Low water head dam fishway with ecological flow releasing function

Abstract

The application provides a low water head dam fishway with ecological flow discharge function, which is arranged on the side far from the water diversion gate and comprises an upstream water inlet section, a fishway and a water supplement channel, the fishway and the water supplement channel are arranged side by side at the upstream and downstream, the upstream water inlet section is connected with the fishway and the water supplement channel at the upstream, and a fish guide fence is movably connected; the fishway is a slope section, wherein a first upstream gate, multiple baffles and a first downstream gate are sequentially arranged; the water supplement channel is a slope section, multiple water supplement pipes are arranged between the fishway and the water supplement channel at the downstream, and a water supplement pipe gate is arranged in the water supplement pipe; a second upstream gate, a water supplement pipe gate control mechanism, a fish blocking weir and a second downstream gate are sequentially arranged in the water supplement channel, and the water supplement pipe gate control mechanism is used for controlling the opening degree of the water supplement pipe gate. The application has the advantages that not only the ecological flow discharge measure is perfectly combined with the fish passing building, but also the functionality of the fishway engineering is further improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of river connectivity restoration engineering, and particularly relates to a low-head dam fishway with an ecological flow discharge function. BACKGROUND

[0002] Under the environment of green hydropower and ecological hydropower, taking certain ecological compensation measures to alleviate the adverse effects brought by hydropower construction has become the standard of current hydropower construction. In order to restore river connectivity, fishway engineering is widely used. At present, the ecological negative effects brought by large hydropower are concerned, and fishway engineering is preferentially applied to large hydropower stations with a certain scale. Such hydropower stations are basically not diversion type power stations, and the downstream of the dam has stable discharge flow, which can ensure sufficient river flow, and fish can easily ascend to the dam site, so only fish passing structures need to be considered in the design process of fishway engineering.

[0003] With the steady progress of ecological hydropower construction, the ecological impact of small hydropower stations has begun to be concerned. In order to further restore the original fish habitat ecosystem, the connectivity restoration engineering of mountain stream small hydropower stations is put on the agenda. Unlike large hydropower stations, small hydropower stations are usually diversion type power stations, and the upstream flow is basically used for power generation. The ecological flow discharge at the dam site is seriously insufficient or there is no ecological flow discharge way, and there is a long distance water reduction section between the river dam and the tail water of the diversion type power station, which causes new obstacles to the upstream fish. In this case, in addition to considering the design of conventional fish passing structures, ecological flow discharge measures also need to be designed for fishway engineering. Therefore, how to scientifically add ecological flow discharge measures to the traditional fishway engineering has become a key problem to be solved. SUMMARY

[0004] In view of the above defects, the technical problem to be solved by the present application is to provide a low-head dam fishway with an ecological flow discharge function, which meets the ecological flow discharge demand of fishway engineering.

[0005] The application provides a low water head dam fishway with ecological flow discharge function, which is arranged on one side away from a water diversion gate and comprises an upstream water inlet section, a fishway and a water supplement channel, the fishway and the water supplement channel are arranged side by side at upstream and downstream, the upstream water inlet section is connected with the fishway and the water supplement channel at the upstream, and a fish guide grid is movably connected; the fishway is a slope section, wherein a first upstream gate, a plurality of baffles and a first downstream gate are sequentially arranged; the water supplement channel is a slope section, a plurality of water supplement pipes are arranged between the fishway and the water supplement channel at the downstream, and a water supplement pipe gate is arranged in the water supplement pipe; a second upstream gate, a water supplement pipe gate control mechanism, a fish blocking weir and a second downstream gate are sequentially arranged in the water supplement channel, and the water supplement pipe gate control mechanism is used for controlling the opening degree of the water supplement pipe gate.

[0006] Preferably, a rotating system is connected to the fish guide grid, and the rotating system is arranged between the fishway and the water supplement channel.

[0007] Preferably, the fish guide grid is a grid structure, and the maximum width of the grid is not greater than 30 mm.

[0008] Preferably, the upstream water inlet section is a flat slope section.

[0009] Preferably, the second downstream gate is a stoplog gate.

[0010] Preferably, the fish blocking weir is a convex structure with arc-shaped surfaces on both sides.

[0011] Preferably, the width of the water supplement channel is greater than the width of the fishway.

[0012] The application has the following advantages:

[0013] (1) The fishway function is ensured, and ecological flow discharge is realized.

[0014] (2) The fishway engineering functionality is improved, and fishway engineering downlink design is realized.

[0015] (3) The ecological flow water supplement channel is fully utilized, the fishway inlet is supplemented in multiple ways, and the fishway engineering fish attracting effect is enhanced.

[0016] (4) The fishway inlet is automatically cleaned, and the operation cost is reduced. DRAWINGS

[0017] Figure 1 is a structural schematic view of the low water head dam fishway of the application;

[0018] Figure 2 is a cross-sectional view of the position of the fish guide grid when fish guiding and pollution blocking operations are performed;

[0019] Figure 3 is a schematic view of the position of the fish guide grid when pollution cleaning operations are performed;

[0020] Figure 4 is the profile of the position of the fish guide grid during the cleaning operation;

[0021] Figure 5 is the structural schematic diagram of the outlet section of the water replenishment channel;

[0022] Figure 6 is the schematic diagram of the state of the second downstream gate during the bottom flow fish luring;

[0023] Figure 7 is the schematic diagram of the state of the second downstream gate during the drop water fish luring;

[0024] Figure 8 is the schematic diagram of the state of the second downstream gate during the maintenance of the water replenishment channel;

[0025] Element number explanation:

[0026] 1 upstream inlet section

[0027] 11 fish guide grid fixed end

[0028] 12 fixed rod

[0029] 13 fish guide grid

[0030] 14 rotating system

[0031] 2 fishway

[0032] 21 first upstream gate

[0033] 22 first downstream gate

[0034] 23 baffle

[0035] 3 water replenishment channel

[0036] 31 second upstream gate

[0037] 32 second downstream gate

[0038] 33 water replenishment pipe

[0039] 331 water replenishment pipe gate control mechanism

[0040] 332 water replenishment pipe gate

[0041] 34 fish blocking weir

[0042] 4 river blocking dam

[0043] 41 water diversion gate DETAILED DESCRIPTION

[0044] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings. These embodiments are only used to illustrate the present application, but not to limit the present application.

[0045] In the description of the present application, it should be noted that the terms "upper", "lower", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In addition, in the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0048] As Figure 1 As shown in the drawings, the present application provides a low-head dam fishway with ecological flow discharge function, which is arranged away from the water intake gate 41 on one side, comprising: an upstream water inlet section 1, a fishway 2 and a water replenishment channel 3, the fishway 2 and the water replenishment channel 3 are arranged side by side at the upstream and downstream, the wall top elevation and the bottom plate elevation of the two are consistent at the side-by-side arrangement, the width of the water replenishment channel 3 is greater than the width of the fishway 2, and the specific width is determined by the actual design of the water flow.

[0049] As Figures 1-4As shown, the upstream water inlet section 1 is a flat slope section, and is connected with the fishway 2 and the water supplement channel 3 at the upstream. The fish guide grid 13 is movably connected to the upstream water inlet section 1. The fish guide grid 13 is specifically a grid structure, and the maximum width of the grid is not greater than 30 mm. One end of the fish guide grid 13 is fixedly connected with the rotating system 14, and the rotating system 14 is arranged on the common side wall between the fishway 2 and the water supplement channel 3. When the rotating system 14 drives the movable end of the fish guide grid 13 to rotate to the side of the fishway 2, the fish guide grid 13 is arranged to be inclined at the water inlet of the fishway 2, and is mainly used for fish guiding and trash blocking. The movable end of the fish guide grid 13 is fixed to the fish guide grid fixed end 11 on the upstream side wall through the fixed rod 12, and the length of the fixed rod 12 is the same as the vertical seam width between the fish guide grid 13 and the upstream side wall. The vertical seam is used for fish to swim into the river channel to complete the overdam upstream. The fish guide grid 13 can also guide the fish entering the fishway project to descend into the water supplement channel 3, and successfully complete the downstream overdam through the water supplement channel 3, thereby improving the functionality of the fishway project. When the rotating system 14 drives the movable end of the fish guide grid 13 to rotate to the side of the water supplement channel 3, the movable end of the fish guide grid 13 is fixed to the downstream side wall through the fish guide grid fixed end 11, and is mainly used for trash blocking of the fish guide grid 13.

[0050] As shown in Figure 1 , the fishway 2 is a slope section, and the first upstream gate 21, the plurality of baffles 23 and the first downstream gate 22 are arranged in sequence in the fishway 2. The first upstream gate 21 is arranged at the water inlet of the fishway 2, and is used to block the water in the upstream water inlet section 1 from entering the fishway 2 during maintenance. The first downstream gate 22 is arranged at the water outlet of the fishway 2, and is used to block the water in the downstream river channel from entering the fishway 2 during maintenance. The baffles 23 can be selected according to the engineering characteristics.

[0051] As shown in Figure 1 and Figure 5As shown, the water supply channel 3 is a sloping section, with multiple water supply pipes 33 installed downstream of the fishway 2. Each water supply pipe 33 contains a water supply pipe gate 332. Specifically, the water supply pipes 33 are located at the unpartitioned section of the fishway 2 to supply water to the interior of the fishway. The water supply channel 3 sequentially includes a second upstream gate 31, a water supply pipe gate control mechanism 331, a fish-blocking weir 34, and a second downstream gate 32. The second upstream gate 31 is located at the inlet of the water supply channel 3 and is used for operation and maintenance. The flow rate into the water supply channel 3 is controlled by changing the opening of the second upstream gate 31. The second downstream gate 32 is a stacked beam gate located at the outlet of the water supply channel 3 and is used for operation and maintenance. The opening or stacking height of the second downstream gate 32 controls the water supply channel 3 to achieve auxiliary functions such as bottom flow attraction or waterfall attraction of fish in the side channel. The water supply pipe gate control mechanism 331 is used to control the opening degree of the water supply pipe gate 332, thereby changing the flow capacity of the water supply pipe 33. The water supply pipe 33 can work in conjunction with the second downstream gate 32 to achieve a combination of bottom flow fish attraction or waterfall fish attraction in the bypass channel and water supply inside the fishway. Both sides of the fish barrier weir 34 are curved surfaces. The upstream curved surface is used to reduce the impact force of the water flow, while the downstream curved surface is used to smoothly discharge water and accelerate the upstream flow, preventing fish from entering the water supply channel 3 from the downstream.

[0052] like Figure 1 As shown, during normal operation of the fishway project, the first upstream gate 21 and the first downstream gate 22 within fishway 2 remain open. The second upstream gate 31 within the water replenishment channel 3 adjusts its opening according to the ecological flow discharge requirements, and the second downstream gate 32 is adjusted according to the water replenishment requirements at the inlet of fishway 2. The fish guide gate 13 is fixed to the fixed end 11 of the fish guide gate located on the side of fishway 2 by a fixing rod 12. Water flows from the reservoir area of ​​dam 4 into the upstream inlet section 1, with part of the water flowing into fishway 2 and the other part flowing into water replenishment channel 3. Fish swim upstream from downstream of dam 4 through fishway 2 to the inlet of fishway 2, and under the guidance of the fish guide gate 13, they swim upstream along the side wall into the river channel, completing the upstream crossing of the dam.

[0053] When the water replenishment requirement at the inlet of fishway 2 is to attract fish through bottom flow in the bypass channel, such as Figure 6 As shown, the stacking height of the second downstream gate 32 is raised to above the water surface of the water supply channel 3 and the water supply pipe gate 332 of the water supply pipe 33 is closed. Then the second upstream gate 31 is opened, and the water flow can complete the bottom flow fish attraction in the side channel.

[0054] When the water replenishment demand at the inlet of fishway 2 is for fish attraction via a cascading waterfall in the bypass channel, close the second downstream gate 32 and proceed as follows. Figure 7 The stacking height of the second downstream gate 32 is lowered to the drop height, and then the second upstream gate 31 is opened. When the water level in the water supply channel 3 reaches the stacking height of the second downstream gate 32, the water flow can complete the side channel drop to attract fish.

[0055] When the water supplement demand of the fishway 2 inlet is the internal water supplement of the fishway, since the flow in the water supplement channel 3 is much larger than the inlet water supplement demand of the fishway 2, first, the water supplement pipe gate control mechanism 331 is adjusted to the designed opening of the water supplement pipe gate 332, then the second downstream gate 32 is adjusted to the bypass channel bottom flow fish luring state or the bypass channel drop fish luring state, and then the second upstream gate 31 is opened, so that the internal water supplement of the fishway is completed.

[0056] When the fish guide grid 13 needs to be cleaned, first, the fixed rod 12 is removed from the fish guide grid 13, then the rotating system 14 drives the fish guide grid 13 to rotate from the fishway 2 side to the water supplement channel 3 side and is fixed on the downstream fish guide grid fixed end 11, and under the impact of the water flow, the cleaning of the fish guide grid 13 is completed. After the cleaning of the fish guide grid 13 is completed, the rotating system 14 drives the fish guide grid 13 to rotate from the water supplement channel 3 side to the fishway 2 side, and the fixed rod 12 is used to fix the fish guide grid 13, so that the fish guide and trash blocking functions are continued.

[0057] When the fishway 2 needs to be maintained, first, the first upstream gate 21 is closed, and after the water in the fishway 2 is discharged, the first downstream gate 22 is closed, and then the maintenance of the fishway 2 can be started. When the maintenance is completed, the first downstream gate 22 is opened first, and then the first upstream gate 21 is opened, so that the normal operation of the fishway 2 is restored. When the water supplement channel 3 needs to be maintained, first, the second upstream gate 31 is closed, and after the water in the water supplement channel 3 is discharged, the second downstream gate 32 is completely closed, and then the maintenance of the water supplement channel 3 can be started. When the maintenance is completed, the second downstream gate 32 is opened first, and then the second upstream gate 31 is opened, so that the normal operation of the water supplement channel 3 is restored. Figure 8

[0058] In summary, compared with the traditional fishway engineering design, the advantages of the present application are as follows:

[0059] (1) Ensure the function of the fishway and realize the discharge of ecological flow. The water supplement channel is arranged beside the traditional fishway, which does not affect the structure of the fishway structure and ensures the function of the fishway to provide an upstream passage for upstream fish, and at the same time, the water supplement channel is used for the discharge of ecological flow.

[0060] (2) Improve the functionality of the fishway engineering and realize the downstream design of the fishway engineering. The water inlet of the water supplement channel and the water inlet of the fishway are arranged side by side, and the fish guide grid is arranged obliquely on the side of the fishway inlet. The fish guide grid can guide the fish entering the fishway engineering downstream into the water supplement channel, and successfully complete the downstream passage through the dam, thereby improving the functionality of the fishway engineering.

[0061] ​(3) Make full use of the ecological flow water supplement channel, and supplement water to the fishway inlet in multiple ways to enhance the fishway engineering fish attracting effect. The water outlet of the water supplement channel and the water outlet of the fishway are arranged side by side, and by changing the arrangement mode of the stoplog, the fishway can be provided with the auxiliary functions of bypass channel bottom flow fish attracting and bypass channel drop fish attracting. In addition, the water supplement pipe arranged downstream can utilize the water supplement channel to supplement water to the fishway interior, directly increase the fishway inlet flow rate, and enhance the fishway engineering fish attracting effect.

[0062] (4) Fishway inlet automatic trash cleaning, reducing operation cost. The fish guide grid arranged at the fishway engineering water inlet has the functions of fish guiding and trash grid blocking. When the trash on the fish guide grid is too much, the rotating system for controlling the fish guide grid will automatically start to rotate the fish guide grid to the water supplement channel side, and the water flow scouring effect is utilized to realize the automatic trash cleaning of the trash grid, thereby reducing the operation cost.

[0063] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and replacements can be made, and these improvements and replacements should also be considered as the protection scope of the present application.

Claims

1. A fishway with ecological flow discharge function at a low head dam, located on the side away from the water intake gate (41), characterized in that, include: The upstream inlet section (1), the fishway (2), and the water supply channel (3) are arranged side by side at the upstream and downstream ends. The upstream inlet section (1) is connected to the fishway (2) and the water supply channel (3) at the upstream end, and a fish guide grate (13) is movably connected thereto. A rotating system (14) is connected to the fish guide grate (13), and the rotating system (14) is located between the fishway (2) and the water supply channel (3). The movable end of the fish guide grate (13) can be fixed to the fixed end (11) of the fish guide grate on the upstream side wall by a fixing rod (12). The length of the fixing rod (12) is the same as the width of the vertical gap between the fish guide grate (13) and the upstream side wall. The fishway (2) is a sloping section, in which a first upstream gate (21), multiple baffles (23) and a first downstream gate (22) are arranged in sequence. The water supply channel (3) is a sloping section, and multiple water supply pipes (33) are provided between the downstream end and the fish passage (2). The water supply pipes (33) are equipped with water supply pipe gates (332). The water supply channel (3) is provided with a second upstream gate (31), a water supply pipe gate control mechanism (331), a fish barrier (34), and a second downstream gate (32) in sequence. The water supply pipe gate control mechanism (331) is used to control the opening degree of the water supply pipe gates (332).

2. The low-head dam fishway according to claim 1, characterized in that, The fish guide grid (13) has a mesh structure, and the maximum width of the mesh is no more than 30mm.

3. The low-head dam fishway according to claim 1, characterized in that, The upstream inlet section (1) is a flat slope section.

4. The low-head dam fishway according to claim 1, characterized in that, The second downstream gate (32) is a stacked beam gate.

5. The low-head dam fishway according to claim 1, characterized in that, The fish barrier (34) is a convex structure with arc-shaped surfaces on both sides.

6. The low-head dam fishway according to claim 1, characterized in that, The width of the water supply channel (3) is greater than the width of the fish passage (2).

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