Drainage system for vertical shaft and pumped storage power station

Abstract

The invention discloses a vertical shaft and pumped storage power station drainage system, the vertical shaft comprises a vertical shaft main body, a tunnel connected with the side wall of the vertical shaft main body and a diversion pier vertically arranged in the tunnel, the diversion pier is connected with the vertical shaft main body, and the joints of the tunnel and the left and right side walls of the diversion pier and the vertical shaft main body are all of trumpet-shaped structures; the diversion pier divides the end of the tunnel into a first flow channel and a second flow channel, the first flow channel and the second flow channel are communicated with the vertical shaft body, and the left inner side wall and the right inner side wall of the first flow channel and the left inner side wall and the right inner side wall of the second flow channel are tangent to the inner side wall of the vertical shaft body. The vertical shaft solves the technical problem that in the prior art, the construction cost of an energy dissipation well is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of water conservancy and hydropower engineering, and particularly relates to a vertical shaft and a water discharge system of a pumped storage power station. Background Art

[0002] At present, green and low-carbon has become the main theme of the energy development era. Vigorously developing non-fossil energy and promoting the green and low-carbon transformation of energy have made positive contributions to the global energy transformation and sustainable development. The construction of hydropower stations and pumped storage power stations plays an important role in solving the energy shortage problem in the national economic development, improving the ecological environment, and promoting the coordinated and sustainable development of the regional economy.

[0003] Currently, countries around the world are actively facing climate change and promoting energy transformation. Hydropower stations and pumped storage power stations are bound to usher in a new wave of development and construction. In order to ensure the safe operation of water conservancy and hydropower projects and achieve the expected benefits at the design stage, as an important part of water conservancy and hydropower hub projects, whether the design of the water discharge structure is reasonable and whether it can safely discharge flood and dissipate energy directly affects the normal operation of the project hub.

[0004] As a water discharge structure often adopted in hydropower stations and pumped storage power stations, the vertical shaft is generally arranged in the reservoir area or in the mountain body. When discharging flood, there are generally two ways to enter the main body of the vertical shaft for flood discharge and energy dissipation. One is that the water flow drops vertically from the top of the main body of the vertical shaft into the main body of the vertical shaft, and after energy dissipation in the energy dissipation well, it enters the downstream river through the water withdrawal tunnel; the other is that the water flow enters the main body of the vertical shaft horizontally from the upper part of the main body of the vertical shaft through the water diversion channel, rotates in the main body of the vertical shaft, and enters the energy dissipation well under the action of gravity for energy dissipation. After energy dissipation, the water flow enters the downstream river through the water withdrawal tunnel. For the current way of flood discharge water flow entering the vertical shaft, the position where the water flow enters the vertical shaft needs to be arranged at the top or upper part of the main body of the vertical shaft, and the position where the water flow enters the vertical shaft is not flexible. At the same time, the water flow accelerates along the way in the main body of the vertical shaft and dissipates energy in the energy dissipation well at the bottom of the main body of the vertical shaft. To ensure flood discharge safety, the size of the energy dissipation well needs to increase with the increase of the water head and flow rate, and the construction cost of the energy dissipation well is relatively high. Summary of the Invention

[0005] Aiming at the current technical problems, the present invention aims to provide a vertical shaft and a water discharge system of a pumped storage power station, and this vertical shaft can solve the technical problem of relatively high construction cost of the energy dissipation well in the prior art.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A vertical shaft, including the main body of the vertical shaft, is characterized in that: it further includes a tunnel connected to the side wall of the main body of the vertical shaft and a flow dividing pier vertically arranged in the tunnel. The flow dividing pier is connected to the main body of the vertical shaft, and the connections between the left and right side walls of the tunnel and the flow dividing pier and the main body of the vertical shaft are both trumpet-shaped structures; the flow dividing pier divides the end of the tunnel into a first flow channel and a second flow channel, the first flow channel and the second flow channel are respectively connected to the main body of the vertical shaft, and the left and right inner side walls of the first flow channel and the second flow channel are tangent to the inner side wall of the main body of the vertical shaft.

[0007] Both sides of the tunnel and both sides of the flow dividing pier are tangentially connected to the main body of the vertical shaft. Water flow is introduced into the main body of the vertical shaft through the tunnel, and the flow dividing pier plays a role in dividing the water flow. The flow dividing pier divides the water flow into two strands, and the two strands of water flow enter the main body of the vertical shaft through the first flow channel and the second flow channel respectively. By utilizing the guiding effect of the arc-shaped side walls on both sides of the first flow channel and the second flow channel and the wall attachment characteristics of the water flow, it is promoted that the two strands of water flow smoothly enter the main body of the vertical shaft and then rotate along the side wall of the main body of the vertical shaft, and natural collision occurs in the main body of the vertical shaft. Through the collision effect of the two strands of water flow and the shear effect of the water flow in the main body of the vertical shaft, the energy of the water flow is dissipated in the main body of the vertical shaft, which can reduce the impact force of the flood discharge of the vertical shaft on the bottom plate of the energy dissipation well and the excavation depth of the energy dissipation well, thereby greatly reducing the construction cost of the energy dissipation well. In addition, the tunnel can be arranged at any elevation of the vertical shaft, and the position where the water flow enters the vertical shaft is more flexible.

[0008] Preferably, the flow dividing pier is arranged in the middle of the tunnel, and the first flow channel and the second flow channel are symmetrically arranged with respect to the flow dividing pier. Due to the symmetrical arrangement of the first flow channel and the second flow channel, the two strands of water flow entering the first flow channel and the second flow channel are symmetrical water flows, and the two strands of symmetrical water flows have natural collision in the main body of the vertical shaft, which can increase the water body energy dissipation rate.

[0009] Preferably, the tunnel is a horizontal tunnel, and the center line of the horizontal tunnel along the length direction is vertically intersected with the axial center line of the main body of the vertical shaft.

[0010] Preferably, the cross-sectional shape of the tunnel is a square, and the width of the square is R.

[0011] Preferably, the widths of the first flow channel and the second flow channel at the main body of the vertical shaft are both greater than 0.5R. The end widths of the first flow channel and the second flow channel are both greater than 0.5R, which can ensure that the flow velocity of the water flow entering the main body of the vertical shaft will not increase, thereby reducing the impact on the structure of the vertical shaft.

[0012] Preferably, the flow dividing pier is a symmetrical structure with respect to the vertical plane where the center line of the tunnel along the length direction is located, and the end of the flow dividing pier away from the main body of the vertical shaft is a streamline structure. Setting the pier head of the flow dividing pier as a streamline structure can reduce the influence of the water flow on the structure of the flow dividing pier, thereby ensuring the stability of the structure of the flow dividing pier.

[0013] To make the water flow diversion in the tunnel more uniform and stable, preferably, the cross-section of the end of the diversion pier away from the main shaft along the length direction is formed by the intersection of two arc segments, and the angle between the arc segment and the center line of the diversion pier is ε, where ε ≤ 90°.

[0014] Preferably, the end spacing of the two arc segments is D, where 0.1R ≤ D ≤ 0.2R.

[0015] Preferably, there are multiple tunnels, and the multiple tunnels are arranged along the height direction of the main shaft or are evenly arranged along the circumferential direction of the main shaft. The number of tunnels can be increased or decreased according to the size of the water discharge. When the multiple tunnels are evenly arranged along the circumferential direction of the main shaft, multiple water flows in the main shaft collide with each other, which can further increase the water flow efficiency.

[0016] Based on the same inventive concept, the present application also provides a water discharge system for a pumped-storage power station, including the above-mentioned shaft, and the main shaft is arranged in the reservoir area of the pumped-storage power station; a shaft slope reduction section is provided on the side wall of the main shaft, and the shaft slope reduction section is connected to the stilling basin through a drainage tunnel; the outer end of the tunnel is connected to a water discharge steel pipe through a diversion section, a valve is provided on the water discharge steel pipe, and the outer end of the water discharge steel pipe is used to be connected to the plug section of the diversion tunnel.

[0017] The diversion section is generally a transition section. When flood discharge is required, the valve is opened, and the water flow is introduced into the water discharge steel pipe, the diversion section and the tunnel through the diversion tunnel, and is divided into two water flows by the action of the diversion pier and enters the main shaft. After energy dissipation in the main shaft, it is introduced into the stilling basin through the shaft slope reduction section and the drainage tunnel.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a shaft and a water discharge system for a pumped-storage power station. By connecting the tunnel to the main shaft and using the diversion pier to divide the tunnel into two symmetric flow channels in the plane, and the flow channels are tangent to the main shaft, the water flow enters the main shaft from both sides along the wall through the guiding action of the diversion pier and the flow channels, forming a natural collision in the main shaft, increasing the water body energy dissipation rate, which can reduce the construction cost of the downstream energy dissipation building, and at the same time reduce the impact force of the shaft flood discharge on the bottom plate of the energy dissipation well, and can greatly reduce the excavation depth of the energy dissipation well. Brief Description of the Drawings

[0019] Figure 1 is a schematic structural diagram of the shaft of the present invention; Figure 2 is Figure 1 the sectional structural diagram of; Figure 3 is a schematic structural diagram of the water discharge system of the pumped-storage power station in Embodiment 1 of the present invention; Figure 4 is Figure 2Schematic diagram of the head structure of the middle diversion pier; Figure 5 is Figure 4 Schematic diagram of the calculation parameters of the arc curve of the head of the middle diversion pier; Figure 6 It is the flood discharge and energy dissipation effect diagram with one tunnel set on the main shaft body in Embodiment 1 of the present invention; Figure 7 It is the flood discharge and energy dissipation effect diagram with two tunnels provided on the main shaft body in Embodiment 1 of the present invention; Figure 8 It is the schematic diagram of the structure of the water discharge system of the pumped - storage power station in Embodiment 2 of the present invention; Figure 9 It is the flood discharge and energy dissipation flow pattern diagram in Embodiment 2 of the present invention; Figure 10 It is the flood discharge and energy dissipation flow pattern diagram of the prior art.

[0020] In the figure 1 - Main shaft body; 2 - Tunnel; 201 - First flow channel; 202 - Second flow channel; 3 - Diversion pier; 301 - Arc section; 4 - Diversion section; 5 - Water discharge steel pipe; 6 - Slope - pressing section of the shaft; 7 - Drainage tunnel; 8 - Stilling basin; 9 - Reservoir area of the pumped - storage power station; 10 - Valve; 11 - Downstream river; 12 - Chute. Detailed implementation manners

[0021] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments. It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. For the sake of convenience of description, words such as "upper", "lower", "left", and "right" hereinafter only represent the same directions as the upper, lower, left, and right directions of the drawings themselves, and do not limit the structure.

[0022] Embodiment 1:

[0023] Such as Figure 1 and Figure 2As shown in the figure, the vertical shaft of the present invention is adopted for the water discharge pipe of a pumped - storage power station, which includes a vertical shaft main body 1 and a tunnel 2 connected to the vertical shaft main body 1. The tunnel 2 is a horizontal tunnel, and the center line along the length direction of the horizontal tunnel is vertically intersected with the axial center line of the vertical shaft main body 1. The cross - sectional shape of the tunnel 2 is square, and the width of the square is R. The two sides of the tunnel 2 are tangentially connected to the vertical shaft main body 1 through arc ends, and the two arc segments are symmetrically arranged on the plane. A flow - dividing pier 3 is arranged in the middle of the tunnel 2. The head of the flow - dividing pier 3 is streamlined, and the two sides of the flow - dividing pier 3 are also tangentially connected to the vertical shaft main body 1 through arc segments, and the two arc segments are symmetrically arranged on the plane. The flow - dividing pier 3 divides the end of the tunnel 2 into a first flow channel 201 and a second flow channel 202. The first flow channel 201 and the second flow channel 202 are respectively connected to the vertical shaft main body 1, and the first flow channel 201 and the second flow channel 202 are symmetrically arranged with respect to the flow - dividing pier 3. The widths of the first flow channel 201 and the second flow channel 202 at the vertical shaft main body 1 are both greater than 0.5R. As Figure 4 shown, the cross - section along the length direction of the end of the flow - dividing pier 3 far from the vertical shaft main body 1 is formed by the intersection of two arc segments 301. The included angle between the arc segment 301 and the center line of the flow - dividing pier 3 is ε, and ε ≤ 90°. The end - to - end distance of the two arc segments 301 is D, and 0.2R ≤ D ≤ 0.4R.

[0024] As Figure 3 shown, the present embodiment also provides a water discharge system for a pumped - storage power station. The vertical shaft main body 1 is arranged in the reservoir area 9 of the pumped - storage power station. A vertical shaft slope - reducing section 6 is provided on the side wall of the vertical shaft main body 1. The vertical shaft slope - reducing section 6 is connected to a stilling basin 8 through a draw - off tunnel 7. The tunnel 2 is arranged below the vertical shaft slope - reducing section 6. The outer end of the tunnel 2 is connected to a water - discharge steel pipe 5 through a diversion section 4. The inlet of the water - discharge steel pipe 5 is connected to the plug section of the diversion tunnel. A valve 10 is arranged at the inlet of the water - discharge steel pipe 5 to control the flood discharge of the water - discharge steel pipe 5.

[0025] The cross - sectional shape of the tunnel 2 is square, and the width R is 2m. The flow state of the water flowing from the water - discharge steel pipe 5 into the tunnel 2 remains stable. The head of the flow - dividing pier 3 is formed by the intersection of two arc segments 301. The included angle between the arc segment 301 and the horizontal line is and is not greater than 45°. The end width D of the flow - dividing pier 3 is 0.35m (0.2m < 0.35m < 0.4m). The shape of the head of the flow - dividing pier 3 adopts an arc curve, which can make the water flow in the flow channel more uniform, stable and with less head loss. As Figure 5 shown, let the included angle between the side wall of the flow - dividing pier 3 and the center line be , and the included angles between the tangents of the two arc segments 301 and the center line of the flow - dividing pier 3 are both . When , the shape of the head is pointed - circular (or streamlined). Through calculation, the design formula for the curve parameters of the arc segment 301 can be obtained: (Formula 1)

[0026] The radius of the circular arc section 301 can be calculated as = 0.35 / (2 * (1 - cos45°)) = 0.6 m. The radii of the circular arcs on both sides of the tunnel 2 and the splitter pier 3 are both 2 m, and the circular arc angles are both 40°.

[0027] As Figure 4 and Figure 5 shown, the derivation process of the above Formula 1 calculation formula is as follows: Let: the curve radius of the circular arc section 301 , the horizontal length of the curve of the circular arc section 301 , .

[0028] , , According to the trigonometric function relationship, there are: , , , Also because: , so: , Substitute into the formula and simplify to get: , Also because: , so , When , the radius of the circular arc curve can be obtained as .

[0029] The top elevation of the tunnel 2 is slightly lower than the bottom outlet elevation of the pressure slope section 6 of the vertical shaft, ensuring that there is a pressurized flow in the tunnel 2 during the flood discharge of the water discharge steel pipe 5. The water flows from the tunnel 2 into the vertical shaft main body 1 in a submerged state, and the water dissipates energy at the bottom of the vertical shaft main body 1. The splitter pier 3 plays a role in splitting the flow. At the same time, by using the guiding effect of the side walls of the arc sections on both sides and the wall attachment characteristics of the water flow, the water flow is promoted to be divided into two symmetric water flows after entering the vertical shaft main body 1, which respectively rotate along the side walls of the vertical shaft main body 1 and collide inside the vertical shaft main body 1. Through the collision of the two water flows and the shear action of the water flow inside the vertical shaft main body 1, the energy of the water flow is dissipated inside the vertical shaft main body 1.

[0030] As Figure 6As shown in the figure, when the flood discharge flow rate is less than 40 m³ / s, only one tunnel 2 can be set. Under the flow splitting effect of the head of the flow splitting pier 3 and the guiding effect of the side walls of the arc sections on both sides of the first flow channel 201 and the second flow channel 202, the water flow is evenly divided into two water flows that adhere to the wall and enter the main shaft body 1, forming a collision water flow. At the same time, the water flow is in the submerged water body, and the internal shear of the water body is fully developed, greatly improving the energy dissipation rate of the water body. Among them, the numbers in the figure represent the flow velocity of the water flow. For example Figure 7 As shown in the figure, when the reservoir discharge exceeds 40 m³ / s, two tunnels 2 can be arranged circumferentially around the main shaft body 1. The two tunnels 2 are arranged oppositely, so that the water flow is divided into multiple water flows in the main shaft body 1 and forms an effective collision, and the energy dissipation effect is better. Among them, the numbers in the figure represent the flow velocity of the water flow.

[0031] The conventional water discharge steel pipe 5 is arranged at the bottom of the water discharge tunnel 7 and is connected to the stilling basin 8 along the water discharge tunnel 7. In Embodiment 1 of the present invention, the water discharge steel pipe 5 is connected to the main shaft body 1 through the tunnel 2, and collision energy dissipation is formed in the main shaft body 1, reducing the length of the water discharge steel pipe 5 by about 600 m. At the same time, the scale of the stilling basin 8 and the excavation depth of the main shaft body 1 can also be greatly reduced, effectively ensuring flood discharge safety and saving project construction costs.

[0032] Embodiment 2:

[0033] For example Figures 8 to 10 As shown in the figure, Embodiment 2 of the present invention is a shaft of a certain hydropower station at the outlet of the spillway chute using the present invention, and the structure of this shaft is the same as that in Embodiment 1. The water discharge system of the pumped-storage power station in this embodiment includes a spillway chute 12. When the spillway chute 12 is close to the downstream river channel, it is connected to the main shaft body 1 through a tunnel 2, and a flow splitting pier 3 is used at the connection of the tunnel 2 and the main shaft body 1 to split the downstream water flow. The water flow rotates along the wall in the main shaft body 1 and forms a natural collision on the other side of the main shaft body 1. The collided water flow naturally drops to the bottom of the main shaft body 1, and then the downstream water flow is discharged into the downstream river channel 11 through the water discharge tunnel 7.

[0034] For example Figure 9 As shown in the figure, when a conventional hydropower station generally uses a spillway chute 12 for flood discharge, the flow velocity of the water flow is relatively large. Due to the limited width of the downstream river channel, the water flow enters the downstream river channel 11 through flip bucket flow. The flow velocity of the water flow continuously accelerates in the air, and the flow velocity reaching the water surface is 20 m / s, which will cause serious scouring to the opposite bank of the downstream river channel, there are flood discharge safety problems, and at the same time, due to flip bucket energy dissipation, there is also a atomization problem downstream. Among them, the numbers in the figure represent the flow velocity of the water flow.

[0035] For example Figure 10As shown, through the diversion effect of the diversion pier 3, the water flow in this embodiment forms impact energy dissipation in the main shaft body 1, and the energy is basically dissipated in the main shaft body 1. The water flow can smoothly enter the downstream river channel 11, and the flow velocity entering the river channel is relatively low. The flow velocity reaching the opposite bank of the river channel is only 2 m / s to 4 m / s, and it will not cause scouring effect on the opposite bank of the river channel. The water mist during the energy dissipation process is concentrated in the main shaft body 1, which can effectively solve the problem of downstream atomization and improve the safety of the downstream river channel.

[0036] The content clarified in the above embodiments should be understood that these embodiments are only used to illustrate the invention more clearly, rather than to limit the scope of the invention. After reading the present invention, various equivalent forms of modification of these embodiments by those skilled in the art all fall within the scope defined by the appended claims of the present invention.

Claims

1. A vertical shaft, comprising a vertical shaft main body (1), characterized in that: It also includes a tunnel (2) connected to the side wall of the shaft main body (1) and a flow dividing pier (3) vertically arranged in the tunnel (2). The flow dividing pier (3) is connected to the shaft main body (1), and the connections between the left and right side walls of the tunnel (2) and the flow dividing pier (3) and the shaft main body (1) are both trumpet-shaped structures; The flow dividing pier (3) divides the end part of the tunnel (2) into a first flow channel (201) and a second flow channel (202). The first flow channel (201) and the second flow channel (202) are respectively connected to the shaft main body (1), and the left and right inner side walls of the first flow channel (201) and the second flow channel (202) are tangent to the inner side wall of the shaft main body (1).

2. The shaft according to claim 1, wherein: The flow dividing pier (3) is arranged in the middle of the tunnel (2), and the first flow channel (201) and the second flow channel (202) are symmetrically arranged with respect to the flow dividing pier (3).

3. The shaft according to claim 2, characterized in that: The tunnel (2) is a horizontal tunnel, and the center line of the horizontal tunnel in the length direction is vertically intersected with the axial center line of the shaft main body (1).

4. The shaft according to claim 3, characterized in that: The cross-sectional shape of the tunnel (2) is square, and the width of the square is R.

5. The shaft according to claim 4, characterized in that: The widths of the first flow channel (201) and the second flow channel (202) at the shaft main body (1) are both greater than 0.5R.

6. The shaft according to claim 4, characterized in that: The flow dividing pier (3) is a symmetric structure with respect to the vertical plane where the center line of the tunnel (2) in the length direction is located, and the end of the flow dividing pier (3) far from the shaft main body (1) is a streamlined structure.

7. The shaft according to claim 6, characterized in that: The cross-section of the end of the flow dividing pier (3) far from the shaft main body (1) in the length direction is formed by the intersection of two arc segments (301). The included angle between the arc segment (301) and the center line of the flow dividing pier (3) is ε, and ε ≤ 90°.

8. The shaft according to claim 7, characterized in that: The end spacing of the two arc segments (301) is D, and 0.1R ≤ D ≤ 0.2R.

9. The shaft according to any one of claims 1 to 8, characterized in that: There are multiple tunnels (2). The multiple tunnels (2) are arranged along the height direction of the shaft main body (1), or the multiple tunnels (2) are evenly arranged along the circumferential direction of the shaft main body (1).

10. A water discharge system for a pumped-storage power station, characterized in that: It includes the shaft as described in any one of claims 1 to 9. The shaft main body (1) is arranged in the reservoir area (9) of the pumped-storage power station; a shaft slope protection section (6) is provided on the side wall of the shaft main body (1), and the shaft slope protection section (6) is connected to the stilling basin (8) through a drainage tunnel (7); the outer end of the tunnel (2) is connected to a water discharge steel pipe (5) through a guide section (4). A valve (10) is provided on the water discharge steel pipe (5), and the outer end of the water discharge steel pipe (5) is used to be connected to the plug section of the diversion tunnel.

Images