Device for controlling water depth of fishway pond chamber and design method

Abstract

The invention relates to the technical field of water conservancy projects, in particular to a device for controlling the water depth of a fishway pool chamber and a design method.The design method of the device for controlling the water depth of the fishway pool chamber comprises the steps that the minimum design water level of the upstream of a main fishway and the minimum submerging water depth of an abrupt slope fishway outlet are calculated according to the relation curve of the water depth of the main fishway and the passing efficiency; the allowable running water depth range of the main fishway with the high fish passing efficiency is determined, the optimal running water depth range of an abrupt slope fishway inlet with the high fish passing efficiency is determined, if the upstream water level of the fishway is low, the flow of the main fishway is influenced, and fish migration is influenced, only the flow needs to be supplemented into the fishway through an adjustable gate; and when the water depth of the main fishway exceeds the running water level limit and fish migration is influenced, the outlet elevation of the steep-slope fishway is raised, so that the flow entering the main fishway is reduced, and the water depth of the main fishway is controlled to be within the determined running water depth range.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy engineering, and in particular to a device for controlling the water depth of a fishway pool and a design method thereof. Background Art

[0002] In order to develop hydropower resources and improve the inherent defects of uneven distribution of water resources, a large number of hydraulic structures such as dams have been built in rivers. Although these structures have played a great role in flood control, irrigation, power generation, etc., they also block the flow of rivers, making it impossible for most fish with migratory or semi-migratory habits to swim upstream to spawn, forage, etc., and even worse, it will cause the loss of fish genetic diversity. In order to restore the connectivity of rivers and enable migratory fish to swim upstream normally, fishways are a very effective measure. Fishways are artificial water troughs built on sluices or dams for fish to migrate. Fish in fishways have to rely on their own strength to overcome the flow rate and swim upstream independently. Therefore, considering the upstream habits of fish to design fishways is a very technically demanding task. For hundreds of years, people have done a lot of research and practice on fishway construction, and the level of understanding and technology has been constantly developing and improving.

[0003] The water depth affects the fish passing efficiency. For example, when the water depth is in the range of 0.50-1.00m, the fish passing efficiency is high; when the water depth is greater than 1.0m, the fish passing efficiency decreases rapidly. When the water depth is in the range of 1.15-1.50m, the passing efficiency is still within an acceptable range; when the water depth in the pool chamber is in the range of 1.75-2.00m, the fish passing efficiency index is lower than 0.3, which is about 3-4 times lower than the fish passing efficiency index when the water depth is in the range of 0.50-1.00m. The fishway passing efficiency is extremely low. It can be seen that the gate opening method in the prior art is difficult to simultaneously achieve the purpose of controlling the fishway depth and ensuring the normal migration of fish. Summary of the invention

[0004] In order to solve the above problems and improve the fish passing efficiency when the gate is opened, the present invention provides the following technical solutions:

[0005] A device for controlling the water depth of a fishway pool comprises a main fishway, wherein a flow-isolating pier is arranged in the middle of the main fishway, and the upstream section of the main fishway is divided into an A-zone channel and a B-zone channel by the flow-isolating pier. A movable gate is arranged on the upstream water inlet of the A-zone channel, and a superimposed gate is arranged on the upstream water inlet of the B-zone channel. The superimposed gate is composed of a fixed section at the bottom and a movable section at the top. A steep slope fishway is installed through the movable section of the superimposed gate, and the other end of the steep slope fishway enters the B-zone channel.

[0006] As a further preferred embodiment, the following design steps are included:

[0007] Step S1, determining the bottom elevation at the exit of the steep slope fishway according to the lowest design water level upstream of the main fishway and the minimum submerged water depth Hcx at the exit of the steep slope fishway;

[0008] Step S2, verifying that the vertical height of the baffle in the steep slope fishway + the bottom elevation at the exit of the steep slope fishway is greater than the highest design water level upstream of the main fishway to ensure that the baffle in the steep slope fishway is not submerged;

[0009] Step S3, checking whether the flow rate Qb of the steep slope fishway is less than the flow rate Qz of the main fishway, so as to ensure that the water depth of the main fishway corresponding to the flow rate is within the optimal allowable operating depth range;

[0010] Step S4, determining the fish passing efficiency based on the water depth of the main fishway;

[0011] Step S5: Check whether the optimal minimum flooding depth of the main fishway meets the connection with the steep slope fishway inlet water level and the minimum flooding depth requirements through a model test. If not, it means that the flow rate discharged through the steep slope fishway is insufficient, and it is necessary to open the superimposed gate to adjust the auxiliary flow rate to meet the requirements;

[0012] Step S6, determining the maximum operating water depth range of the main fishway with high fish passing efficiency based on the water depth of the main fishway, and verifying through a model test whether the water depth meets the requirement of covering the optimal maximum submerged water depth of the steep slope fishway entrance;

[0013] Step S7, determining the allowable operating water depth range of the main fishway with higher fish passing efficiency Hzy according to the water depth of the main fishway, and verifying whether the water depth meets the requirement of the optimal maximum submerged water depth Hjd of the inlet of the steep slope fishway through a model test;

[0014] Step S8, determine the operation scheduling mode;

[0015] Step S9: Fix the determined operation procedure into the system.

[0016] As a further preferred embodiment, step S1 is specifically as follows:

[0017] Step S11, determining the optimal operating water depth of the main fishway and the optimal submerged water depth of the entrance and exit of the steep slope fishway;

[0018] Step S12, carrying out model tests when the upstream lowest water level of the main fishway in the upstream reservoir is 214.70m, and the upstream highest water level of the main fishway 1 is 214.82m, 214.91m, and 215.00m;

[0019] Step S13, according to the design result of step S12, finely control the movable gate and the superimposed gate, and finally determine the bottom elevation data at the exit of the steep slope fishway;

[0020] Step S14, verifying the bottom elevation result at the exit of the steep slope fishway in step S13.

[0021] As a further preferred embodiment, step S2 is specifically as follows:

[0022] Step S21, setting the vertical height of the baffle in the steep slope fishway;

[0023] Step S22, the actual bottom elevation data of the steep slope fishway plus the vertical height of the baffle 0.93m are added to obtain the sum of the data;

[0024] The sum of the data obtained in step S23 and step S22 is compared with the data of the bottom elevation at the steep slope fishway exit obtained in step S13 to obtain a result. If the former is greater than the latter, the bottom elevation at the steep slope fishway exit meets the design requirements.

[0025] As a further preferred embodiment, step S3 is specifically as follows:

[0026] Step S31, determining the highest design water level upstream of the main fishway, and checking whether the flow rate Qb of the steep slope fishway is less than the flow rate Qz of the main fishway when the outlet of the steep slope fishway is at the maximum flooding depth;

[0027] Step S32: If the result obtained from step S31 is Qb>Qz, it means that it is necessary to adjust the bottom elevation of the overlapping gate in the channel of area B to reduce the submerged water depth Hcd of the steep slope fishway outlet so that Qb≤Qz can meet the design requirements.

[0028] As a further preferred embodiment, step S4 is specifically as follows:

[0029] Step S41, determining the main fishway with higher fish passing efficiency as the optimal operating water depth range through the efficiency relationship curve;

[0030] Step S42: determine the optimal operating water depth range of the inlet of the steep slope fishway with higher fish passing efficiency.

[0031] As a further preferred embodiment, step S5 is specifically as follows:

[0032] Step S51, determining the maximum operating water depth of the main fishway with high fish passing efficiency based on the water depth of the main fishway and the passing efficiency relationship curve in step S41;

[0033] Step S52: Verify whether the maximum operating water depth range covers the optimal maximum submerged water depth of the entrance of the steep slope fishway based on the water depth of the main fishway and the passing efficiency relationship curve in step S41 and the model test.

[0034] As a further preferred embodiment, step S6 is specifically as follows:

[0035] Step S61, determining the allowable operating water depth of the main fishway with higher fish passing efficiency based on the water depth of the main fishway and the passing efficiency relationship curve in step S41;

[0036] Step S62, verifying whether the water depth of the main fishway, the passing efficiency relationship curve in step S41 and the model test meet the requirements of the maximum submerged water depth of the steep slope fishway entrance.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] A flow-isolating pier is set at the upstream of the fishway, and the upstream of the fishway is divided into channel A and channel B by the flow-isolating pier. Gates are set upstream of the two channels respectively. The gate in channel A is a movable gate, and the gate in channel B is a composite gate. The composite gate consists of two opening and closing parts, and a Daniel-type steep slope fishway is set on the upper movable section. The water depths of the main fishway and the steep slope fishway are controlled by design methods. First, the bottom elevation at the exit of the steep slope fishway is determined by the lowest design water level upstream of the main fishway and the minimum submerged depth at the exit of the steep slope fishway. After the bottom elevation is verified, the fish passing efficiency is determined. Then, a model test is used to verify whether the optimal minimum submerged depth of the main fishway meets the requirements of connection with the inlet water level of the steep slope fishway and the minimum submerged depth. If not, This indicates that the flow discharged through the steep slope fishway is not enough at this time, and it is necessary to open the superimposed gate to adjust the auxiliary flow to meet the requirements, and then the water depth of the main fishway is used to determine the maximum operating water depth range of the main fishway with high fish passing efficiency. If the water level upstream of the main fishway is low, affecting the flow of the main fishway, and the low flow affects the fish migration, the adjustable gate can be used to supplement the flow into the main fishway. If the water level upstream of the main fishway is high, the water depth of the main fishway exceeds the upper limit of the operating water level, which will also affect the fish migration. The superimposed gate is used to raise the outlet elevation of the steep slope fishway to reduce the flow entering the main fishway and control the water depth of the main fishway within the determined operating water depth range. Compared with the prior art, the gate opening method of the present invention can achieve the purpose of controlling the depth of the fishway and ensuring the normal migration of fish. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A three-dimensional schematic diagram of a device for controlling the water depth of a fishway chamber provided in an embodiment of the present invention;

[0040] Figure 2 A schematic top view of a device for controlling the water depth of a fishway chamber provided in an embodiment of the present invention;

[0041] Figure 3 A schematic diagram of a device for controlling the water depth of a fishway chamber provided by an embodiment of the present invention when the device is disconnected from the main fishway and looking at a movable gate and a superimposed gate;

[0042] Figure 4 A flow chart of design steps of a design method in an embodiment of the present invention;

[0043] Figure 5 A diagram for dividing the optimal operation and allowable operation water depths of the main fishway in the design method in an embodiment of the present invention;

[0044] Figure 6 A curve diagram showing the relationship between the submerged water depth at the entrance of a steep slope fishway and the passing rate in the design method according to an embodiment of the present invention;

[0045] Figure 7 This is a statistical comparison diagram of the successful upstream rate of the fishway before and after water replenishment in working condition 1 in the embodiment of the present invention;

[0046] Figure 8 It is the design principle and each design code in the implementation mode of the present invention.

[0047] In the figure: 1, main fishway; 2, flow-blocking pier; 3, channel of area A; 4, channel of area B; 5, movable gate; 6, superimposed gate; 61, fixed section; 62, movable section; 63, steep slope fishway. DETAILED DESCRIPTION

[0048] The above and other embodiments and advantages of the present invention are described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments.

[0049] In one embodiment, Figure 1-Figure 8 As shown: This embodiment provides a device for controlling the water depth of a fishway pool, comprising a main fishway 1, a flow-isolating pier 2 is provided in the middle of the main fishway 1, and the upstream section of the main fishway 1 is divided into an A-zone channel 3 and a B-zone channel 4 by the flow-isolating pier 2. A movable gate 5 is provided on the upstream water inlet of the A-zone channel 3, and a superimposed gate 6 is provided on the upstream water inlet of the B-zone channel 4. The superimposed gate 6 consists of a fixed section 61 at the bottom and a movable section 62 at the top. A steep slope fishway 63 is installed through the movable section 62 of the superimposed gate 6, and the other end of the steep slope fishway 63 enters the B-zone channel 4.

[0050] It should be noted that the flat lifting gate and Daniel steep slope fishway in the device are existing components and do not belong to the scope of the present invention. They can be designed according to their own specifications, so they will not be described here. Here we mainly introduce the basic design principles and specific design methods related to the device of the present invention.

[0051] The design method of the device for controlling the water depth of a fishway chamber disclosed in the present invention comprises the following design steps:

[0052] Step S1, determining the bottom elevation at the exit of the steep slope fishway 63 based on the lowest design water level upstream of the main fishway 1 and the minimum submerged water depth at the exit of the steep slope fishway 63;

[0053] Step S2, verifying that the vertical height of the baffle in the steep slope fishway 63 + the bottom elevation at the exit of the steep slope fishway 63 is greater than the highest design water level upstream of the main fishway 1 to ensure that the baffle in the steep slope fishway 63 is not submerged;

[0054] Step S3, checking whether the flow rate Qb of the steep slope fishway 63 is less than the flow rate Qz of the main fishway 1, so as to ensure that the water depth of the main fishway 1 corresponding to the flow rate is within the optimal allowable operating depth range;

[0055] Step S4, determining the fish passing efficiency based on the water depth of the main fishway 1;

[0056] Step S5, verifying through model test whether the optimal minimum submerged depth of the main fishway 1 meets the connection with the inlet water level of the steep slope fishway 63 and the requirements of the minimum submerged depth. If not, it means that the flow discharged through the steep slope fishway 63 is insufficient, and the superimposed gate 6 needs to be opened to adjust the auxiliary flow to meet the requirements;

[0057] Step S6, determining the maximum operating water depth range of the main fishway with high fish passing efficiency based on the water depth of the main fishway 1, and verifying through a model test whether the water depth meets the requirement of covering the optimal maximum submerged water depth of the entrance of the steep slope fishway 63;

[0058] Step S7, determining the allowable operating water depth range of the main fishway 1 with higher fish passing efficiency based on the water depth of the main fishway 1, and verifying through a model test whether the water depth meets the requirement of the optimal maximum submerged water depth of the inlet of the steep slope fishway 63;

[0059] Step S8, determine the operation scheduling mode;

[0060] Step S9: Fix the determined operation procedure into the system.

[0061] Wherein, step S1 is specifically as follows:

[0062] Step S11, determining the optimal operating water depth of the main fishway 1 and the optimal submerged water depth of the inlet and outlet of the steep slope fishway 63.

[0063] Specifically, the operating water depth of the main fishway 1 pool is divided into an optimal operating water depth and an allowable operating water depth. The optimal operating water depth and the allowable operating water depth are determined by the relationship curve between the water depth of the main fishway 1 pool and the fish passage effect of the fishway through a biohydraulic model test or prototype observation (e.g. Figure 5 shown).

[0064] Specifically, the flooding depth at the entrance of the steep slope fishway 63 is divided into a minimum flooding depth Hjx and a maximum flooding depth Hjd (e.g. Figure 8 shown).

[0065] Step S12: Carry out model tests at four water levels: the lowest upstream water level of the main fishway 1 in the upstream reservoir is 214.70 m (the lowest upstream water level of the fishway), and the highest upstream water levels of the main fishway 1 are 214.82 m, 214.91 m, and 215.00 m (the highest upstream water level of the fishway); when the upstream water level of the steep slope fishway 63 is 214.70 m (the lowest upstream water level of the fishway) and the water depth is 1.70 m, the detected water flow rate is 0.199 m 3 / s, at this time, the water depth in the main fishway 1 pool is 0.5m, the inlet of the steep slope fishway 63 is submerged at a depth of 0.47m, when the water level upstream of the steep slope fishway 63 is 214.82m, the water depth is 1.82m, and the detected water flow rate is 2.87m 3 / s, at this time, the water depth in the main fishway 1 pool is 0.75m, the inlet of the steep slope fishway 63 is submerged at a depth of 0.55m, and the outlet of the steep slope fishway 63 is submerged at a depth of 0.52m. When the water level upstream of the steep slope fishway 63 is 214.91m and the water depth is 1.91m, the detected water flow rate is 0.375m 3 / s, at this time, the water depth in the main fishway 1 pool reaches 1.00m, the inlet of the steep slope fishway 63 is submerged at a depth of 0.70m, and the outlet of the steep slope fishway 63 is submerged at a depth of 0.6m. When the upstream water level of the steep slope fishway 63 is 215m (the highest water level upstream of the fishway operation) and the upstream water depth of the steep slope fishway 63 is 2m, the detected water flow rate is 0.463m 3 / s, and the water flow rate is 0.463m 3 / s, the water depth in the pool of the main fishway 1 reaches 1.25m, the inlet submerged depth of the steep slope fishway 63 is 0.85m, and the outlet submerged depth of the steep slope fishway outlet reaches 0.62m. In summary, the experiment shows that the higher the upstream water level of the steep slope fishway 1, the deeper the water depth upstream of the steep slope fishway 1, and the greater the water flow; conversely, the lower the upstream water level of the steep slope fishway 1, the shallower the water depth upstream of the steep slope fishway 1, and the smaller the water flow.

[0066] The conclusion drawn from the above experiment is that the water level and flow rate of the steep slope fishway 1 are determined by the water level of the upstream reservoir area, and the greater the water flow rate, the deeper the water depth in the main fishway 1 pool, the deeper the inlet submerged water depth of the steep slope fishway 63, and the deeper the outlet submerged water depth of the steep slope fishway 63; conversely, the smaller the water flow rate, the shallower the water depth in the main fishway 1 pool, the shallower the inlet submerged water depth of the steep slope fishway 63, and the shallower the outlet submerged water depth of the steep slope fishway 63. Therefore, by controlling the water flow rate, not only the water depth of the main fishway 1 can be controlled, but also the outlet submerged water depth of the steep slope fishway 63 and the inlet submerged water depth of the steep slope fishway 63 can be controlled. In order to control the water flow, the present invention designs a movable gate 5 in the main fishway 1. In order to make the flow control more flexible, a composite gate 6 is designed in the channel 4 of zone B. The water flow can be controlled by controlling the opening and closing size of the movable gate 5 and the composite gate 6. According to Table 1, in particular, by controlling the opening and closing size of the composite gate 6, the water flow can be adjusted. According to the above experimental relationship, when the water flow is adjusted, the water depth of the main fishway 1 can also be regulated. According to the above experimental relationship, the inlet submerged water depth and the outlet submerged water depth of the steep slope fishway 63 can also be regulated. In order to make the design of the composite gate 6 more flexible, the composite gate 6 is set to an upper and lower part, that is, according to Figure 1 , Figure 3 As shown, the composite gate 6 consists of a fixed section 61 at the bottom and a movable section 62 at the top. The bottom end of the fixed section 61 is fixed in the channel 4 of zone B, and the steep slope fishway 63 is fixed on the movable section 62, thereby determining the opening and closing principle of the composite gate 6: the water flow rate can be controlled by adjusting the opening and closing distance of the steep slope fishway 63 in the channel 4 of zone B relative to the fixed section 61, that is, when adjusting the movable section 62, the movable section 62 leads the steep slope fishway 63 to adjust the opening and closing distance relative to the fixed section 61. If the water level upstream of the main fishway 1 is high, the flow rate flowing into the main fishway through the steep slope fishway 63 makes the water depth of the main fishway 1 exceed the upper limit of the operating water level, then it is necessary to use the movable section 62 to increase the opening and closing degree of the steep slope fishway 63 relative to the fixed section 61, so that the flow rate of water entering the channel 4 in area B becomes smaller. At this time, the amount of water entering the main fishway 1 from the channel 4 in area B is also lower, so as to control the water depth range of the main fishway 1 and the steep slope fishway 63 to become smaller; conversely, if the water level upstream of the main fishway 1 is low, the flow rate flowing into the main fishway through the steep slope fishway 63 If the main fishway 1 is not sufficient to support the main fishway 1 to reach the lower limit of the operating water level, it is necessary to use the movable section 62 to reduce the opening and closing degree of the steep slope fishway 63 relative to the fixed section 61. At this time, the water flow entering the channel 4 in area B becomes larger, and the water is replenished from the channel 4 in area B to the main fishway 1 to control the water depth range of the main fishway 1 and the steep slope fishway 63 to become deeper. When the movable gate 5 is opened to release water, it is only necessary to adjust the height of the steep slope fishway 63 in the channel 4 in area B to control the flow of the main fishway 1, and the movable gate 5 can be in normal water release.

[0067] Based on the above, this practical method has carried out a fine control study on the movable gate 5 and the composite gate 6 through experimental data. The specific test conditions are shown in Table 1:

[0068] like Figure 6 As shown, according to the test conditions and step S12, the relationship between the submerged water depth at the entrance of the steep slope fishway 63 and the fish passage rate is as follows: when the water depth in the channel 4 of area B is 0.70m, it is the optimal submerged water depth at the entrance of the steep slope fishway 63, and the passage rate of fish migrating from the steep slope fishway 63 is as high as 87.5%; if the fish passage rate of the steep slope fishway 63 is to be ensured to be around 70%, the minimum submerged water depth Hjx of the entrance of the steep slope fishway 63 is ≥0.60m, and the maximum submerged water depth Hjd ≤0.85m.

[0069] According to the above data, by adjusting the opening amplitude of the movable section 62 on the overlapping gate 6 relative to the fixed section 61, the wading depth of the steep slope fishway 63 in the channel 4 of zone B can be regulated. By adjusting the inlet water depth of the steep slope fishway 63 in the channel 4 of zone B to 0.70m in this way, the pass rate of fish migrating from the steep slope fishway 63 is as high as 87.5%. When the minimum submerged water depth Hjx at the inlet of the steep slope fishway 63 in the channel 4 of zone B is adjusted to 0.60m and the maximum submerged water depth Hjd ≤ 0.85m, the pass rate of fish migrating from the steep slope fishway 63 is about 70%. The main fishway reaches the lower limit of the operating water level. This is exactly the case. If the water level upstream of the fishway is low, the amount of water flowing into the fishway is not enough to support the main fishway (channel 3 in area A) to reach the lower limit of the operating water level. The movable section 62 brings the steep slope fishway 63 to adjust the opening and closing amplitude relative to the fixed section 61, so that the inlet water depth of channel 4 in area B (0.70m, maximum submerged depth Hjd≤0.85m, minimum submerged depth Hjx≥0.60m respectively) can be adjusted. In this way, when the water depth in channel 4 in area B is controlled at 0.6m to 0.85m, not only can water be discharged downstream through the main fishway 1, but it can also ensure that fish migrate upstream from the steep slope fishway 63. In order to meet this design requirement, the above three wading depths of the steep slope fishway 63 in the channel 4 of zone B are designed (the water depth of the water inlet is 0.70m, the maximum submerged water depth of the water inlet Hjd≤0.85m, and the minimum submerged water depth of the water inlet Hjx≥0.60m).

[0070] (Table 1: Water level change condition table upstream of steep slope fishway 63)

[0071]

[0072] Step S13, according to the design result of step S12, finally determining the bottom elevation data at the exit of the steep slope fishway 63;

[0073] Specifically, the design high water level of the main fishway 1 is 215.0m for the normal water level, and the design low water level is 214.70m (considering the water level fluctuation of 0.3m when the power station is generating electricity). Considering that the adult height of the four major carps is about 0.15-0.20m, the minimum submerged depth Hcx at the exit of the steep slope fishway 63 is twice the body height of the fish, and the bottom elevation at the exit of the steep slope fishway 63 is preliminarily determined to be: the lowest design water level upstream of the fishway - the minimum submerged depth Hcx at the exit of the fishway, that is, 214.70m-2×(0.15-0.2m)=214.30-214.40m. (Formula 1)

[0074] Step S14, verifying the bottom elevation result at the exit of the steep slope fishway 63 in step S13.

[0075] Specifically, according to the calculation result of formula 1, the bottom elevation at the exit of the steep slope fishway 63 is set to 214.38m, and then further checked and determined through the following steps S2 to S6:

[0076] Step S2 is specifically as follows:

[0077] Step S21, setting the vertical height of the inner baffle of the steep slope fishway 63 to 0.93m;

[0078] Step S22, the actual bottom elevation data of the steep slope fishway 63 is added to the vertical height of the baffle 0.93m to obtain the sum of the data;

[0079] The sum of the data obtained in step S23 and step S22 is compared with the data of the bottom elevation at the exit of the steep slope fishway 63 obtained by (formula 1) in step S13 to obtain a result. If the former is greater than the latter, the bottom elevation at the exit of the steep slope fishway 63 meets the design requirements.

[0080] Specifically, the vertical height of the inner baffle of the steep slope fishway 63 is set to 0.93m; the bottom elevation at the exit of the steep slope fishway 63 is set to 214.38m, and calculation shows that: 0.93+214.38=215.31m> the maximum design water level of the steep slope fishway 63 is 215m. At this time, the sum of the height of the inner baffle of the steep slope fishway 63 and the bottom elevation at the exit of the steep slope fishway 63 meets the design requirements.

[0081] Step S3 is specifically as follows:

[0082] Step S31: According to Table 2 and Figure 5 , determine the highest design water level upstream of the main fishway 1, when the outlet of the steep slope fishway 63 is at the maximum submerged depth (0.62m), check whether the flow rate Qb of the steep slope fishway 63 is less than the flow rate Qz of the main fishway 1, so as to ensure that the water depth of the main fishway 1 corresponding to the flow rate is the optimal or allowed operating depth;

[0083] Step S32, if the result obtained from step S31 is Qb>Qz, according to the reason for flow control, it can be known that the flow rate of channel 4 in area B is large, and the wading amount of steep slope fishway 63 in channel 4 in area B is deep, that is, the opening amplitude of the superimposed gate 6 (the opening amplitude of the active section 62 with the steep slope fishway 63 relative to the fixed section 61) is large. At this time, it is necessary to adjust the elevation of the superimposed gate 6 in channel 4 in area B (that is, the opening and closing degree of the steep slope fishway 63 with the active section 62 in the superimposed gate 6 becomes smaller relative to the fixed section 61) to reduce the submerged water depth Hcd of the outlet of the steep slope fishway 63, so that Qb≤Qz meets the design requirements, so as to ensure that when the main fishway 1 (channel 3 in area A) is drained, the fish in it can migrate upstream through channel 4 in area B and steep slope fishway 63. Compared with the prior art, the gate opening method of the present invention can achieve the purpose of controlling the depth of the fishway and ensuring the normal migration of fish.

[0084] (Table 2: Relationship between fishway flow and water depth at characteristic locations)

[0085]

[0086] Specifically, it can be seen from Table 2 that the upstream is the highest design water level of the fishway, and the outlet of the steep slope fishway 63 is the best maximum submerged water depth Hcd = 0.62m (at this time Hcj = 0.85m), Qb = 0.463 (m 3 / s), the corresponding main fishway 1 pool water depth is 1.25m. Figure 5 From the fish passage rate relationship diagram, it can be seen that the water depth Hz of the pool chamber is within the allowable operating depth range, that is, when the flow Qb of the steep slope fishway 63 is less than the allowable flow Qz of the main fishway, it can be ensured that the water depth of the main fishway 1 corresponding to the flow Qb is the optimal or allowable operating depth, and the outlet submerged depth of the steep slope fishway 63 is determined, and the outlet submerged depth meets the fish migration.

[0087] Step S4 is specifically as follows:

[0088] Step S41, determining the main fishway 1 with higher fish passing efficiency as having the best operating water depth range Hzx to Hzd through the efficiency relationship curve;

[0089] Step S42, determining the optimal operating water depth range Hjx-Hjd of the inlet of the steep slope fishway 63 with higher fish passing efficiency.

[0090] Specifically, the model test is used to check whether the water depth meets the connection with the inlet water level of the steep slope fishway 63 and the minimum submerged water depth Hjx requirements. If not, it means that the flow Qb discharged through the steep slope fishway 63 is insufficient at this time. The opening amplitude of the movable gate 5 is adjusted, and the auxiliary flow is adjusted to meet the minimum operating water depth Hzx requirement of the main fishway 1.

[0091] For example, see Table 2 for the hydraulic test results. Taking working condition 1 (minimum operating water depth of main fishway 1) as an example, the test results show that at this time, the Qb flow is small, the water depth of the main fishway 1 pool is low, and the water depth at the entrance of the steep slope fishway 63 is shallow, resulting in a significant head drop between the entrance of the steep slope fishway 63 and the pool of the main fishway 1, and the turbulence is relatively strong. The fish passing effect of this working condition test is poor (see Figure 6 ), the upstream passing rate of the steep slope fishway 63 is 43.75%. Directly opening the movable gate 5 to supplement the flow to the main fishway 1 increases the water depth of the main fishway 1 pool and the submerged water depth at the entrance of the steep slope fishway 63, thereby meeting the minimum submerged water depth Hjx requirement.

[0092] In order to eliminate the adverse effect of insufficient water depth at the inlet of the steep slope fishway 63, under the same initial operating conditions (i.e., the upstream water level is 214.70 m), the movable gate 5 (the gate opening is about 0.045 m) is opened to supplement the flow to the main fishway 1, so that the submerged water depth at the inlet of the steep slope fishway 63 rises to the optimal operating depth of 0.70 m. At this time, the flow is divided into two parts: the flow Qb of the steep slope fishway 63 and the flow Qa of the movable gate 5, which flow into the main fishway 1 together. See Table 3 for details.

[0093] (Table 3: Gate A water replenishment test conditions)

[0094]

[0095]

[0096] The final gate opening of 0.045m is based on the flooded orifice outflow formula in the calculation and analysis module, the water level difference △h obtained by the water level before and after the gate measured by the monitoring subsystem, and the steep slope fishway inlet flooding depth target determined by the expert decision subsystem. The required opening is gradually achieved according to the control process. The effect after adjustment is shown in Figure 7 .

[0097] Submerged orifice outflow formula

[0098] Where: Q is the flow rate, A is the submerged orifice area, μ is the flow coefficient, △h is the calculated water head, and g is the gravitational acceleration.

[0099] Step S5 is specifically as follows:

[0100] Step S51, determining the maximum operating water depth Hzd of the main fishway with high fish passing efficiency based on the water depth of the main fishway 1 and the passing efficiency relationship curve in step S41;

[0101] Step S52, verifying whether the maximum operating water depth range covers the requirement of the optimal maximum submerged water depth Hjd of the inlet of the steep slope fishway 63 by using the water depth of the main fishway 1 and the passing efficiency relationship curve in step S41, as well as the model test.

[0102] Specifically, from Figure 5 and Figure 6 It can be seen that the maximum operating water depth Hzd with high fish passing efficiency of the main fishway 1 is 1.10m, which covers the requirement that the optimal maximum submerged water depth Hjd of the inlet of the steep slope fishway 63 is 0.85;

[0103] Specifically, from Figure 5 and Figure 6 It can be seen that the model test verifies whether the optimal minimum submerged depth Hzx of the main fishway 1 meets the connection with the inlet water level of the steep slope fishway 63 and the minimum submerged depth Hjx. If not, it means that the flow discharged through the steep slope fishway 63 is insufficient, and the movable gate 5 needs to be opened to adjust the auxiliary flow to meet the above requirements. In summary, the existence of the movable gate 5 plays an auxiliary regulatory role in the balance regulation of the pool flow, and its application is relatively flexible.

[0104] Step S6 is specifically as follows:

[0105] Step S61, determining the allowable operating water depth Hzy of the main fishway 1 with higher fish passing efficiency based on the water depth of the main fishway 1 and the passing efficiency relationship curve in step S41;

[0106] Step S62, verifying whether the requirement of the maximum submerged water depth Hjd at the inlet of the steep slope fishway 63 is met by the water depth of the main fishway 1 and the passing efficiency relationship curve in step S41 and the model test.

[0107] from Figure 5 and Figure 6 It can be seen that the maximum operating water depth Hzd with higher fish passing efficiency of the main fishway 1 is 1.62m, which meets the requirement that the maximum submerged water depth Hjd of the inlet of the steep slope fishway 63 is 0.83.

[0108] Comprehensive analysis of the test:

[0109] In order to intuitively observe and judge the fish passing effect of the fishway at various upstream water levels, the upstream passing rate of the main fishway is combined with the upstream passing rate of the steep slope fishway to obtain the comprehensive upstream passing rate of the fishway using the fine control method.

[0110] (Table 4: Statistics of comprehensive passing rate of fishways in various working conditions)

[0111]

[0112] The results show that the comprehensive upstream pass rate of the fishway is determined by the upstream water level of the steep slope fishway 63. It shows a trend of increasing first and then decreasing with the change of water level, and the upstream pass rate reaches a maximum value of 71.09% at H = 214.91m. Flow regulation and control of the main fishway water depth (auxiliary regulation by movable gate 5 and main regulation by superimposed gate 6) under low water depth conditions can greatly improve the comprehensive upstream pass rate of the test fish.

[0113] Optimal operating water depth of main fishway 1 chamber Hz: It is divided into the optimal operating water depth (Hzx, Hzd) and the allowable operating water depth Hzy, which are determined by the relationship between the water depth of the main fishway chamber and the fish passage effect through biohydraulic model tests or prototype observations ( Figure 5 ); The optimal submerged water depth Hj at the inlet of the steep slope fishway 63 is further divided into the minimum submerged water depth Hjx and the maximum submerged water depth Hjd; The optimal submerged water depth Hc at the outlet of the steep slope fishway 63 is further divided into the minimum submerged water depth Hcx and the maximum submerged water depth Hcd.

[0114] The above orientation designations do not represent the specific orientations of the components in this implementation scheme. This implementation scheme is only for the convenience of describing the scheme, and the orientations are described relatively with reference to the figures. In essence, the specific orientations of the components are described according to their actual installation and actual use as well as the customary orientations of technicians in this field. This is hereby explained.

[0115] The specific implementation methods described above further describe the invention purpose, technical solutions, and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the protection scope of the present invention. It is particularly pointed out that for those skilled in the art, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for controlling the water depth of a fishway chamber, characterized in that: The invention comprises a main fishway (1), wherein a flow-isolating pier (2) is provided in the middle of the main fishway (1), and the upstream section of the main fishway (1) is divided into an A-zone channel (3) and a B-zone channel (4) by the flow-isolating pier (2); a movable gate (5) is provided on the upstream water inlet of the A-zone channel (3), and a superimposed gate (6) is provided on the upstream water inlet of the B-zone channel (4); the superimposed gate (6) is composed of a fixed section (61) at the bottom and a movable section (62) at the top; a steep slope fishway (63) is installed through the movable section (62) of the superimposed gate (6), and the other end of the steep slope fishway (63) enters the B-zone channel (4).

2. A design method for a device for controlling the water depth of a fishway chamber according to claim 1, characterized in that: The steps include: Step S1, determining the bottom elevation at the exit of the steep slope fishway (63) based on the lowest design water level upstream of the main fishway (1) and the minimum flooding depth at the exit of the steep slope fishway (63); Step S2, verifying that the vertical height of the baffle in the steep slope fishway (63) + the bottom elevation at the exit of the steep slope fishway (63) is greater than the highest design water level upstream of the main fishway (1) to ensure that the baffle in the steep slope fishway (63) is not submerged; Step S3, checking whether the flow rate Qb of the steep slope fishway (63) is less than the flow rate Qz of the main fishway (1), so as to ensure that the water depth of the main fishway (1) corresponding to the flow rate is within the optimal allowable operating depth range; Step S4, determining the fish passing efficiency based on the water depth of the main fishway (1); Step S5, verifying through a model test whether the optimal minimum flooding depth of the main fishway (1) meets the connection with the inlet water level of the steep slope fishway (63) and the requirements of the minimum flooding depth. If not, it means that the flow rate discharged through the steep slope fishway (63) is insufficient, and it is necessary to open the superimposed gate (6) to adjust the auxiliary flow rate to meet the requirements; Step S6, determining the maximum operating water depth range of the main fishway with high fish passing efficiency based on the water depth of the main fishway (1), and verifying through a model test whether the water depth meets the requirement of covering the optimal maximum submerged water depth of the entrance of the steep slope fishway (63); Step S7, determining the allowable operating water depth range of the main fishway (1) with higher fish passing efficiency based on the water depth of the main fishway (1), and verifying through a model test whether the water depth meets the requirement of the optimal maximum submerged water depth of the inlet of the steep slope fishway (63); Step S8, determine the operation scheduling mode; Step S9: Fix the determined operation procedure into the system.

3. The design method of the device for controlling the water depth of the fishway chamber according to claim 3, characterized in that: Step S1 is specifically as follows: Step S11, determining the optimal operating water depth of the main fishway (1) and the optimal submerged water depth of the inlet and outlet of the steep slope fishway (63); Step S12, carrying out model tests when the upstream main fishway (1) operates at the lowest water level of 214.70 m, and the upstream highest water levels of 214.82 m, 214.91 m, and 215.00 m in the upstream main fishway (1); Step S13, based on the design result of step S12, finely control the movable gate (5) and the overlapping gate (6), and finally determine the bottom elevation data at the exit of the steep slope fishway (63); Step S14, checking the bottom elevation result at the exit of the steep slope fishway (63) in step S13.

4. The method for designing a device for controlling the water depth of a fishway chamber according to claim 3, characterized in that: Step S2 is specifically as follows: Step S21, setting the vertical height of the inner baffle of the steep slope fishway (63); Step S22, the actual bottom elevation data of the steep slope fishway (63) is added to the vertical height of the baffle plate 0.93m to obtain the sum of the data; The sum of the data obtained in step S23 and step S22 is compared with the data of the bottom elevation at the exit of the steep slope fishway (63) obtained in step S13 to obtain a result. If the former is greater than the latter, the bottom elevation at the exit of the steep slope fishway (63) meets the design requirements.

5. The method for designing a device for controlling the water depth of a fishway chamber according to claim 3, characterized in that: Step S3 is specifically as follows: Step S31, determining the highest design water level upstream of the main fishway (1), and when the outlet of the steep slope fishway (63) is at the maximum flooding depth, checking whether the flow rate Qb of the steep slope fishway (63) is less than the flow rate Qz of the main fishway (1); Step S32: If the result obtained from step S31 is Qb>Qz, it means that it is necessary to adjust the bottom elevation of the superimposed gate (6) in the channel (4) of zone B to reduce the flooding depth of the outlet of the steep slope fishway (63) so that Qb≤Qz can meet the design requirements.

6. The method for designing a device for controlling the water depth of a fishway chamber as claimed in claim 3, characterized in that: Step S4 is specifically as follows: Step S41, determining the main fishway (1) with higher fish passing efficiency as the optimal operating water depth range through the efficiency relationship curve; Step S42, determining the optimal operating water depth range of the inlet of the steep slope fishway (63) with higher fish passing efficiency.

7. The method for designing a device for controlling the water depth of a fishway chamber as claimed in claim 3, characterized in that: Step S5 is specifically as follows: Step S51, determining the maximum operating water depth of the main fishway with high fish passing efficiency based on the water depth of the main fishway (1) and the passing efficiency relationship curve in step S41; Step S52, based on the water depth of the main fishway (1) and the passing efficiency relationship curve in step S41, as well as the model test, verify whether the maximum operating water depth range covers the optimal maximum submerged water depth of the inlet of the steep slope fishway (63).

8. The method for designing a device for controlling the water depth of a fishway chamber as claimed in claim 3, characterized in that: Step S6 is specifically as follows: Step S61, determining the allowable operating water depth of the main fishway with higher fish passing efficiency based on the water depth of the main fishway (1) and the passing efficiency relationship curve in step S41; Step S62: Check whether the water depth of the main fishway (1), the passing efficiency relationship curve in step S41 and the model test meet the requirements of the maximum submerged water depth of the steep slope fishway entrance.

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