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

Abstract

The invention relates to the field of ship lock navigation, and discloses a two-stage dispersed stepped ship lock water delivery arrangement and water storage channel water level control method, which comprises an open type water-saving pool, a water storage channel, a water supplementing pool and an overflow pool, and is characterized in that the water filling and drainage process is controlled through the water head difference between the graded water-saving pool and a lock chamber, and the ship lock operation water head is reduced; the water storage channel is used for storing and transporting water, water heads of the ship lock and the middle channel are lowered, water entering and exiting from the middle channel are reduced, and navigation water flow conditions in the middle channel are guaranteed; water supplementing and overflowing control of the water storage channel is based on real-time water level monitoring, and when the upstream and downstream water levels and the water level of the middle channel are not balanced, dynamic adjustment is conducted through the water supplementing pool and the overflowing pool to keep the water level of the middle channel constant, and safe passing of ships is guaranteed. The cascade ship lock effectively reduces the running water head of the ship lock, greatly reduces water entering and exiting from a middle channel, has a water-saving function, realizes efficient utilization of water resources, and is suitable for a cascade ship lock system with a large water head difference.

Description

Technical Field

[0001] The invention relates to the technical field of ship lock navigation, and in particular to a two-stage dispersed cascade ship lock water delivery arrangement and a water storage channel water level control method. Background Art

[0002] With the continuous expansion and deepening of the national water transport network, especially in the process of cascade hydropower development in river basins such as the upper reaches of the Jinsha River, the construction of navigation capacity has become an increasingly key issue. At present, except for the Xiangjiaba cascade on the Jinsha River, which has been equipped with navigation buildings to ensure smooth navigation, and the Xiluodu hub only has a reserved position for navigation facilities, most cascades have not been built or reserved for navigation facilities because the navigation needs were not fully considered at the beginning of the design. This has greatly restricted the comprehensive utilization of regional water transport resources and the balanced development of the river basin economy.

[0003] In view of this situation, one of the traditional solutions is to directly transform the flood discharge gate, sacrificing some flood discharge functions to build navigation facilities. However, this solution not only affects the stability and safety of the main structure of the dam, but its applicability is limited to the type of concrete gravity dam with a relatively thick dam body. For arch dams with more delicate structures and relatively thin dam bodies, the implementation risk increases significantly, which may endanger the overall safety of the dam.

[0004] To overcome the above limitations, the industry has explored another innovative idea - combining navigation facilities with intermediate channels (long-distance tunnels). This plan uses flexible spatial layout to achieve the construction of navigation facilities away from the dam site, effectively avoiding direct interference with the main structure of the dam and ensuring the safety of the dam, such as the Three Gorges New Channel. However, there are several difficulties in the water transfer plan of the dispersed two-stage ship lock:

[0005] (1) During the discharge process of the first-level ship lock, if the ship lock water is discharged into the intermediate channel, the large discharge flow will deteriorate the water flow conditions in the intermediate channel, resulting in excessive flow velocity and fluctuation in the intermediate channel. At the same time, the large volume of water directly entering the intermediate channel will also cause the water level in the intermediate channel to fluctuate too much. When a tunnel is used in the intermediate channel of the two-level ship lock, in order to meet the navigation clearance requirements, the ship clearance height, ship draft, the surplus water depth of the intermediate channel, and the water level rise in the intermediate channel together determine the size of the tunnel. When the water level rises too much, the cost of tunnel construction will be too high and the construction difficulty will be too great.

[0006] (2) During the discharge process of the first-stage ship lock, if the lock water is directly discharged into the downstream river, the lock head will be too high when the first-stage ship lock is discharged. The excessively high head will cause a series of high-head ship lock problems, such as valve cavitation vibration, investment cost problems caused by the complex layout of the water delivery system, and water hammer problems caused by the high-head ship lock when it needs to be opened and closed quickly under accident conditions. The highest head ship lock currently built is the Datengxia ship lock, with a head of 40.25m. There is no actual engineering experience to guide the ship locks above this head, and there is no technical guarantee. At the same time, directly discharging the first-stage ship lock water into the downstream river will lead to a large amount of water consumption in the ship lock, which is inconsistent with the low-carbon and environmental protection concept proposed by today's society.

[0007] (3) During the filling process of the second-level ship lock, if the ship lock directly draws water from the middle channel, which corresponds to (1), it will also cause problems such as deterioration of water flow conditions in the middle channel and excessive fluctuation of water level in the middle channel. It may also cause the ship to hit the bottom and cause safety problems.

[0008] (4) During the filling process of the second-level ship lock, if the ship lock directly draws water from the upstream reservoir, which corresponds to (2), it will lead to problems such as excessive head and high water consumption during the filling process of the ship lock.

[0009] (5) Due to the water level changes upstream and downstream of the hub, when the amount of water discharged by the first-level ship lock into the middle channel is not equal to the amount of water taken in by the second-level ship lock in the middle channel, there is also the impact of the accumulated water level in the middle channel, which may cause the ship to hit the bottom or have insufficient clearance height. When the discharge and water intake of the ship lock have no relationship with the middle channel, the water in the middle channel will be stagnant for a long time, which will lead to the deterioration of the ecological environment of the water body in the middle channel.

[0010] Therefore, there is an urgent need for a water delivery solution to solve the difficulty of water delivery in two-level ship locks. Summary of the invention

[0011] In view of the shortcomings of the prior art, the present invention provides a two-stage dispersed cascade ship lock water delivery arrangement and a water storage channel water level control method. In the two-stage dispersed cascade ship lock system, the operating water head is reduced and the water level fluctuation is reduced to achieve efficient utilization of water resources and stable control of the water level in the intermediate channel.

[0012] To achieve the above objectives, the present invention is implemented through the following technical solutions: a two-stage decentralized cascade ship lock water delivery system, comprising a first-stage ship lock connected to an upstream reservoir, a second-stage ship lock connected to a downstream river channel, and an intermediate channel connecting the first-stage ship lock and the second-stage ship lock, characterized in that the water delivery arrangement includes:

[0013] The water-saving tanks are respectively installed beside the first-level ship lock and the second-level ship lock to reduce the operating head of the ship lock and save water for the ship lock operation;

[0014] The water storage channel located next to the middle channel is used to reduce the water head between the ship lock and the middle channel and the amount of water entering and leaving the middle channel through the ship lock, and to make the water head of the ship lock and the middle channel consistent, so that the water level in the middle channel is constant;

[0015] A water replenishment tank and an overflow tank 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, water replenishment tanks and overflow tanks are used to monitor water levels in real time;

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

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

[0019] Water supply pool area A bs Satisfy the formula:

[0020]

[0021] Among them, A c is the cross-sectional area of ​​the water storage channel, H ss H is the water level in the lock chamber after the first-stage ship lock releases water to the water-saving pool. sx H is the water level in the lock chamber after the water-saving pool of the second-level ship lock is filled with water, z is the water level in the middle channel, H umin is the lowest navigable water level upstream, and x is the initial water level of the water storage channel;

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

[0023]

[0024] Where y is the water level of the water storage channel after the lock chamber releases water into the water storage channel, H dmax It is the highest navigable water level downstream.

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

[0026] Preferably, the water level sensor in the water storage channel is arranged at the bottom of the water storage channel and a plurality of sensors are arranged along the longitudinal direction of the channel to measure the average water level in the water storage channel.

[0027] The present invention also provides a method for controlling the water level of a water storage channel of a two-stage dispersed 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 upstream and downstream water level difference;

[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 is started to discharge water to discharge the excess water downstream;

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

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

[0033] When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is equal to the water head in the middle channel, the formula is satisfied:

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

[0035] The water storage channel is in a state of equilibrium where it neither replenishes nor overflows;

[0036] When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is greater than the water head in the middle channel, the formula is satisfied:

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

[0038] Determine the overflow volume as:

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

[0040] When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is less than the water head in the middle channel, the formula is satisfied:

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

[0042] Determine the water replenishment amount:

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

[0044] Among them, H ssH is the water level in the lock chamber after the first-stage ship lock releases water to the water-saving pool. z is the water level in the middle channel, H sx is the water level in the lock chamber after the water-saving reservoir of the second-level ship lock is filled with water, A c is the cross-sectional area of ​​the water storage channel.

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

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

[0047] Determine the water level that needs to be lowered in the water replenishment pool according to the water replenishment amount, and open the drain valve of the water replenishment pool;

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

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

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

[0051] Determine the water level that needs to be raised in the overflow pool according to the overflow volume, and open the overflow pool 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 operation and the overflow operation, 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 channel to reduce the impact of water level fluctuations.

[0054] The invention provides a two-stage dispersed cascade ship lock water delivery arrangement and a water storage channel water level control method.

[0055] It has the following beneficial effects:

[0056] 1. The present invention reduces the amount of water directly discharged to the downstream river during the operation of the traditional ship lock through the layout design of the water-saving pool and the water storage channel, realizes the reuse of the water resources of the ship lock, significantly reduces the overall water consumption, and meets the requirements of water conservation and environmental protection.

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

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

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

[0060] 5. The present invention reduces the operating water head of the ship lock to the minimum through the synergistic effect of the water-saving pool and the water storage channel, avoids the water flow vibration and cavitation caused by high water head, and ensures the safety and durability of the ship lock structure.

[0061] 6. The filling and discharging process of the ship lock and the middle channel causes the water in the middle channel to be naturally replaced, which plays a positive role in improving the water quality of the middle channel and maintaining the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0063] Figure 2 The water head of the lock chamber and water storage channel of the embodiment of the present invention varies with m and k. c Schematic diagram of change relationship;

[0064] Figure 3 The water head of the lock chamber and the middle channel of the embodiment of the present invention varies with m and k. c Schematic diagram of change relationship;

[0065] Figure 4 The water saving rate of the embodiment of the present invention varies with m and k c Schematic diagram of the changing relationship. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] Please see attached Figure 1 The present invention provides a water delivery system for a two-stage decentralized cascade ship lock, which is designed as a "water saving pool + water storage channel" structure, specifically comprising:

[0068] Water-saving tank: Located next to the first and second level ship locks, it reduces the operating water head of the ship locks and performs water-saving operation of the ship locks.

[0069] Water storage channel: arranged parallel to the middle channel, reducing the water head between the ship lock and the middle channel and the amount of water entering and leaving the middle channel through the ship lock, and achieving consistency in the water head between the ship lock and the middle channel, so that the water level in the middle channel is constant.

[0070] Water replenishment tank and overflow tank: located upstream and downstream of the water storage channel, 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 tank provides additional water; when the water level is high, the overflow tank discharges excess water.

[0071] like Figure 1 As shown, the one-way operation process of the water delivery system of the two-stage dispersed cascade ship lock of the present invention is:

[0072] When the first-level ship lock is filled with water, the water-saving tank first fills the lock chamber, and then the upstream reservoir fills the lock chamber with water. Figure 1 The corresponding 1 and 2 processes;

[0073] When the first-level ship lock releases water, it first releases water to the water saving pool, then to the water storage channel, and finally to the intermediate channel. Figure 1 Process 3, 4, and 5;

[0074] When the second-level ship lock is filled with water, the water-saving tank first fills the lock chamber, then the water storage channel fills the lock chamber, and finally the intermediate channel fills the lock chamber. Figure 1 6, 7, 8 process;

[0075] When the second-level ship lock releases water, it first releases water to the water saving pool and then releases water to the downstream river channel. Figure 1 Process 9 and 10.

[0076] The present invention cleverly combines the reduction of the operating head of the ship lock with the minimization of the water volume in the middle channel. Through the water-saving pool and the water storage channel, it not only significantly reduces the operating head of the ship lock, but also realizes the effective control of the water volume entering the middle channel. At the same time, the scheme ensures the dynamic balance between the discharge and intake of water in the middle channel, maintains the stability of the water level in the middle channel, and provides a strong guarantee for the safe passage of ships. In addition, the filling and discharge process of the ship lock and the middle channel also promotes the natural replacement of the water body in the middle channel, which has a positive effect on improving the water quality of the middle channel and maintaining the ecological environment.

[0077] 1. The present invention provides a theoretical system for the layout of a water-saving tank + water storage channel water delivery system, which is as follows:

[0078] (1) Water storage channel layout theory

[0079] In order to ensure the water level balance between each level of water saving pool and the lock chamber during the water saving operation of the ship lock, the water saving pool is arranged as an open structure in the design, and its area ratio with the lock chamber is k c Assume that the number of water saving pools is m, and the water level downstream of the first-stage ship lock is the water level of the middle channel H z, the water level upstream of the second-level ship lock is the water level of the middle channel H z , the downstream water level of the second-level ship lock is the downstream river water level H d .

[0080] After the first-stage ship lock releases 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 water storage tank of the second-level ship lock is filled with water into the lock chamber, the water level of the lock chamber is recorded as H sx , the calculation formula is:

[0083]

[0084] Assuming that the initial water level of the water storage channel is x, when the first-stage ship lock chamber releases water into the water storage channel, the water level of the water storage channel will rise by a value Δh1, which is calculated as follows:

[0085]

[0086] Among them, A c is the area of ​​the lock chamber, A cs The area of ​​water storage channels.

[0087] When the water storage channel discharges water to the second-level ship lock, the water level of the water storage channel will decrease by a value Δh2, which is calculated as follows:

[0088]

[0089] In order to make the amount of water discharged from the ship lock to the middle channel equal to the amount of water taken from the middle channel, and to keep the water level in the middle channel constant after one cycle, the following relationship must be satisfied:

[0090]

[0091] Among them, H z is the middle channel water level.

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

[0093] y=x+Δh1 (6)

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

[0095]

[0096] By (7), we can calculate:

[0097]

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

[0099]

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

[0101]

[0102] (2) Theory of water level control and overflow in water storage channels

[0103] In order to maintain the dynamic water level balance of the middle channel and make the discharge and intake of the ship lock equal, water replenishment or overflow operation is required to control the initial water depth of the water storage channel. Theory of water replenishment and overflow based on the water level control of the water storage channel:

[0104] When the water level in the water storage channel returns to the initial value after operation, there is no need to perform water replenishment or overflow operations, that is, y-Δh2=x;

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

[0106] A cs (y-Δh2-x)

[0107] When the water level in the water storage channel is lower than the initial value, water replenishment is required, and the amount of water replenishment is:

[0108] A cs (x-(y-Δh2))

[0109] If the water heads of the first-level ship lock and the second-level ship lock are equal in the middle channel, the overflow water operation volume can be further simplified to the following formula:

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

[0111] When H ss -H z >H z -H sx When , the water storage channel overflows, and the overflow volume is:

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

[0113] When H ss -H z <H z -H sxWhen , the water storage channel is replenished, and the amount of water replenished is:

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

[0115] 2. The present invention provides the water level change and operating head and elevation arrangement during the operation of the ship lock

[0116] (1) First-stage ship lock filling

[0117] During the filling process of the first-level ship lock:

[0118] In the initial state, the water level in the lock chamber is the water level in the middle channel H z , the water level of the upstream reservoir 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 level water-saving tank is filled with water into the lock chamber, the water levels of the water-saving tank and the lock chamber are:

[0122]

[0123] The water heads of provincial water tanks and lock chambers at all levels are:

[0124]

[0125] After the water-saving pool is in operation, the upstream reservoir fills the lock chamber with water, and the water head between the lock chamber and the upstream reservoir area is:

[0126]

[0127] The water level in the lock chamber rises to the upstream water level H u , the first-level ship lock was filled with water.

[0128] (2) Discharge of the first-level ship lock

[0129] The initial water level of the lock chamber before the first-stage ship lock is the water level of the upstream reservoir H u , then the initial water level of the i-th level water-saving tank is the water level after the last water-saving tank filled the gate chamber, that is:

[0130]

[0131] The water head of the lock chamber and the water saving tank is:

[0132]

[0133] After the first-stage lock chamber discharges water to the i-th-stage water-saving tank, the water levels of the water-saving tank and the lock chamber are:

[0134]

[0135] The first-level ship lock releases water to the water storage channel, and the initial water level of the water storage channel is:

[0136] H cs =x (20)

[0137] The water head between the water storage channel and the lock chamber is:

[0138]

[0139] After discharge, the water level of the lock chamber and the water level of the water storage channel are:

[0140]

[0141] Among them, H cs is the initial water level of the water storage channel.

[0142] The first-stage ship lock discharges water to the middle channel, and the water head between the middle channel and the lock chamber is:

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

[0144] After the lock chamber discharges water into the middle channel, the water levels in the lock chamber and the middle channel are:

[0145]

[0146] (3) Second-level ship lock filling

[0147] The initial water level of the lock chamber before the second-stage ship lock is filled with water is the downstream river water level H d , the water level upstream of the lock chamber is the water level H of the last discharge from the intermediate channel 1xz , then the initial water level of the i-th level water saving pool is:

[0148]

[0149] After the i-th level water-saving tank is filled with water into the lock chamber, the water levels of the water-saving tank and the lock chamber are:

[0150]

[0151] The water head of each level of provincial water tank and lock chamber is

[0152]

[0153] Before the water storage channel is filled with water to the second-level ship lock, the initial water level of the water storage channel is H′ 1xcs, the water head between the water storage channel and the lock chamber is:

[0154]

[0155] After the water storage channel is filled with water to the second-level ship lock, the water levels of the water storage channel and the lock chamber become:

[0156]

[0157] The water head between the lock chamber and the middle channel is:

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

[0159] The middle channel fills the lock chamber with water, and the water levels in the lock chamber and the middle channel are:

[0160]

[0161] (4) Second-level ship lock discharge

[0162] The initial water level of the lock chamber before the second-stage ship lock is released is the water level of the middle channel H 2cz , the downstream river water level is H u , then the initial water level of the i-th level water-saving tank is the water level after the last water-saving tank filled the gate chamber, that is:

[0163]

[0164] The water head of the lock chamber and the water saving tank is:

[0165]

[0166] After the first-stage lock chamber discharges water to the i-th-stage water-saving tank, the water levels of the water-saving tank and the lock chamber are:

[0167]

[0168] The second-level ship lock releases water to the downstream river channel. The water head between the lock chamber and the downstream river channel is:

[0169] d xzd =H′ 2xs (m)-H d (35)

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

[0171] Through the above water level, the extreme working condition combination is calculated:

[0172] (1) Upstream maximum water level H umax ~The lowest water level downstream H dmin ;

[0173] (2) Upstream maximum water level H umax ~Highest downstream water level H dmax ,

[0174] (3) Upstream minimum water level H umin ~The lowest water level downstream H dmin ,

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

[0176] 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. According to experience, the bottom elevation of the water-saving pool is at least 1m lower than the lowest water level of the water-saving pool, the top elevation of the water-saving pool is at least 2m higher than the water-saving pool, the bottom elevation of the water storage channel is at least 2m lower than the lowest water level of the water storage channel, and the top elevation of the water storage channel is at least 4m higher than the highest water level of the storage channel.

[0177] 3. The present invention provides a water saving rate calculation theory

[0178] The combined navigation structure of two-stage ship lock + intermediate channel is dispersed. When the ship lock does not adopt water-saving measures, that is, the water discharged from the first-stage ship lock and the second-stage ship lock is directly discharged into the downstream river, the water consumption is 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] After the "water-saving pool + water storage channel" scheme is arranged, the first cycle process is the process of first-level ship lock filling-first-level ship lock discharge-second-level ship lock filling-second-level ship lock discharge. s V is the water volume discharged into the downstream navigation channel from the second-level ship lock x The amount of water V discharged into the downstream river through the overflow of the first-level ship lock y The sum is:

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

[0182]

[0183] Among them, when 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] Then the water saving rate ssl is:

[0188]

[0189] 4. The present invention provides a method for accurately controlling the water level in a water storage channel and an arrangement of a replenishment overflow pool

[0190] In order to achieve dynamic balance of the water body in the middle channel, the discharge of the ship lock is equal to the water intake of the ship lock. When the difference between the upstream and downstream water levels and the water level of the middle channel is not equal, overflow operation is required. The method of controlling the constant water level of the middle channel in this scheme is to control the initial water depth of the water storage channel.

[0191] According to the theory of water level control overflow in water storage channels, when H ss -H z =H z -H sx , the water storage channel does not fill or overflow, when H ss -H z >H z -H sx The water storage channel overflows, and the overflow amount is A c (H ss +H sx -2H z ); when H ss -H z <H z -H sx The water storage channel is replenished with water, and the amount of water replenished is A c (H ss +H sx -2H z ).

[0192] But there are two problems with precise control of water storage channels:

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

[0194] (2) When adjusting the water level of the water storage channel, water is filled or drained into the water storage channel. However, since the water surface of the water storage channel fluctuates 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 closing the valve. 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 tank is arranged on the upstream side of the water storage channel, and an overflow tank is arranged on the downstream side of the water storage channel. The area of ​​the water replenishment tank and the overflow tank should be as small as possible to reduce the requirement for high-precision measurement of the sensor. bs The overflow pool area A should be able to replenish the water required by the water storage channel at one time when the upstream minimum navigable water level is reached. ys It is necessary to discharge excess water at the highest navigable water level downstream at one time, namely:

[0196]

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

[0198] The corresponding overflow water replenishment operation of the water storage channel is:

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

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

[0201] Before the ship lock is operated, 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 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 water replenishment volume can be obtained by multiplying the difference between the initial water level and the current water level by the area of ​​the water storage channel. The required water level drop of the water replenishment pool can be obtained by dividing the water replenishment volume by the area of ​​the water replenishment pool. First, open the water replenishment pool filling valve, and close the valve after the water level of the water replenishment pool is flush with the upstream water level. Open the water replenishment pool discharge valve, and the water body enters the bottom gallery of the water storage channel through the water replenishment pool discharge gallery and enters the water storage channel through the top branch holes of 5 sections. When the water level drop of the water replenishment pool is equal to the calculated required water level drop, close the water replenishment pool discharge valve.

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

[0205] The overflow volume can be obtained by multiplying the difference between the initial water level and the current water level by the area of ​​the water storage channel. The overflow volume can be divided by the area of ​​the overflow pool to obtain the required water level of the overflow pool. First, open the overflow pool discharge valve, and close the discharge valve after the overflow pool is flush with the downstream water level. Open the overflow pool filling valve, and the water enters the bottom gallery of the water storage channel through the top branch hole of the water storage channel section 5 and enters the overflow pool from the top branch hole of the overflow pool. When the rising water level of the overflow pool is equal to the calculated required rising water level, close the overflow pool filling valve.

[0206] The above arrangement ensures the smooth transition of the ship lock and water storage channel during the filling and discharge process. The water level control of the graded water saving tank and the water level regulation of the water storage channel avoid the impact of water flow on the facility structure. Under extreme water level conditions, the water replenishment tank and overflow tank provide dynamic balance support, and the elevation design of the water saving tank and water storage channel ensures the safety of the system and continuous and stable operation.

[0207] In order to better understand the present invention, the above method is described in detail below in conjunction with specific embodiments.

[0208] Example:

[0209] Taking a certain project as an example, the "water-saving pool + water storage channel" scheme layout was carried out. The highest navigable water level in the upstream of the project was 293m, the lowest navigable water level was 278m, the highest navigable water level in the downstream was 227m, and the lowest navigable water level was 211.4m. Since the upstream water level fluctuation was equivalent to the downstream water level fluctuation, the lock head was divided by the equal head method. The total head was 81.6m, the single-stage lock head was 40.8m, and the middle channel water level was 252.2m. The two-stage locks were connected by an intermediate channel formed by a long-distance bidirectional tunnel. The area of ​​the intermediate channel was about 112586m 2 The water storage channel is arranged in parallel with the middle channel, with a total area of ​​26962 square meters and a lock chamber area of ​​5222m 2 To meet the navigable flow conditions in the long-distance tunnel, the water discharged into the intermediate channel shall not exceed 2.5m2 of the lock chamber area.

[0210] (1) The number of water tanks m and area k c Sure

[0211] The maximum water head during the operation of the ship lock occurs during the water delivery process between the water storage channel and the lock chamber, which determines the safety of the ship lock valve. The water head in the middle channel determines the water flow conditions in the middle channel. Figures 2 to 4 It can be seen that as m and k c As the m and k increase, the maximum water head and the water head from the lock chamber to the middle channel gradually decrease during the operation of the ship lock, and the water saving rate gradually increases, but the increase and decrease amplitude also increases with the m and k c The increase of k gradually decreases, that is, when m>3, k cAfter >2, increasing the number of water-saving tanks and the area of ​​water-saving tanks has no obvious effect on reducing the water head.

[0212] At the same time, in order to ensure the efficient operation of the ship lock, the ship lock operation time increases with the increase of the number of water saving tanks, so the number of water saving tanks needs to be reduced. c When it is equal to 0, it means that the lock does not save water. The head from the lock chamber to the middle channel reaches 44.4m, which exceeds the 40.25m head of the Datengxia lock, the current single-stage maximum head lock. c = 1, the maximum head is reduced to 29.6m, but it is also close to 30m head. c = 2, the maximum water head is reduced to 26.6m. Considering the safety of ship lock operation, water delivery time, project topography, water saving rate and investment, the project plans to use a level 1 water saving pool with an area twice that of the lock chamber.

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

[0214] After determining the number and area of ​​the water-saving tank, the elevation of the water-saving tank and the water storage channel must be determined. By calculating the water levels of various parts of the ship lock under extreme water level combination conditions, and arranging the elevations according to the surplus water depth of the water-saving tank being no less than 1m and the surplus water depth of the water storage channel being no less than 1.5m, the operating water level, water depth, head and other data under various conditions are shown in Tables 1 to 4.

[0215] Table 1 Water level changes during water delivery (293~211.4m)

[0216]

[0217] Table 2 Water level changes during water delivery (278~211.4m)

[0218]

[0219] Table 3 Water level changes during water delivery (293~227m)

[0220]

[0221] Table 4 Water level changes during water delivery (278~227m)

[0222]

[0223] (3) Determination of overflow pool

[0224] The overflow pool directly replenishes or discharges water to the water storage channel to adjust the initial water level of the water storage channel. According to formulas (42) and (43), the maximum water replenishment is 47,000 m 3 (278~211.4m water level combination), the maximum overflow is 48,900m3 (293~227m water level combination). To meet the overflow water volume, the overflow pool area is 2500m 2 The elevation of the bottom of the water replenishment tank needs to be lower than 259.2, so 254 is taken; the elevation of the bottom of the overflow tank needs to be lower than 229.44, so 206.7m is taken.

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

Claims

1. A two-stage decentralized cascade ship lock water delivery system, characterized in that: The water conveyance arrangement comprises a first-level ship lock connected to an upstream reservoir, a second-level ship lock connected to a downstream river channel, and an intermediate channel connecting the first-level ship lock and the second-level ship lock, wherein the water conveyance arrangement comprises: The water-saving tanks are respectively installed beside the first-level ship lock and the second-level ship lock to reduce the operating head of the ship lock and save water for the ship lock operation; The water storage channel located next to the middle channel is used to reduce the water head between the ship lock and the middle channel and the amount of water entering and leaving the middle channel through the ship lock, and to make the water head of the ship lock and the middle channel consistent, so that the water level in the middle channel is constant; A water replenishment tank and an overflow tank 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, water replenishment tanks and overflow tanks are used to monitor water levels in real time; The corridor set at the bottom of the water storage channel is used to control the flow of water between the water storage channel, the water replenishment tank and the overflow tank.

2. The two-stage decentralized cascade ship lock water delivery system according to claim 1 is characterized in that: The areas of the water replenishment pool and overflow pool meet the water demand under different extreme water level conditions: Water supply pool area A bs Satisfy the formula: Among them, A c is the cross-sectional area of ​​the water storage channel, H ss H is the water level in the lock chamber after the first-stage ship lock releases water to the water-saving pool. sx H is the water level in the lock chamber after the water-saving pool of the second-level ship lock is filled with water, z is the water level in the middle channel, H umm is the lowest navigable water level upstream, and x is the initial water level of the water storage channel; Overflow pool area A ys Satisfy the formula: Where y is the water level of the water storage channel after the lock chamber releases water into the water storage channel, H dmax It is the highest navigable water level downstream.

3. The two-stage decentralized cascade ship lock water delivery system according to claim 1 is characterized in that: Two water level sensors are arranged at the bottom of the water replenishment tank and the overflow tank respectively to measure the real-time water levels of the water replenishment tank and the overflow tank.

4. The two-stage decentralized cascade ship lock water delivery system according to claim 1 is characterized in that: The water level sensor in the water storage channel is arranged at the bottom of the water storage channel and a plurality of sensors are arranged along the longitudinal direction of the channel to measure the average water level in the water storage channel.

5. A method for controlling the water level of a water storage channel of a two-stage dispersed cascade ship lock, based on the two-stage dispersed cascade ship lock water delivery system according to any one of claims 1 to 4, characterized in that: The following steps are involved: Calculate the initial target water level of the water storage channel and determine the target water level based on the upstream and downstream water level difference; 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 is started to discharge water to discharge the excess water downstream; When the current water level is lower than the target water level, the water replenishment pool is started to replenish water from the upstream to the water storage channel.

6. The water level control method for the water storage channel of the two-stage dispersed cascade ship lock according to claim 5 is characterized in that: The step of calculating the initial target water level of the water storage channel comprises: When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is equal to the water head in the middle channel, the formula is satisfied: H ss -H z =H z -H sx The water storage channel is in a state of equilibrium where it neither replenishes nor overflows; When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is greater than the water head in the middle channel, the formula is satisfied: H ss -H z >H z -H sx Determine the overflow volume as: A c (H ss +H sx -2H z ) When the condition is met that the water head in the lock chamber after the first-level ship lock discharges water to the water-saving pool is less than the water head in the middle channel, the formula is satisfied: H ss -H z <H z -H sx Determine the water replenishment amount: A c (H ss +H sx -2H z ) Among them, H ss H is the water level in the lock chamber after the first-stage ship lock releases water to the water-saving pool. z is the water level in the middle channel, H sx is the water level in the lock chamber after the water-saving reservoir of the second-level ship lock is filled with water, A c is the cross-sectional area of ​​the water storage channel.

7. The water level control method for the water storage channel of the two-stage dispersed cascade ship lock according to claim 5 is characterized in that: The water replenishment operation comprises 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 A c To obtain the required water replenishment; Determine the water level that needs to be lowered in the water replenishment pool according to the water replenishment amount, and open the drain valve of the water replenishment pool; When the water level in the water replenishment tank drops to the calculated value, close the water replenishment tank drain valve.

8. The water level control method for the water storage channel of the two-stage dispersed cascade ship lock according to claim 5 is characterized in that: The overflow operation comprises 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 A c To obtain the overflow volume; Determine the water level that needs to be raised in the overflow pool according to the overflow volume, and open the overflow pool filling valve; When the water level in the overflow tank reaches the calculated value, close the overflow tank filling valve.

9. The water level control method for the water storage channel of the two-stage dispersed cascade ship lock according to claim 5, characterized in that: During the water replenishment operation and overflow operation, 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 channel to reduce the impact of water level fluctuations.

Images