is selected from one of B2 and B4, the value range of B2 is [0.6h, h], the value range of B4 is [0.8h, 1.5h], and h is the water depth at the end of the spillway sill under the maximum discharge condition; The length of any of the teeth is selected from L1 and L2. , , where: q is the single-width flow rate at the end of the spillway sill (3) under the maximum discharge condition; The pick angle of any of the tooth ridges is selected from one of θ1 and θ2, , , where: The value range of is [4°, 8°], and v is the flow velocity at the end of the spillway sill (3) under the maximum discharge flow condition.

2. The nose ridge according to claim 1, characterized in that: A side aeration sill (4) is arranged on the inner wall of the side wall (2) where the downward-projecting sill and the spillway meet. The side aeration sill (4) is of a sudden expansion type, and the sudden expansion width b1 has a value range of [0.20m, 0.40m].

3. The nose ridge according to claim 1, characterized in that: The range of the angle θ of the downward-facing ridge (3) is [-10°, -30°].

4. The nose ridge according to claim 1, characterized in that: The difference Δh between the terminal elevation of the downward-projecting embankment (3) and the highest water level downstream is less than 10 m.

5. The nose ridge according to claim 1, characterized in that: The diffusion angle α1 of the left wall of the downward-facing ledge (3) has a value range of [1°, 7°].

6. The nose ridge according to claim 1, characterized in that: The diffusion angle α2 of the right wall of the downward-facing ledge (3) has a value range of [1°, 7°].

7. The nose ridge according to claim 1, characterized in that: The value range of the contraction angle β of the tooth ridge is [0°, 10°].

8. The nose ridge according to claim 1, characterized in that: The teeth in the tooth ridge group are arranged in a regular alternating arrangement of large and small teeth; or, the teeth in the tooth ridge group are arranged in a manner that a plurality of large teeth are centered and a plurality of small teeth are symmetrically arranged on both sides.

9. The nose ridge according to claim 1, characterized in that: The height difference △Z between the tooth sill group and the bottom plate of the downstream river channel is greater than 20.0m.

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