Two-stage dispersion cascade ship lock water delivery arrangement and water storage channel water level control method

Abstract

The application relates to the field of ship lock navigation, and discloses a two-stage distributed cascade ship lock water delivery arrangement and water level control method of a storage channel, which comprises an open water-saving pool, a storage channel, a water supplement pool and a water overflow pool. The water head difference between the cascade water-saving pool and the lock chamber is used to control the water filling and discharging process, the ship lock operation water head is reduced, the storage channel is used for water storage and water delivery, the ship lock and the intermediate channel water head are reduced, the water body entering and leaving the intermediate channel is reduced, and the navigation water flow condition in the intermediate channel is ensured. The water supplement and overflow control of the storage channel is based on real-time water level monitoring. When the water level difference between the upstream and downstream and the intermediate channel is unbalanced, the water supplement pool and the water overflow pool are used for dynamic adjustment to keep the intermediate channel water level constant and ensure the safe navigation of ships. The application effectively reduces the ship lock operation water head, greatly reduces the water body entering and leaving the intermediate channel, has the water-saving function, realizes the efficient use of water resources, and is suitable for the cascade ship lock system with a large water head difference.

Description

Technical Field

[0001] This invention relates to the field of ship lock navigation technology, specifically to a two-stage decentralized cascade ship lock water conveyance arrangement and a water level control method for water storage channels. Background Technology

[0002] With the continuous expansion and deepening of the national waterway transportation network, especially in the cascade hydropower development process in basins such as the upper reaches of the Jinsha River, the construction of navigation capacity has increasingly become a key issue. Currently, on the Jinsha River, apart from the Xiangjiaba cascade which has been equipped with navigation structures to ensure smooth navigation, and the Xiluodu hub which has only reserved space for navigation facilities, most cascades have neither built nor reserved space for navigation facilities because navigation needs were not fully considered in the initial design. This has greatly limited the comprehensive utilization of regional water transport resources and the balanced development of the basin economy.

[0003] In response to this situation, one traditional solution is to directly modify the floodgate, sacrificing some flood discharge function to construct navigation facilities. However, this solution not only affects the stability and safety of the dam's main structure, but its applicability is also limited to concrete gravity dams with relatively thick dam bodies. For arch dams with more delicate structures and relatively thinner dam bodies, the implementation risk increases significantly and may endanger the overall safety of the dam.

[0004] To overcome the aforementioned limitations, the industry has explored another innovative approach—combining navigation structures with intermediate channels (long-distance tunnels). This approach, through flexible spatial layout, allows navigation facilities to be built away from the dam site, effectively avoiding direct interference with the main dam structure and ensuring dam safety, as seen in the Three Gorges New Channel. However, the decentralized two-stage ship lock water conveyance scheme presents several challenges:

[0005] (1) During the first-stage lock discharge process, if the lock water is discharged into the intermediate channel, the large discharge flow will worsen the water flow conditions in the intermediate channel, causing the flow velocity and fluctuation in the intermediate channel to exceed the standard. At the same time, the direct entry of a large volume of water into the intermediate channel will also cause the water level fluctuation in the intermediate channel to be too large. When the intermediate channel of the two-stage lock is a tunnel, in order to meet the navigation clearance requirements, the parameters such as the ship clearance height, ship draft, the excess water depth in the intermediate channel and the water level rise in the intermediate channel together determine the size of the tunnel. When the water level rise is too large, it will cause the tunnel construction cost to be too high and the construction difficulty to be too great.

[0006] (2) During the discharge process of the first-stage lock, if the lock water is directly discharged into the downstream river channel, the lock head will be too high. This high head will cause a series of problems associated with high-head locks, such as valve cavitation vibration, investment costs due to the complex layout of the water conveyance system, and water hammer when the lock needs to be opened and closed quickly in emergency situations. The highest head lock currently built is the Datengxia Lock, with a head of 40.25m. There is no practical engineering experience to guide locks with heads exceeding this, and there is no technical guarantee. At the same time, directly discharging the lock water into the downstream river channel will result in a large amount of water consumption, which is inconsistent with the low-carbon and environmentally friendly concept proposed by today's society.

[0007] (3) During the second-stage lock filling process, if the lock directly draws water from the middle channel, it will also cause problems such as deterioration of the water flow conditions in the middle channel and excessive fluctuation of the water level in the middle channel, and may also cause the ship to hit the bottom and cause safety problems.

[0008] (4) During the second-stage lock filling process, if the lock directly draws water from the upstream reservoir area, corresponding to (2), it will lead to problems such as excessively high water head and large water consumption during the lock filling process.

[0009] (5) Due to the water level changes upstream and downstream of the hub, when the amount of water discharged from the first-stage lock into the intermediate channel is not equal to the amount of water taken from the intermediate channel by the second-stage lock, there will be an impact on the accumulated water level in the intermediate channel, which may cause the ship to hit the bottom or have insufficient clearance. When the water discharge and water intake of the lock are not related to the intermediate channel, the water in the intermediate channel will be stagnant for a long time, which will lead to the deterioration of the water ecological environment in the intermediate channel.

[0010] Therefore, there is an urgent need for a water conveyance solution to address the difficulties in water conveyance from the decentralized two-stage ship lock. Summary of the Invention

[0011] To address the shortcomings of existing technologies, this invention provides a two-stage decentralized cascade lock water conveyance layout and water level control method for water storage channels. In a two-stage decentralized cascade lock system, the operating head is reduced and water level fluctuations are minimized, thereby achieving efficient utilization of water resources and stable control of the water level in the intermediate channels.

[0012] To achieve the above objectives, the present invention provides the following technical solution: a two-stage decentralized cascade lock water conveyance system, comprising a first-stage lock connecting an upstream reservoir, a second-stage lock connecting a downstream river channel, and an intermediate channel connecting the first-stage lock and the second-stage lock, characterized in that the water conveyance arrangement includes:

[0013] Water-saving pools are set up next to the first-stage lock and the second-stage lock respectively to reduce the operating head of the lock and to save water during lock operation.

[0014] The water storage channel located next to the intermediate channel is used to reduce the water head between the lock and the intermediate channel, as well as the water volume entering and leaving the intermediate channel from the lock, and to make the water head between the lock and the intermediate channel consistent, so as to keep the water level in the intermediate channel constant.

[0015] The replenishment pool and overflow pool, which are connected to the water storage channel, are used to regulate the water level in the water storage channel;

[0016] Water level sensors installed at the bottom of water storage channels, replenishment pools, and overflow pools are used to monitor water levels in real time.

[0017] The corridor at the bottom of the water storage channel is used for flow control of water between the water storage channel, the replenishment pool and the overflow pool.

[0018] Preferably, the areas of the replenishment tank and the overflow tank meet the water volume requirements under different extreme water level conditions:

[0019] Water replenishment pool area A bs Satisfying the formula:

[0020]

[0021] Among them, A c H is the cross-sectional area of ​​the water storage channel. ss H represents the water level in the lock chamber after the first-stage lock discharges water into the energy-saving pool. sx H represents the water level in the lock chamber after the second-stage lock's water-saving pool has filled the lock chamber. z For the water level in the intermediate channel, H umin denoted as the lowest navigable water level upstream, and x as the initial water level of the water storage channel;

[0022] Overflow pool area A ys Satisfying the formula:

[0023]

[0024] Where y is the water level in the storage channel after the gate chamber discharges water into the storage channel, and H is the water level in the storage channel. dmax This is the highest navigable water level downstream.

[0025] Preferably, two water level sensors are respectively arranged at the bottom of the water replenishment tank and the overflow tank to measure the real-time water level of the water replenishment tank and the overflow tank.

[0026] Preferably, the water level sensor in the water storage channel is installed at the bottom of the water storage channel and multiple sensors are arranged longitudinally along the channel to measure the average water level in the water storage channel.

[0027] This invention also provides a method for controlling the water level of a storage channel in a two-stage decentralized cascade ship lock, comprising the following steps:

[0028] Calculate the initial target water level of the water storage channel, and determine the target water level based on the water level difference between the upstream and downstream areas;

[0029] Use water level sensors to monitor the current water level in the water storage channel in real time and compare the current water level with the target water level;

[0030] When the current water level is higher than the target water level, the overflow tank will be activated to discharge excess water downstream.

[0031] When the current water level is lower than the target water level, the water replenishment pool is activated to replenish water from upstream to the water storage channel.

[0032] Preferably, the step of calculating the initial target water level of the water storage channel includes:

[0033] When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is equal to the head of the intermediate channel, the formula is satisfied:

[0034] H ss -H z =H z -H sx

[0035] The water storage channel is in a balanced state of neither replenishment nor overflow;

[0036] When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is greater than the head of the intermediate channel, the formula is satisfied:

[0037] H ss -H z >H z -H sx

[0038] The overflow volume is determined as follows:

[0039] A c (H ss +H sx -2H z )

[0040] When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is less than the head of the intermediate channel, the formula is satisfied:

[0041] H ss -H z <H z -H sx

[0042] The determined water replenishment amount is:

[0043] A c (H ss +H sx -2H z )

[0044] Among them, H ssH represents the water level in the lock chamber after the first-stage lock discharges water into the energy-saving pool. z For the water level in the intermediate channel, H sx A represents the water level in the lock chamber after the second-stage lock's water-saving pool has been filled with water. c This refers to the cross-sectional area of ​​the water storage channel.

[0045] Preferably, the water replenishment operation includes the following steps:

[0046] Calculate the difference between the initial water level and the current water level, and multiply it by the area A of the water storage channel. c To obtain the required amount of water;

[0047] Determine the required water level to be lowered in the water supply tank based on the amount of water to be supplied, and then open the drain valve of the water supply tank.

[0048] When the water level in the replenishment tank drops to the calculated value, close the drain valve of the replenishment tank.

[0049] Preferably, the overflow operation includes the following steps:

[0050] Calculate the difference between the initial water level and the current water level, and multiply it by the area A of the water storage channel. c To obtain the overflow volume;

[0051] Determine the required water level to be raised in the overflow tank based on the overflow volume, and then open the overflow tank filling valve.

[0052] When the water level in the overflow tank reaches the calculated value, close the overflow tank filling valve.

[0053] Preferably, during the water replenishment and overflow operations, the average value of the water level sensors of the three water storage channels is used as the real-time water level of the water storage channels to reduce the impact of water level fluctuations.

[0054] This invention provides a two-stage decentralized cascade ship lock water conveyance layout and a water level control method for water storage channels.

[0055] It has the following beneficial effects:

[0056] 1. This invention reduces the amount of water directly discharged into the downstream river channel during the operation of traditional locks by designing the layout of water-saving pools and water storage channels, realizes the reuse of lock water resources, significantly reduces overall water consumption, and meets the requirements of water conservation and environmental protection.

[0057] 2. This invention maintains a stable water level in the intermediate channel through precise control of the replenishment pool and the overflow pool, avoiding the impact of water level fluctuations on ship navigation, ensuring safe passage of ships, and improving navigation efficiency.

[0058] 3. This invention designs a water level control system for water storage channels. By setting the head difference and area ratio, the system can cope with different upstream and downstream water level changes and ensure stable water level regulation under various water level conditions.

[0059] 4. This invention can effectively reduce the operating head of the lock, reduce the impact of water flow on the lock and water-saving pool structure, extend the service life of the structure, and improve the safety and stability of operation.

[0060] 5. This invention reduces the operating head of the lock to a minimum through the synergistic effect of the water-saving pool and the water storage channel, avoiding water flow vibration and cavitation caused by high water head, and ensuring the safety and durability of the lock structure.

[0061] 6. The filling and emptying process of the lock and the intermediate channel allows for the natural replacement of water in the intermediate channel, which plays a positive role in improving the water quality of the intermediate channel and maintaining the ecological environment. Attached Figure Description

[0062] Figure 1 This is a schematic diagram of the layout of the two-stage decentralized cascade ship lock water conveyance system of the present invention;

[0063] Figure 2 In this embodiment of the invention, the head of the gate chamber to the water storage channel varies with m and k. c Diagram illustrating the relationship of change;

[0064] Figure 3 In this embodiment of the invention, the head of the gate chamber to the intermediate channel varies with m and k. c Diagram illustrating the relationship of change;

[0065] Figure 4 The water-saving rate of this embodiment of the invention varies with m and k. c Diagram illustrating the relationship of change. Detailed Implementation

[0066] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] Please see the appendix Figure 1 This invention provides a two-stage decentralized cascade lock water conveyance system, designed as a "water-saving pool + water storage channel" structure, specifically comprising:

[0068] Water-saving pool: Located next to the first and second stage locks, it reduces the water head of the locks while saving water during lock operation.

[0069] Water storage channel: Arranged parallel to the middle channel, it reduces the water head between the lock and the middle channel, as well as the water volume entering and leaving the middle channel from the lock, and ensures that the water head between the lock and the middle channel is consistent, so that the water level in the middle channel remains constant.

[0070] Water replenishment pool and overflow pool: Located upstream and downstream of the water storage channel, they are used to regulate the water level of the water storage channel. When the water level of the water storage channel is low, the water replenishment pool provides supplementary water. When the water level is high, the overflow pool discharges excess water.

[0071] like Figure 1 As shown, the unidirectional operation process of the water conveyance system of the two-stage decentralized cascade ship lock of the present invention is as follows:

[0072] When the first-stage lock is filled with water, the water-saving pool first fills the lock chamber, and then the upstream reservoir fills the lock chamber. (See...) Figure 1 The corresponding processes 1 and 2 in the text;

[0073] When the first-stage lock releases water, it first releases water into the water-saving pool, then into the storage channel, and finally into the intermediate channel. (See...) Figure 1 Processes 3, 4, and 5;

[0074] When filling the second-stage lock, the water-saving pool first fills the lock chamber, then the storage channel fills the lock chamber, and finally the intermediate channel fills the lock chamber. (See below) Figure 1 Processes 6, 7, and 8;

[0075] When the second-stage lock releases water, it first releases water into the water-saving reservoir, and then releases water into the downstream channel. Figure 1 Processes 9 and 10.

[0076] This invention ingeniously combines reducing the operating head of the lock with minimizing the water volume in the intermediate channel. Through a water-saving pool and storage channel, it not only significantly reduces the operating head of the lock but also effectively controls the amount of water entering the intermediate channel. Simultaneously, this scheme ensures a dynamic balance between water discharge and intake in the intermediate channel, maintaining a stable water level and providing strong protection for the safe passage of ships. Furthermore, the filling and emptying process of the lock and intermediate channel promotes the natural replacement of water within the intermediate channel, playing a positive role in improving water quality and maintaining the ecological environment.

[0077] 1. This invention provides a theoretical framework for the layout of a water-saving tank + water storage channel water conveyance system, as detailed below:

[0078] (1) Theory of Water Storage Channel Layout

[0079] To ensure water level balance between the water-saving pool and the lock chamber during water-saving operation of the lock, the water-saving pool is designed as an open structure with an area ratio of k to the lock chamber. c Assume the number of stages in the water-saving reservoir is m, and the water level downstream of the first-stage lock is the water level H in the intermediate channel. zThe water level upstream of the second-stage lock is the same as the water level in the middle channel, H. z The water level downstream of the second-stage lock is the downstream river level H. d .

[0080] After the first-stage lock discharges water into the water-saving pool, the water level in the lock chamber is recorded as H. ss The calculation formula is:

[0081]

[0082] After the second-stage lock's sludge basin fills the lock chamber with water, the water level in the lock chamber is recorded as H. sx The calculation formula is:

[0083]

[0084] Assuming the initial water level in the storage channel is x, after the first-stage lock chamber discharges water into the storage channel, the water level in the storage channel will rise by a value Δh1, calculated as follows:

[0085]

[0086] Among them, A c Let A be the area of ​​the gate chamber. cs This refers to the area of ​​the water storage channel.

[0087] When water is discharged from the storage channel into the second-stage lock, the water level in the storage channel will decrease by a value Δh2, calculated as follows:

[0088]

[0089] To ensure that the amount of water discharged from the lock into the intermediate channel is equal to the amount of water drawn from the intermediate channel, and to maintain a constant water level in the intermediate channel after one cycle, the following relationship must be satisfied:

[0090]

[0091] Among them, H z This refers to the water level in the intermediate channel.

[0092] Let y be the water level in the storage channel after the gate chamber discharges water into the storage channel, that is:

[0093] y=x+Δh1 (6)

[0094] From (4), (5), and (6), we can obtain:

[0095]

[0096] Calculated through (7):

[0097]

[0098] From (3), (6), and (8), we can obtain:

[0099]

[0100] Substituting (8) into (9) yields:

[0101]

[0102] (2) Theory of Water Level Control and Overflow Water Replenishment in Water Storage Channels

[0103] To maintain dynamic water level balance in the intermediate channel and ensure that the discharge and intake of the lock are equal, water replenishment or overflow operations are required to control the initial water depth of the storage channel. The water level control replenishment / overflow theory for the storage channel is as follows:

[0104] When the water level in the storage channel returns to its initial value after operation, there is no need to replenish or overflow water, i.e., y-Δh2=x;

[0105] When the water level in the storage channel is higher than the initial value, an overflow operation is required, and the overflow volume is:

[0106] A cs (y-Δh2-x)

[0107] When the water level in the storage channel is lower than the initial value, water replenishment is required. The amount of water to be replenished is:

[0108] A cs (x-(y-Δh2))

[0109] If the water head of the first-stage lock and the second-stage lock are equal at the intermediate channel, the overflow operation volume can be further simplified to the following formula:

[0110] When H ss -H z =H z -H sx At this time, the water storage channel does not need to be replenished with overflow water;

[0111] When H ss -H z >H z -H sx At that time, the water storage channel overflowed, and the overflow volume was:

[0112] A c (H ss +H sx -2H z (11)

[0113] When H ss -H z <H z -H sxAt that time, water is replenished to the water storage channel, and the replenishment amount is:

[0114] A c (H ss +H sx -2H z (12)

[0115] 2. This invention provides the water level changes and the arrangement of operating head and elevation during the operation of a ship lock.

[0116] (1) The first-stage lock was filled with water.

[0117] During the filling of the first-stage lock:

[0118] Initially, the water level in the gate chamber is equal to the water level in the intermediate channel, H. z The upstream reservoir water level is H. u .

[0119] The initial water level H of the i-th level water-saving pool 1cs (i) The calculation is as follows:

[0120]

[0121] After the i-th stage water-saving pool fills the gate chamber with water, the water levels in the water-saving pool and the gate chamber are:

[0122]

[0123] The head of provincial water tanks and sluice chambers at all levels is as follows:

[0124]

[0125] After the provincial water reservoir is put into operation, the upstream reservoir fills the sluice chamber with water. The water head between the sluice chamber and the upstream reservoir is:

[0126]

[0127] The water level in the sluice chamber rose to the upstream water level H. u The first-stage lock has been filled with water.

[0128] (2) First-stage lock water discharge

[0129] Before the first-stage lock discharges water, the initial water level in the lock chamber is H, which is the upstream reservoir water level. u Then the initial water level of the i-th level water-saving pool is the water level after the previous water-saving pool filled the gate chamber, that is:

[0130]

[0131] The head of the gate chamber and the water-saving pool is:

[0132]

[0133] After the first-stage gate chamber discharges water into the i-th-stage water-saving pool, the water levels in the water-saving pool and the gate chamber are:

[0134]

[0135] Water is discharged from the first-stage lock into the storage channel. The initial water level in the storage channel is:

[0136] H cs =x (20)

[0137] The water head of the water storage channel and the gate chamber is:

[0138]

[0139] After the gate chamber is emptied, the water level in the gate chamber and the water level in the storage channel are as follows:

[0140]

[0141] Where, H cs This represents the initial water level in the water storage channel.

[0142] The first-stage lock discharges water into the intermediate channel. The water head in the intermediate channel and the lock chamber is:

[0143] d xcz =H′ 1xcs -H z (twenty three)

[0144] After the gate chamber discharges water into the intermediate channel, the water levels in the gate chamber and the intermediate channel are as follows:

[0145]

[0146] (3) The second-stage lock was filled with water.

[0147] Before the second-stage lock is filled with water, the initial water level in the lock chamber is the downstream river level H. d The upstream water level of the sluice chamber is the same as the previous discharge level of the intermediate channel, H. 1xz Then the initial water level of the i-th level water-saving pool is:

[0148]

[0149] After the i-th stage water-saving pool fills the gate chamber with water, the water levels in the water-saving pool and the gate chamber are:

[0150]

[0151] The head of provincial water tanks and sluice gates at all levels is

[0152]

[0153] Before the water is filled into the second-stage lock, the initial water level in the water storage channel is H′. 1xcsThe water head of the water storage channel and the gate chamber is:

[0154]

[0155] After the water storage channel is filled with water into the second-stage lock, the water levels in the water storage channel and the lock chamber become:

[0156]

[0157] The head of the gate chamber and the intermediate channel is:

[0158] d 2czz =H 1xz -H 2ccs (30)

[0159] Water is pumped into the sluice chamber through the intermediate channel. The water levels in the sluice chamber and the intermediate channel are as follows:

[0160]

[0161] (4) Second-stage lock water release

[0162] Before the second-stage lock discharges water, the initial water level in the lock chamber is the intermediate channel water level H. 2cz The downstream river level is H. u Then the initial water level of the i-th level water-saving pool is the water level after the previous water-saving pool filled the gate chamber, that is:

[0163]

[0164] The head of the gate chamber and the water-saving pool is:

[0165]

[0166] After the first-stage gate chamber discharges water into the i-th-stage water-saving pool, the water levels in the water-saving pool and the gate chamber are:

[0167]

[0168] The second-stage lock discharges water into the downstream channel. The water head between the lock chamber and the downstream channel is:

[0169] d xzd =H′ 2xs (m)-H d (35)

[0170] The water level in the sluice chamber will reach the downstream water level H. d .

[0171] Based on the above water levels, the extreme operating condition combination can be calculated as follows:

[0172] (1) The highest water level upstream H umax ~Lowest water level H dmin ;

[0173] (2) The highest water level upstream H umax ~Highest downstream water level H dmax ,

[0174] (3) Lowest water level upstream H umin ~Lowest water level H dmin ,

[0175] (4) Lowest water level upstream H umin ~Highest water level downstream H dmax .

[0176] To obtain the lowest water level of the water-saving pool, the highest water level of the water-saving pool, the lowest water level of the water storage channel, and the highest water level of the water storage channel under four extreme water levels, based on experience, the bottom elevation of the water-saving pool should be at least 1m lower than the lowest water level of the water-saving pool, the top elevation of the water-saving pool should be at least 2m higher than the water level of the water-saving pool, the bottom elevation of the water storage channel should be at least 2m lower than the lowest water level of the water storage channel, and the top elevation of the water storage channel should be at least 4m higher than the highest water level of the water storage channel.

[0177] 3. This invention provides a theory for calculating water-saving rates.

[0178] A combined navigation structure consisting of two-stage ship locks and an intermediate channel, where the locks do not employ water-saving measures (i.e., the water discharged from the first and second stage locks is directly discharged into the downstream river channel), consumes a water volume V. h for:

[0179] V h =(H u -H z A c +(H z -H d )*A c =(H u -H d A c (36)

[0180] When the "water-saving pool + water storage channel" scheme is implemented, its one-cycle process involves filling the first-stage lock with water, emptying the first-stage lock with water, filling the second-stage lock with water, and emptying the second-stage lock with water. The water consumption V in this process is... s The amount of water V discharged into the downstream approach channel from the second-stage ship lock x The volume of water V discharged into the downstream river channel via the first-stage lock through overflow is... y The sum is:

[0181] V s =V x +V y (37)

[0182]

[0183] Where H ss -H z >H z -H sx hour,

[0184] V y =A c (H ss +H sx -2H z (39)

[0185] When H ss -H z <H z -H sx hour,

[0186] V y =0 (40)

[0187] The water saving rate ssl is:

[0188]

[0189] 4. This invention provides a method for precise water level control in water storage channels and an arrangement of overflow tanks.

[0190] To achieve dynamic equilibrium of the water in the intermediate channel, the amount of water discharged from the lock should be equal to the amount of water taken from the lock. When the difference between the water level upstream and downstream and the water level in the intermediate channel is not equal, it is necessary to carry out overflow operation. The method of controlling the water level in the intermediate channel in this plan is to control the initial water depth of the water storage channel.

[0191] According to the theory of water level control and overflow in water storage channels, when H ss -H z =H z -H sx The water storage channel will not overflow without being replenished, when H ss -H z >H z -H sx The water storage channel overflowed, and the overflow volume was A. c (H ss +H sx -2H z ); when H ss -H z <H z -H sx Water is being replenished to the water storage channel, with a replenishment volume of A. c (H ss +H sx -2H z ).

[0192] However, there are two problems with precisely controlling water storage channels:

[0193] (1) The water storage channel has a large area, and when using traditional sensors to measure water level, the sensor measurement accuracy is required to be high.

[0194] (2) When adjusting the water level of the water storage channel, water is added to or drained into the water storage channel. However, due to the fluctuation of the water surface in the water storage channel during the filling or draining process, it is difficult to accurately measure the real-time water level in the water storage channel to determine the timing of valve closure. If the valve is not closed in time, the water level in the water storage channel will be significantly different from the initial water level.

[0195] Therefore, a water replenishment pool is arranged upstream of the water storage channel, and an overflow pool is arranged downstream. The areas of the water replenishment pool and the overflow pool are kept as small as possible to reduce the high-precision requirements of the sensor measurements. Meanwhile, the area A of the water replenishment pool... bs The overflow pool must be able to replenish the required water volume of the storage channel in one go when the upstream water level is at its lowest navigable level. The overflow pool area is A. ys It must be able to discharge excess water in one go at the highest navigable water level downstream, i.e.:

[0196]

[0197] Among them, H umin H is the lowest navigable water level upstream. dmax This is the highest navigable water level downstream.

[0198] The corresponding water storage channel overflow replenishment operation is as follows:

[0199] (1) Install three water level sensors below the lowest water level in the water storage channel;

[0200] (2) Install two water level sensors below the lowest water level in the water replenishment tank.

[0201] Before the lock is put into operation, the initial water level that needs to be set in the water storage channel is calculated based on the upstream and downstream water levels. The average value of the three sensor values ​​in the water storage channel is taken as the water level in the water storage channel and compared with the current measured water level.

[0202] 1) If the initial water level is higher than the current measured water level, water replenishment is required.

[0203] The replenishment volume can be obtained by multiplying the difference between the initial and current water levels by the area of ​​the storage channel. Dividing the replenishment volume by the area of ​​the replenishment pool yields the required water level drop. First, open the replenishment pool's filling valve. Once the water level in the replenishment pool is level with the upstream water level, close the valve. Then, open the replenishment pool's drain valve. Water flows through the replenishment pool's drain corridor into the bottom corridor of the storage channel and into the storage channel through five sections of top support holes. When the water level drop in the replenishment pool equals the calculated required water level drop, close the replenishment pool's drain valve.

[0204] 2) If the initial water level is lower than the current measured water level, an overflow operation is required.

[0205] The overflow volume can be obtained by multiplying the difference between the initial and current water levels by the area of ​​the storage channel. Dividing the overflow volume by the overflow pool area yields the required water level drop in the overflow pool. First, open the overflow pool's drain valve. Once the overflow pool level is equal to the downstream water level, close the drain valve. Then, open the overflow pool's filling valve. Water enters the storage channel's bottom corridor through the top support hole in section 5 and flows into the overflow pool through the top support hole. When the overflow pool's rising water level equals the calculated required rising water level, close the overflow pool's filling valve.

[0206] The above arrangement ensures a smooth transition during the filling and emptying of the lock and water storage channels. Water level control in the tiered water-saving pools and water level regulation in the storage channels prevent the impact of water flow on the facility structure. Under extreme water level conditions, the replenishment and overflow pools provide dynamic balancing support, and the elevation design of the water-saving pools and storage channels ensures the safety and continuous stable operation of the system.

[0207] To better understand the present invention, the above method will be described in detail below with reference to specific embodiments.

[0208] Example:

[0209] Taking a specific engineering project as an example, a "water-saving reservoir + water storage channel" layout is implemented. The highest navigable water level upstream is 293m, and the lowest is 278m. Downstream, the highest navigable water level is 227m, and the lowest is 211.4m. Since the upstream and downstream water level variations are similar, the lock head is divided using a bi-directional head allocation method, resulting in a total head of 81.6m, a single-stage lock head of 40.8m, and an intermediate channel head of 252.2m. The two lock stages are connected by a bi-directional long-distance tunnel forming an intermediate channel with an area of ​​approximately 112,586 m². 2 The water storage channel and the intermediate channel are arranged in parallel, with a total area of ​​26,962 square meters and a gate chamber area of ​​5,222 square meters. 2 To meet the navigation flow conditions within long-distance tunnels, the water discharged into the intermediate channel shall not exceed 2.5m of the gate chamber area.

[0210] (1) The number of stages m and the area k of the provincial water tank c Sure

[0211] The maximum water head during lock operation occurs during the water conveyance process between the storage channel and the lock chamber, determining the safety of the lock valves. The water head in the intermediate channel determines the flow conditions in the intermediate channel. Figures 2-4 It can be seen that as m and k c As the water level increases, the maximum head and the head from the lock chamber to the intermediate channel gradually decrease during lock operation, resulting in a gradual increase in water saving rate. However, the magnitude of the increase or decrease also varies with m and k. c The increase of k gradually decreases, that is, when m>3, k cAfter >2, increasing the number of water-saving tank stages and the area of ​​the water-saving tank has no significant effect on reducing the water head.

[0212] Meanwhile, to ensure efficient operation of the lock, the lock's operating time increases with the number of water-saving tank stages. Therefore, it is necessary to reduce the number of water-saving tank stages when m and k... c When the value equals 0, it means the lock is not operating in a water-saving manner, and the head from the lock chamber to the intermediate channel reaches 44.4m, exceeding the 40.25m head of the Datengxia Lock, currently the largest single-stage lock with the highest head. When a first-stage water-saving pool (k) is used... c When k = 1, the maximum head decreases to 29.6m, but is still close to the 30m head. When using a Class 1 water-saving tank k... c When the maximum head is 2, the maximum head decreases to 26.6m. Considering the safety of lock operation, water conveyance time, engineering topography, water saving rate and investment, the project plans to adopt a Class 1 water-saving pool, with an area twice the area of ​​the lock chamber.

[0213] (2) Determination of the elevation of the provincial water tank and water storage channel

[0214] After determining the number and area of ​​the water-saving pool, the next step is to determine the elevation of the water-saving pool and the water storage channel. By calculating the water level of each part of the lock under extreme water level combination conditions, and arranging the elevation according to the principle that the water-saving pool has a surplus water depth of not less than 1m and the water storage channel has a surplus water depth of not less than 1.5m, the operating water level, water depth, water head and other data under each condition are shown in Tables 1 to 4.

[0215] Table 1. Water level changes during the water transfer process (293–211.4 m)

[0216]

[0217] Table 2. Water level changes during the water transfer process (278–211.4 m)

[0218]

[0219] Table 3. Water level changes during the water transfer process (293–227 m)

[0220]

[0221] Table 4. Water level changes during the water transfer process (278–227 m)

[0222]

[0223] (3) Determination of the overflow tank

[0224] The overflow tank directly replenishes or drains water from the storage channel, adjusting the initial water level of the channel. According to formulas (42) and (43), the maximum replenishment volume is 47,000 m³. 3 (Water level combination of 278-211.4m), maximum overflow is 48,900 m³.3 (Water level combination of 293-227m). To meet the overflow water demand, the overflow tank area is set at 2500m². 2 The bottom elevation of the water replenishment pool must be lower than 259.2 m, so we take 254 m; the bottom elevation of the overflow pool must be lower than 229.44 m, so we take 206.7 m.

[0225] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A two-stage decentralized cascade ship lock water conveyance system, characterized in that, The system includes a first-stage lock connecting an upstream reservoir, a second-stage lock connecting a downstream river channel, and an intermediate channel connecting the first-stage and second-stage locks. The water conveyance arrangement comprises: Water-saving pools are set up next to the first-stage lock and the second-stage lock respectively to reduce the operating head of the lock and to save water during lock operation. The water storage channel located next to the intermediate channel is used to reduce the water head between the lock and the intermediate channel, as well as the water volume entering and leaving the intermediate channel from the lock, and to make the water head between the lock and the intermediate channel consistent, so as to keep the water level in the intermediate channel constant. The replenishment pool and overflow pool, which are connected to the water storage channel, are used to regulate the water level in the water storage channel; Water level sensors installed at the bottom of water storage channels, replenishment pools, and overflow pools are used to monitor water levels in real time. The corridor at the bottom of the water storage channel is used for flow control of water between the water storage channel, the water replenishment pool and the overflow pool; The areas of the replenishment and overflow tanks are sufficient to meet the water volume requirements under different extreme water level conditions: Water replenishment pool area Satisfying the formula: in, This refers to the cross-sectional area of ​​the water storage channel. The water level in the lock chamber after the first-stage lock discharges water into the water-saving pool. The water level in the lock chamber after the second-stage lock's water-saving pool has been filled with water. The water level in the middle channel. This is the lowest navigable water level upstream. This represents the initial water level in the water storage channel; overflow pool area Satisfying the formula: in, This refers to the water level in the storage channel after water is discharged from the sluice chamber into the storage channel. This is the highest navigable water level downstream.

2. The two-stage decentralized cascade ship lock water conveyance system according to claim 1, characterized in that, Two water level sensors are respectively installed at the bottom of the water replenishment pool and the overflow pool to measure the real-time water level of the water replenishment pool and the overflow pool.

3. The two-stage decentralized cascade ship lock water conveyance system according to claim 1, characterized in that, The water level sensor in the water storage channel is installed at the bottom of the channel and multiple sensors are arranged longitudinally along the channel to measure the average water level in the water storage channel.

4. A method for controlling the water level of a storage channel in a two-stage decentralized cascade ship lock, based on the two-stage decentralized cascade ship lock water conveyance system as described in any one of claims 1-3, characterized in that, Includes the following steps: Calculate the initial target water level of the water storage channel, and determine the target water level based on the water level difference between the upstream and downstream areas; Use water level sensors to monitor the current water level in the water storage channel in real time and compare the current water level with the target water level; When the current water level is higher than the target water level, the overflow tank will be activated to discharge excess water downstream. When the current water level is lower than the target water level, the water replenishment pool is activated to replenish water from upstream to the water storage channel.

5. The method for controlling the water level of the storage channel in a two-stage decentralized cascade ship lock according to claim 4, characterized in that, The steps for calculating the initial target water level of the water storage channel include: When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is equal to the head of the intermediate channel, the formula is satisfied: The water storage channel is in a balanced state of neither replenishment nor overflow; When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is greater than the head of the intermediate channel, the formula is satisfied: The overflow volume is determined as follows: When the head of the lock chamber after the first-stage lock discharges water into the water-saving pool is less than the head of the intermediate channel, the formula is satisfied: The determined water replenishment amount is: in, The water level in the lock chamber after the first-stage lock discharges water into the water-saving pool. The water level in the middle channel. The water level in the lock chamber after the second-stage lock's water-saving pool has been filled with water. This refers to the cross-sectional area of ​​the water storage channel.

6. The method for controlling the water level of the storage channel in a two-stage decentralized cascade ship lock according to claim 4, characterized in that, The water replenishment process for the replenishment tank includes the following steps: Calculate the difference between the initial water level and the current water level, and multiply it by the area of ​​the water storage channel. To obtain the required amount of water; Determine the required water level to be lowered in the water supply tank based on the amount of water to be supplied, and then open the drain valve of the water supply tank. When the water level in the replenishment tank drops to the calculated value, close the drain valve of the replenishment tank.

7. The method for controlling the water level of the storage channel in a two-stage decentralized cascade ship lock according to claim 4, characterized in that, The process of draining water from the overflow tank includes the following steps: Calculate the difference between the initial water level and the current water level, and multiply it by the area of ​​the water storage channel. To obtain the overflow volume; Determine the required water level to be raised in the overflow tank based on the overflow volume, and then open the overflow tank filling valve. When the water level in the overflow tank reaches the calculated value, close the overflow tank filling valve.

8. The method for controlling the water level of the storage channel in a two-stage decentralized cascade ship lock according to claim 4, characterized in that, During the replenishment of the water tank and the discharge of the overflow tank, the average value of the water level sensors of the three water storage channels is used as the real-time water level of the water storage channels to reduce the impact of water level fluctuations.

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