A diversion and energy dissipation facility with a diversion port

Abstract

The present invention belongs to the technical field of river-blocking construction, and provides a diversion and energy dissipation facility with a diversion port, including a diversion pier main body and a plurality of outflow permeable holes of the same structure and size. The present invention can perfectly solve the impact of different flow changes in natural river channels: when the flow is small, the water flow does not need to be guided to the quiet water area, and can be discharged directly downstream from the outflow permeable hole, without causing damage to the pier body and the river channel; when the flow is large, while the outflow permeable hole is used to connect the water flow in the mainstream area with the sea flood, the unique diversion structure of the diversion pier is used to disperse the water flow into tributaries in two directions for transportation and energy dissipation; when the flow exceeds the discharge flow, the water flows over the diversion pier, which diverts the water flow horizontally and diffuses it vertically at the same time, which can greatly eliminate the residual energy of the water flow.

Description

Technical Field

[0001] The invention belongs to the technical field of river-blocking buildings and provides a diversion and energy-dissipating facility with a diversion port. Background Art

[0002] In the prior art, there are four main methods to prevent river scouring and damage: setting up diversion and energy dissipation facilities, adding energy dissipation and anti-scouring facilities, expanding the river channel, and controlling human factors. The advantages of diversion and energy dissipation facilities are:

[0003] 1) The energy dissipation is relatively sufficient, the water flow direction is relatively easy to control, and the mainstream area of ​​the downstream river can be protected by the energy dissipation buildings;

[0004] 2) It has a long history, mature technology, stable orientation, strong adaptability, and will not cause damage to the ecological environment or affect the reproduction of fish;

[0005] 3) Good adaptability to poor geological conditions;

[0006] 4) Reliable operation, good diversion and energy dissipation effect, stable downstream flow pattern, small surge, and less scouring of the riverbed and both banks;

[0007] 5) The setting is flexible. If the downstream water flow is found to be poor after the upstream project is completed and put into operation, remedial construction can be carried out later.

[0008] While diversion and energy dissipation facilities have many advantages, they also have their own or environmental limitations. The shortcomings of diversion and energy dissipation facilities in actual projects are:

[0009] 1) The application field is single and is always limited to river damming projects with medium and small flows, and the energy dissipation effect of river damming projects with large flows is poor;

[0010] 2) In order to form a stable guide, diversion and energy dissipation facilities are usually set long and thick, which not only makes the subsequent interception construction difficult, but also occupies a large area of ​​the river channel and the additional investment cost is also relatively huge.

[0011] 3) Traditional diversion and energy dissipation facilities do not pay enough attention to diversion, and have little flexibility in utilizing the width of the river, which can easily lead to unnecessary waste of energy dissipation resources.

[0012] The body design of diversion and energy dissipation facilities mainly includes diversion piers, diversion fences, groins, inclined sills and suspended fences, etc., which are single or combined energy dissipation devices. However, the existing diversion piers have significant shortcomings in practical applications:

[0013] 1) The flow pattern downstream of the diversion pier is turbulent, and the force on the pier body is complex, which can easily cause structural vibration and affect its service life and energy dissipation effect;

[0014] 2) The front of the pier body is under great pressure, which requires high strength of the pier body material and high construction cost. The diversion is purely dependent on the pier body material, which is a great test for the material strength;

[0015] 3) The pier is complex and large in size, which is not convenient for actual construction.

[0016] In order to eliminate the excess energy of the downstream water flow after it flows through the tailwater channel and reaches the floodplain and connect it smoothly with it, diversion piers are often set up to increase the energy dissipation rate, adjust the flow state of the river channel and control the direction of the water flow. Affected by many factors such as environmental terrain restrictions, only the downstream part of some rivers can be widened, so there is such a problem: when the head and flow are large, the flow velocity in the mainstream area will also increase accordingly, and the downstream widened river channel will only have a small part of the water flow flowing through the widening area due to the large widening angle, and it cannot play its due role, resulting in strong scouring damage to the downstream mainstream area due to excessive flow velocity. This is not only too expensive to maintain, but more seriously, it will cause damage to the environment and surrounding buildings. Summary of the invention

[0017] In view of the problems existing in the prior art, the present invention provides a new type of diversion and energy dissipation facility with a diversion port that has a simple design and force bearing, a reasonable structure, and an economical cost, so as to achieve the elimination of excess mechanical energy of the water flow, reduce the flow velocity, prevent scouring damage, and reduce the subsequent maintenance costs under the conditions of the same head and flow rate and without affecting the water flow rate. The structure of the present invention has the functions of guiding water flow and dissipating energy. While ensuring that the downstream water flow enters the sea smoothly and improves the disordered flow state and excessive flow velocity of the downstream water flow, it utilizes its unique body shape to eliminate excess energy through equidistantly arranged outflow permeable holes, and guides the water flow to the still water area through the diversion pier with a gradually changing height, thereby protecting the downstream riverbed and bank slope.

[0018] In order to achieve the above object, the technical solution of the present invention is:

[0019] A diversion and energy dissipation facility with a diversion port, comprising a diversion pier main body 1, and a plurality of outflow permeable holes 2 with the same structure and size;

[0020] The main body 1 of the diversion pier is composed of a top wall 11, a water-facing wall 12, a water-receiving wall 13, a bottom plate 14, a right wall 15 and a left wall 16; the left wall 16 is fixedly connected to the bank slope of the mainstream area of ​​the river channel, and the bottom plate 14 is fixedly connected to the river channel; smooth fillets are reasonably set at the connection between the top wall 11 and the water-facing wall 12 and the water-receiving wall 13 to prevent water flow from impacting and damaging the corners of the diversion pier. The fillet radius A7 is determined according to the height of the outflow permeable hole 2, and the fillet radius A7 cannot be greater than the height of the outflow permeable hole 2; the width A of the diversion pier 5 is determined according to the local water flow and the strength of the wall material; the length A4 of the diversion pier follows the principle of covering the widening area, and is determined according to the distance and angle between the position of the left wall 16 and the widening area, and the angle should not be too large. An excessively large angle not only makes it difficult for the diversion pier body 1 to play a diversion role, but also poses a great challenge to the pier body material; the height of the diversion pier body 1 gradually decreases from the left wall height H1 to the right wall height H2, which is to achieve gradual diversion of water flow from the mainstream area to the still water area and also reduces the cost.

[0021] The outlet water-permeable hole 2 is a gate-type water-permeable hole, which is equidistantly arranged at the bottom of the diversion pier body 1, and the inlet and outlet are respectively located at the water-upstream wall 12 and the water-back wall 13; the axis 21 of the outlet water-permeable hole is inclined from the water-upstream wall 12 to the water-back wall 13 toward the plane in the direction of the water flow, and the angle is an angle α, that is, the vertical line 22 of the water-upstream wall 12 and the water-back wall 13 and the axis 21 of the outlet water-permeable hole are at an angle α, and the angle α is arranged according to the angle of the diversion pier body 1 and the mainstream flow. The direction of the line is determined by the water flow line in the mainstream area, and the water flow line in the mainstream area is parallel to the axis line 21 of the outflow water tunnel. The distance A3 between the outflow water tunnels follows the length A4 of the diversion pier, which is generally 5% to 7% of the latter; the width A1 of the outflow water tunnel is determined according to the distance A3 between the outflow water tunnels, and the height of the outflow water tunnel is determined according to the width A1 of the outflow water tunnel and the water flow rate of the diversion pier, which is generally 0.5% to 1%, and the arc radius A2 is generally 1 to 3 times the height A6 of the main tunnel.

[0022] The beneficial effects of the present invention are:

[0023] 1) The diversion pier body is simple in design, easy to construct, economical in cost and easy to maintain.

[0024] 2) The force on the water-facing surface of the diversion pier is simple, the pier body fits closely with the river bank and river channel, and the pier structure is stable.

[0025] 3) When the flow rate is small, the water flow does not need to be guided to the still water area, but can be discharged directly downstream from the outflow permeable hole without causing damage to the pier and river channel.

[0026] 4) When the flow rate is large, while the outflow permeable hole is used to connect the water flow in the mainstream area with the seafloor, the water flow is dispersed into tributaries in two directions through the unique diversion structure of the diversion pier. One tributary flows in the original mainstream direction, and the other tributary gradually transitions from the mainstream area to the quiet water area, thereby increasing the single-width flow, reducing the flow rate, promoting good water transportation, guiding the water flow to discharge smoothly, and allowing the water flow to gradually and evenly diffuse without backflow, vortex or crossflow, so as to prevent the water flow from eroding the riverbed and bank slope in the quiet water area, thereby ensuring the safe operation of the water conservancy project.

[0027] 5) During over-discharge, the water flows over the diversion piers, which divert the water flow laterally and diffuse it longitudinally at the same time, greatly eliminating the residual energy of the water flow. Part of the residual energy of the water flow is dissipated in the air, and the other part is eliminated through the lateral diffusion and violent turbulence of the water flow after the water tongue falls into the sea. This ensures that the downstream water flow is smoothly introduced into the downstream while dispersing the kinetic energy of the downstream water flow, minimizing the damage to the downstream riverbed and bank slope, thereby reducing the protection work downstream, bringing greater economic benefits, and avoiding the destruction of the living environment of downstream aquatic animals due to violent water turbulence. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A three-dimensional diagram of a diversion and energy dissipation facility with a diversion port according to the present invention;

[0029] Figure 2 , Figure 3 , Figure 4 and Figure 5 They are the front view, bottom view, rear view and right view of the diversion and energy dissipation facility with diversion outlets.

[0030] Figure 6 This is a three-dimensional perspective view of the outflow water tunnel.

[0031] In the figure: 1 the main body of the diversion pier; 2 the outlet water hole;

[0032] 11 top wall; 12 water-facing wall; 13 water-receiving wall; 14 bottom plate; 15 right wall; 16 left wall;

[0033] 21 axis of outflow water tunnel; 22 vertical line;

[0034] H1 left wall height; H2 right wall height; A1 outflow water hole width; A2 arc radius; A3 outflow water hole spacing; A4 diversion pier length; A5 diversion pier width; A6 main hole height; A7 fillet radius; angle α. DETAILED DESCRIPTION

[0035] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and technical solutions.

[0036] like Figure 1As shown, the novel diversion and energy dissipation facility with diversion ports of the present invention comprises a diversion pier body 1 and an outflow permeable hole 2.

[0037] like Figure 2 to Figure 5 As shown, the new diversion and energy dissipation facility with diversion ports in this embodiment includes a diversion pier body 1 (including a top wall 11, a water-facing wall 12, a water-receiving wall 13, a bottom plate 14, a right wall 15, and a left wall 16) and 15 outflow permeable holes 2 of the same structure (the outflow permeable hole axis 21 and the vertical line 22). The left wall 16 is fixedly connected to the bank slope of the mainstream area of ​​the river channel, and the bottom plate 14 is fixedly connected to the river channel; smooth fillets are reasonably set at the connection between the top wall 11 and the water-facing wall 12 and the water-receiving wall 13 to prevent water flow from impacting and damaging the corners of the diversion pier, and the fillet radius A7 is 0.2m; the diversion pier width A5 is 1m; the diversion pier length A4 is 48m; the height of the diversion pier body 1 gradually decreases from the left wall height H1 to the right wall height H2, and the left wall height H1 and the right wall height H2 are 1m and 0.5m respectively.

[0038] like Figure 6 As shown, the outflow permeable tunnel 2 is a gate-type permeable tunnel, which is equidistantly arranged at the bottom of the diversion pier body 1, and the inlet and outlet are respectively located at the front wall 12 and the back wall 13. The included angle α between the vertical line 22 of the front wall 12 and the back wall 13 of the diversion pier and the axis 21 of the outflow permeable tunnel is 30°, and the water flow line in the mainstream area is parallel to the axis 21 of the outflow permeable tunnel, and the axis spacing A3 of adjacent outflow permeable tunnels is 3m; the axis of each permeable hole is inclined from the front surface of the diversion wall body to the back surface toward the plane of the downstream direction, with an angle of 30°; the width A1 of the outflow permeable tunnel is 0.4m, the arc radius A2 is 0.2m, and the main hole height A6 is 0.1m.

[0039] The working process of the present invention in conjunction with the example is as follows:

[0040] During flood discharge, the water flows down along the spillway. Before reaching the sea, it passes through the headwater wall 12 and the top wall 11 in the same direction as the incoming flow, combined with the diversion pier 1 and the outflow permeable tunnel 2. The downstream water flow is divided into three parts, namely, the tributary above the pier body, the tributary in the tunnel and the tributary directed to the still water area. Among them, the water-facing wall 12 as a vertical surface helps to reduce the impact stress of the incoming flow and plays a role in eliminating residual energy. The diversion structure between the diversion pier 1 and the outflow permeable tunnel 2 divides the downstream water flow into three tributaries, of which one tributary is carried to the downstream sea by the water-facing wall 12 and the top wall 11, effectively utilizing the longitudinal space of the diversion pier 1, so that the energy dissipation in the air is significantly enhanced, during which part of the energy is offset by the potential energy, and the residual energy is gradually eliminated by the downstream wide river channel after falling; the energy of the second tributary is directly dissipated by the outflow permeable tunnel 2, and then diffused and eliminated laterally in the downstream wide river channel; the third tributary is diverted to the still water area by the diversion pier 1, so that a gradually flowing water body is generated in the still water area, and the tributary swirls and diffuses in it, which not only reduces the single-width flow but also eliminates the residual energy. After passing through the diversion pier 1, the three downstream tributaries diffuse longitudinally and transversely respectively, which greatly enhances the energy dissipation effect, reduces the single-width flow, reduces the construction cost, improves the downstream ecological environment, greatly weakens the high-speed water energy, and ensures that the downstream riverbed, slope and buildings are protected from scouring and damage, effectively solving the problem of energy dissipation and anti-scouring in the river channel downstream of the discharge structure.

[0041] The experimental research shows that the water level in the reservoir is 107.40m and the flow rate is 268.16m 3 / s, according to the design of this embodiment, the water heads and flow velocities of the original design scheme, i.e., without diversion and energy dissipation facilities, and the recommended scheme, i.e., with diversion and energy dissipation facilities, are measured under the same water level and flow rate and are listed in Table 1. The water flow of the upstream section of the embodiment is divided into three parts, i.e., left, middle, and right, according to its width. The downstream section is divided into two areas, i.e., a mainstream area and a still water area. The three parts of the mainstream area correspond to the three parts of the upstream section, and the two parts of the still water area are newly added parts. A flow velocity and a water head are tested for each part, and a total of 16 groups of flow velocities and 16 groups of water heads are tested.

[0042] Table 1 Head and flow rate table of two types of diversion and energy dissipation facilities placement methods

[0043]

[0044] Comparison of the results showed that the new diversion and energy dissipation facility with a diversion port of the present invention redistributed the water flow, and the flow, head and flow velocity in the mainstream area decreased, while the flow, head and flow velocity in the still water area increased; at the same time, the longitudinal and lateral diffusion effects of the three tributaries were good, the water flow in the still water area was turbulent and the water surface fluctuated violently, the water flow fluctuation amplitude near the sea flood downstream of the diversion and energy dissipation facility was smaller, and the energy dissipation effect was significant.

[0045] The novel diversion and energy dissipation facility of the present invention can be used for diversion and energy dissipation between the end of the tailwater channel and the downstream sea floodplain, and can effectively solve the problem of connection between the discharge structure and the water surface of the natural river channel, and can redistribute the flow velocity, reduce the flow velocity in the mainstream area, improve the flow state of the downstream water flow, prevent scouring and damage in the downstream of the mainstream area, and ensure the safety of water conservancy engineering facilities such as discharge structures, gabions and slope protection, and realize the gradual transition from the mainstream area to the still water area. At the same time, it can avoid the ecological and environmental damage caused by the violent turbulence of the downstream water flow state and the generation of rapid shock waves due to excessive flow velocity.

Claims

1. A diversion and energy dissipation facility with a diversion port, characterized in that: The diversion and energy dissipation facility with a diversion port comprises a diversion pier main body (1), and a plurality of outflow permeable holes (2) of the same structure and size; The diversion pier body (1) is composed of a top wall (11), a water-facing wall (12), a water-retaining wall (13), a bottom plate (14), a right wall (15) and a left wall (16); the left wall (16) is fixedly connected to the bank slope of the mainstream area of ​​the river channel, and the bottom plate (14) is fixedly connected to the river channel; a smooth fillet is set at the connection between the top wall (11) and the water-facing wall (12) and the water-retaining wall (13); the fillet radius (A7) is determined according to the height of the outflow water hole (2), and the fillet radius (A7) is not greater than the height of the outflow water hole (2); the diversion pier width (A5) is determined according to the local water flow and the strength of the wall material; the diversion pier length (A4) follows the principle of covering the widening area, and is determined according to the distance and angle between the position of the left wall (16) and the widening area; the height of the diversion pier body (1) gradually decreases from the left wall height (H1) to the right wall height (H2); The outlet water permeable holes (2) are gate-type water permeable holes, which are arranged at equal intervals at the bottom of the diversion pier body (1), and the inlet and outlet are respectively located at the water-facing wall (12) and the water-retaining wall (13); the axis (21) of the outlet water permeable hole is inclined toward the plane in the direction of the water flow from the water-facing wall (12) to the water-retaining wall (13), and the angle is an included angle (α), that is, the vertical line (22) between the water-facing wall (12) and the water-retaining wall (13) and the axis (21) of the outlet water permeable hole form an included angle (α), and the included angle (α) is determined according to the diversion pier. The main body (1) is arranged at an angle determined by the direction of the main flow line, and the water flow line in the main flow area is parallel to the axis (21) of the outflow permeable tunnel, and the distance (A3) between the outflow permeable tunnels is 5% to 7% of the length (A4) of the diversion pier; the width (A1) of the outflow permeable tunnel is determined according to the distance (A3) between the outflow permeable tunnels, the height of the outflow permeable tunnel is determined according to the width (A1) of the outflow permeable tunnel and the water flow rate of the diversion pier, the water flow rate is 0.5% to 1%, and the arc radius (A2) is 1 to 3 times the height (A6) of the main tunnel.

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