Body type design method for diversion system vertical shaft and surge shaft combined arrangement turning section of pumped storage power station

Abstract

The invention discloses a pumped storage power station diversion system vertical shaft and surge shaft combined arrangement turning section shape design method, which carries out local three-dimensional CFD numerical calculation analysis on the combination part of a diversion vertical shaft and a surge shaft under constant flow and transient flow, and studies the flow field characteristics of the combination part of the vertical shaft and the surge shaft in different flow states. And the local head loss coefficient of the combination part of the turning section and the surge shaft is obtained, and the influence of hydraulic characteristics of different surge chamber arrangement body types is revealed.

Description

Technical Field

[0001] This invention relates to the field of pumped storage power station engineering technology, and in particular to a method for designing the shape of the turning section of the water intake system of a pumped storage power station by combining the vertical shaft and the surge tank. Background Technology

[0002] The combined arrangement of surge tanks and vertical shafts in pumped storage power stations reduces the number of vertical shafts from two to one. This optimizes construction, allowing for the use of a single set of equipment for both the surge tank and the vertical shaft. Furthermore, maintenance facilities can be installed on the top platform of the surge tank for convenient maintenance and repair of the vertical shaft. This is a growing trend in pumped storage power station layouts and has broad application prospects. However, compared to conventional arrangements, the combined arrangement of the surge tank and the intake shaft in pumped storage power stations involves a more unique flow channel layout, more complex flow field, and fewer engineering examples of this combination. There is also a lack of systematic theoretical research on the optimization of the design and hydraulic characteristics of this combined arrangement.

[0003] Many scholars have made pioneering contributions to the analysis of the hydraulic characteristics and design of surge tanks in pumped storage power stations. Liu et al. used computational fluid dynamics (CFD) to conduct three-dimensional numerical simulations of T-shaped branch surge tanks and compared the results with empirical formulas from model tests, verifying that CFD methods can accurately reveal the hydraulic characteristics of the corresponding surge tank structure and can be reliably used in surge tank design. Chen et al. used CFD methods to conduct numerical simulations of several typical surge tanks and found that the simulated surge tank loss coefficients had the same accuracy as those obtained from conventional hydraulic model tests, thus applying CFD methods to surge tank design calculations. Hua et al. used CFD methods to simulate the flow field and flow regime of the tailrace surge tank in a pumped storage power station, obtaining the flow regime and pressure distribution patterns inside the surge tank, providing a reference for surge tank design. In general, previous research on the hydraulic characteristics of surge tanks in pumped storage power stations has mainly focused on the arrangement of surge tanks without integrated surge wells, and has studied the local shape and bottom flow channel of the surge tank in isolation. Research on the combined arrangement of surge tanks and vertical shafts is relatively limited, and even less research has been conducted on the shape design and hydraulic characteristics of the combined area. Therefore, it is necessary to optimize the design and construction of surge tanks in pumped storage power stations by studying the hydraulic characteristics and structural optimization of the combined arrangement of water intake shafts and surge wells, in order to further promote the rapid construction and efficient operation of pumped storage power stations. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a design method for the shape of the turning section of the water intake system of a pumped storage power station, which combines vertical shafts and surge tanks, and to reveal the influence of different surge tank layout shapes on the constant flow hydrodynamic characteristics.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for designing the shape of the turning section of the water intake system of a pumped storage power station, which combines the vertical shaft and the surge tank, comprising the following steps:

[0006] S1. Establish the combined and non-combined layouts of the vertical shafts and surge tanks of the water diversion system. The calculation area of ​​the three-dimensional layout (i.e., the combined layout and the non-combined layout) is from the water inlet of the upstream water diversion tunnel to the surge tank and then to the unit inlet.

[0007] S2. Determine the unit flow boundary conditions based on the surge extreme conditions of the pressure regulating chamber, and sequentially perform grid division, monitoring point and monitoring surface setting for the combined and uncombined layout types to establish a CFD calculation model.

[0008] S3. Based on the CFD calculation model, perform steady flow calculation and analysis under different flow regimes for pumping and power generation under different water diversion system vertical shaft and surge tank layouts. Obtain flow velocity and pressure data of monitoring points and surfaces under steady flow, and analyze the velocity vector, pressure distribution flow field characteristics of the joint parts and the head loss coefficient of the turning section and surge tank.

[0009] S4. Based on the steady flow calculation in S3, continue to carry out transient flow calculation and analysis of different water diversion system vertical shaft and surge tank layouts, obtain flow velocity and pressure data of monitoring points and monitoring surfaces under transient flow, and analyze the surge wave and water breakdown chamber coefficient of surge tanks with different combined layout forms.

[0010] The process of establishing the combined layout of the water diversion system shaft and the surge tank includes: combining the turning section of the water diversion system with the connecting pipe of the surge tank to obtain the combined layout.

[0011] The process of establishing the non-connected arrangement of the vertical shaft and surge tank of the water diversion system includes: shifting the center line of the surge tank along the water diversion tunnel as a whole, while keeping other parameters unchanged, to obtain the non-connected arrangement.

[0012] In step S2, the boundary conditions include: using the upstream reservoir water level as the pressure reference, the pressure is 1 atm; a pressure function is given, the pressure function is related to the initial water level of the upstream water under the operating conditions, the unit inlet is set as the mass flow outlet, the top of the pressure regulating chamber is set as the pressure outlet, and the given relative pressure value is 0.

[0013] The formula for calculating the head loss coefficient is as follows:

[0014] ;

[0015] in, , These are the elevations of control sections 1 and 2, respectively. , These are the pressures at control sections 1 and 2, respectively. , The flow velocities at control sections 1 and 2 are respectively. For the characteristic cross-sectional velocity, , For density, It is the acceleration due to gravity. To control the head loss coefficient between sections 1 and 2, When the control section is located on both sides of the pressure regulating chamber, For flow coefficient, To control the hydraulic losses at sections 1 and 2, section 1 is section 1-1 and section 2 is section 2-2.

[0016] In this invention, to ensure the stability of the monitoring data, the control section (section) should be set away from locations of structural abrupt changes such as branch pipes (e.g., the junction of a bend and a pressure regulating shaft), and should preferably be 3 to 5 times the diameter of the corresponding section away from the location of structural abrupt changes.

[0017] The surge calculation process for the surge chamber includes:

[0018] A monitoring point is set above the center of the impedance orifice, with pressure P at the monitoring point. The change in the surge water level in the surge chamber is determined by the change in pressure at the monitoring point. The expression for the surge water level Z in the surge chamber is given. , The elevation of the monitoring point.

[0019] Water breakdown chamber coefficient The expression is: ; , ,in The steady-state flow velocity at section 1-1 To close the valve The cross-sectional velocity at time 1-1 To close The water head at section 1-1 of the piezometer. The steady-state flow velocity at section 2-2 To close the valve The cross-sectional velocity at time 2-2 To close The water head at section 2-2 of the piezometer. Let be the propagation velocity of the pressure wave at section 1-1. Let be the propagation velocity of the pressure wave at section 2-2.

[0020] As an inventive concept, the present invention also provides a terminal device, including a memory, a processor, and a computer program stored in the memory; the processor executes the computer program to implement the steps of the above method.

[0021] As an inventive concept, the present invention also provides a computer-readable storage medium having a computer program / instructions stored thereon; when the computer program / instructions are executed by a processor, they implement the steps of the above-described method.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] 1. This invention performs local three-dimensional CFD numerical calculation and analysis on the junction of the vertical water intake shaft and the surge tank under steady flow, studies the flow field characteristics of the junction of the vertical shaft and the surge tank under different flow conditions, obtains the local head loss coefficient of the junction of the turning section and the surge tank, and reveals the influence of different surge tank layout shapes on the hydraulic characteristics of steady flow.

[0024] 2. This invention uses a coupled CFD method based on the flow boundary calculated by one-dimensional transient process to reveal the flow field characteristics at the junction under transient flow, as well as its impact on the hydraulic design of surge tanks, the power station's regulation and protection performance, and operational stability, providing a scientific reference for the optimized design of surge tanks in pumped storage power stations. Attached Figure Description

[0025] Figure 1 A flowchart illustrating the method for designing and optimizing the shape of the turning section of the combined arrangement of vertical shafts and surge tanks in the water intake system of a pumped storage power station, as provided in an embodiment of the present invention.

[0026] Figure 2 The overall model of the calculation area of ​​the pumped storage power station provided in the embodiment of the present invention is shown in (a) as a combined arrangement of the water diversion system shaft and the surge tank, and (b) as a non-combined arrangement of the water diversion system shaft and the surge tank.

[0027] Figure 3 The flow boundary conditions for the unit under extreme surge conditions in the pressure regulating chamber in this embodiment of the invention are as follows: (a) is the flow boundary condition for the unit under the highest surge condition in the pressure regulating chamber, and (b) is the flow boundary condition for the unit under the lowest surge condition in the pressure regulating chamber.

[0028] Figure 4 These are the calculated monitoring sections under the combined arrangement of vertical shafts and surge tanks in the water diversion system in this embodiment of the invention.

[0029] Figure 5 shows the flow field characteristics of different flow regimes in the steady flow stage of the water diversion system with vertical shaft and pressure regulating well combined arrangement in the embodiment of the present invention. (a) is the velocity vector of the turning section under pumping operation, (b) is the velocity vector of the turning section under power generation operation, and (c) is the pressure distribution.

[0030] Figure 6 The flow field characteristics of the surge tank with different flow regimes are shown in the embodiment of the present invention, where the vertical shaft and surge tank of the water diversion system are combined. (a) is the velocity vector of the surge tank flowing out, and (b) is the velocity vector of the surge tank flowing in.

[0031] Figure 7 The following is a comparison of surge waves in surge chambers with different combined arrangement configurations in the embodiments of the present invention: (a) is a comparison of surge waves in surge chambers under the highest surge wave condition, and (b) is a comparison of surge waves in surge chambers under the lowest surge wave condition.

[0032] Figure 8 This is a comparison of the water breakdown chamber coefficients of different arrangement shapes in embodiments of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of 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, 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.

[0034] Example 1

[0035] This embodiment provides a method for designing and optimizing the shape of the turning section in the combined arrangement of vertical shafts and surge tanks in the water intake system of a pumped storage power station. The method includes steps S1-S4, as follows: Figure 1 As shown, the details are as follows:

[0036] S1 establishes a three-dimensional model of the water diversion system shaft and surge tank with and without combined arrangement. The calculation area of ​​the three-dimensional model is from the water inlet of the upstream water diversion tunnel to the surge tank and then to the unit inlet.

[0037] S2 meshes the 3D volumetric calculation region from step S1, determines boundary conditions, and sets monitoring points and surfaces to monitor data such as flow velocity and pressure, employing the finite volume method and Realizable... A comprehensive CFD calculation model was established for the turbulence model.

[0038] S3, based on the CFD calculation model in step S2, performs steady flow calculation analysis on the layout of vertical shafts and surge tanks in different water diversion systems. It acquires data such as flow velocity and pressure at monitoring points and surfaces under steady flow conditions, and analyzes the flow field characteristics, including velocity vectors and pressure distribution at the junctions, as well as the head loss coefficients at bends and surge tanks.

[0039] Building upon the steady-flow calculations in S3, S4 continues to conduct transient flow calculations and analyses for different layouts of vertical shafts and surge tanks in water diversion systems. It acquires data on flow velocity and pressure at monitoring points and surfaces under transient flow conditions, and analyzes hydraulic design parameters for surge tanks, such as surge waves and water breakdown coefficients, for different combined layout configurations.

[0040] More preferably, in step S1, the three-dimensional shape is constructed as follows:

[0041] The calculation area for the shape of the pumped storage power station's water intake system shaft and surge tank combined arrangement and non-combined arrangement is the entire water intake system, from the water intake tunnel inlet to the surge tank and then to the generator inlet. In the combined arrangement, the water intake shaft and surge tank are connected by a connecting pipe at the bend. In the non-combined arrangement, only the centerline of the surge tank is shifted along the water intake tunnel; all other parameters remain the same.

[0042] More preferably, in step S2, the CFD calculation model is performed as follows:

[0043] The three-dimensional computational domain established based on S1 was entirely meshed using hexahedral meshes, with mesh refinement applied to complex local areas. Mesh independence was verified considering computational accuracy, economics, and computation time. The turbulence model was implemented. Realizable model The coupling of pressure and velocity was performed using the SIMPLE algorithm, the velocity discretization scheme was second-order upwind, and the finite volume method (FVM) was used to discretize the computational domain and the governing equations into a series of control volumes (Yang Yang. Three-dimensional simulation calculation of groundwater pollution based on Fluent [D]. Jilin University, 2008).

[0044] More preferably, in step S2, the turbulence model is performed as follows:

[0045] The turbulence model includes equations for turbulent kinetic energy and turbulent dissipation rate, as shown below. Based on these equations, the flow characteristics in complex flow fields can be effectively captured, and data such as velocity and pressure at various points in the flow field can be obtained. This provides a reliable theoretical basis and numerical support for subsequent calculations of steady and transient flows.

[0046]

[0047]

[0048] in: , Time-averaged strain rate , For turbulent kinetic energy, For turbulent dissipation rate, It is due to the turbulent kinetic energy generated by the average velocity gradient. This represents the turbulent kinetic energy generated due to the effect of buoyancy; and It is a constant; and These are the Prandtl numbers, representing turbulent kinetic energy and its dissipation rate, respectively. The viscosity coefficient... It is not a constant; it is calculated using a formula: .

[0049] in, , , , Indicates angular velocity The average rotation tensor rate in the rotating reference frame. Model constants. , , ,in , .

[0050] More preferably, in step S3, the constant current calculation and analysis is performed according to the following method:

[0051] Based on the S2 calculation model, and given the steady flow calculation boundary, monitoring surfaces such as surge tanks and bends are set up to monitor flow velocity and pressure, obtaining velocity vector distribution and pressure distribution maps to study the flow field characteristics such as velocity and pressure. Based on the acquired flow velocity and pressure data, the head loss coefficients of bends and surge tanks are calculated. The loss coefficients are obtained using the following methods:

[0052] The hydraulic losses at sections 1-1 and 2-2 are selected as follows: From the energy equation, we get:

[0053]

[0054] in: , These are the elevations of control sections 1 and 2, respectively. , These are the pressures at control sections 1 and 2, respectively. , The flow velocities at control sections 1 and 2 are respectively. The cross-sectional flow velocity is... ,

[0055] For density, It is the acceleration due to gravity. To control the head loss coefficient between sections 1 and 2,

[0056] When the control section is located on both sides of the pressure regulating chamber, This is the flow coefficient.

[0057] More preferably, in step S4, the transient flow calculation and analysis are performed in the following manner:

[0058] Based on the S3 steady flow calculation, we will continue to carry out transient flow calculation and analysis, study the flow field characteristics such as velocity and pressure in the bend section and the surge tank under transient flow, obtain data such as flow velocity and pressure, and conduct comparative analysis on surge wave and water breakdown coefficient of surge tank under different layout forms.

[0059] The surge wave in the pressure regulating chamber is obtained using the following method:

[0060] A monitoring point is set above the center of the impedance orifice. By acquiring the pressure change data P at this point under transient flow, the change in surge water level in the surge chamber is obtained, and the expression for the surge chamber water level is derived. , The elevation of the monitoring point.

[0061] The water breakdown chamber coefficient is obtained by following these steps:

[0062] Based on data such as flow velocity and pressure at the monitoring surface, the formula for calculating the water breakdown chamber coefficient is as follows:

[0063]

[0064]

[0065] in For the water head of the piezometer, For distance, It is the acceleration due to gravity. The average flow velocity across the pipe cross-section. The Darcy-Weisbach coefficient of friction. The diameter of the pipe. The propagation speed of the pressure wave, The angle between the pipe and the horizontal plane.

[0066] Ignoring the compressibility of water and the friction of the pipe, it can be simplified to:

[0067]

[0068]

[0069] The basic equation for water hammer is:

[0070]

[0071]

[0072] in The head of the piezometer under steady-state flow conditions. The velocity inside the pipe in a steady-state flow condition. To close Time distance from the closing point The water head of the piezometer in m To close the valve Time distance from the closing point The cross-sectional velocity m For reverse pressure transmission wave, This is a pressure-transmitted wave. The maximum values ​​of the incident wave from the high-pressure water diversion pipeline and the incident wave from the water diversion tunnel are:

[0073]

[0074]

[0075] in The steady-state flow velocity at section 1-1 To close the valve The cross-sectional flow velocity at time 1-1 is for closed sections. Time 1-1 Section The water head in the pressure gauge; The steady-state flow velocity at section 2-2 To close the valve The cross-sectional velocity at time 2-2 To close The water head at section 2-2 of the piezometer. Let be the propagation velocity of the pressure wave at section 1-1. Let be the propagation velocity of the pressure wave at section 2-2.

[0076] Water breakdown chamber coefficient It can be represented as: .

[0077] The present invention will be further described below with reference to specific embodiments. Taking a pumped storage power station with a combination of vertical shaft and surge tank in a water diversion system as an example, the method of the embodiment of the present invention will be described in detail. Basic data of the power station: Elevation of the bottom plate of the surge tank is 579.0m, elevation of the bottom plate of the inlet is 594.0m, diameter of the surge tank well is 16m, pipe diameter is 9.5m, radius of the turning section is 10m, and diameter of the connecting pipe is 5m.

[0078] CFD calculations for steady flow conditions require a considerable amount of time to converge, unlike one-dimensional transient process calculations which can instantly obtain the initial steady flow field results. Before calculating the large-fluctuation transient process, the flow field was simulated for 1500 seconds with boundary conditions given for one-dimensional steady flow to obtain more accurate initial flow field conditions. The flow boundary conditions for the unit under the extreme surge condition in the surge chamber are as follows: Figure 3 As shown. To ensure stable monitoring data, monitoring surfaces should be located away from locations of structural abrupt changes, such as branch pipes. Each monitoring surface should be positioned as follows: Figure 4As shown in Figure 5, during the steady flow stage, there is no water exchange between the pipeline and the surge tank; the focus is on the connection between the bend and the vertical shaft. During the steady flow stage, power generation and pumping correspond to two flow regimes: water flowing towards the generator unit and water flowing towards the upstream reservoir, respectively. The flow field, flow regime, and pressure distribution at the connection are relatively regular, with no local anomalies. When the steady flow passes through the bend, the head loss is mainly localized at the bend, and the head loss coefficients for the bend are shown in Table 1. Ignoring friction loss caused by the monitoring surface location, the head loss coefficients are close to those calculated using empirical formulas, demonstrating the reliability of computational fluid dynamics methods for calculating head loss.

[0079] Table 1 Calculation of head loss at bends

[0080]

[0081] Pumped-storage hydropower stations bear the main responsibility for power grid peak shaving and frequency regulation. Load changes are more frequent, and unit operating conditions constantly shift between different operating points. This involves water flowing in and out of surge tanks. The flow pattern and the head loss coefficient of the surge tanks are as follows: Figure 6 As shown in Table 2.

[0082] Table 2 Head loss coefficient of surge tank well

[0083]

[0084] This study analyzes the comparison of surge water levels in surge chambers with different combined layout configurations. First, a monitoring point was established 3m above the center of the impedance orifice in the surge well of the power station, and its pressure P was monitored. Then, a simulation was performed using one-dimensional calculated flow rate change as the inlet boundary condition. Once the residuals of the governing equations converged below the threshold, the time-varying patterns of the surge water level in the surge chamber under the highest and lowest surge conditions were obtained. A comparison of surge water levels in surge chambers with different combined layout configurations is provided. Figure 7 As shown, the highest surge conditions for the two types of water level fluctuations have similar surge cycles, while the lowest surge conditions show that the lowest surge in the non-combined arrangement is lower than that in the combined arrangement.

[0085] In order to obtain the water breakdown chamber coefficient of the bottom pipeline of the surge tank, the flow velocity and piezometric head of the corresponding water diversion tunnel section and pressure pipeline section are monitored to obtain the water breakdown chamber coefficient of the pipeline under different working conditions. The water breakdown chamber coefficient is mainly related to the shape of the surge tank. Figure 8 To compare the water breakdown chamber coefficients of different layout types, it was found that the water breakdown chamber coefficient was smaller in the combined layout than in the non-combined layout, indicating that the combined layout of water diversion and surge tank has a better effect on water hammer wave reflection.

[0086] Example 2

[0087] Embodiment 2 of the present invention provides a terminal device corresponding to Embodiment 1 above. The terminal device can be a processing device for a client, such as a mobile phone, a laptop, a tablet computer, a desktop computer, etc., to execute the method of the above embodiments.

[0088] The terminal device in this embodiment includes a memory, a processor, and a computer program stored in the memory; the processor executes the computer program in the memory to implement the steps of the method in Embodiment 1 described above.

[0089] In some implementations, the memory may be high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk storage device.

[0090] In other implementations, the processor can be any type of general-purpose processor, such as a central processing unit (CPU) or a digital signal processor (DSP), and there is no limitation here.

[0091] Example 3

[0092] Embodiment 3 of the present invention provides a computer-readable storage medium corresponding to Embodiment 1 above, on which a computer program / instructions are stored. When the computer program / instructions are executed by a processor, they implement the steps of the method of Embodiment 1 above.

[0093] A computer-readable storage medium can be a tangible device that holds and stores instructions for use by an instruction execution device. A computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof.

[0094] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0095] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0096] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0097] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0098] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for designing the shape of a turning section in the water intake system of a pumped storage power station, combining vertical shafts and surge tanks, characterized in that... Includes the following steps: S1. Establish the combined and non-combined layouts of the water diversion system shafts and surge tanks. The three-dimensional shape calculation area extends from the upstream water diversion tunnel inlet to the surge tank and then to the unit inlet. S2. Determine the unit flow boundary conditions based on the surge extreme conditions of the pressure regulating chamber, and sequentially perform grid division, monitoring point and monitoring surface setting for the combined and uncombined layout types to establish a CFD calculation model. S3. Based on the CFD calculation model, perform steady flow calculation and analysis under different flow regimes for pumping and power generation under different water diversion system vertical shaft and surge tank layouts. Obtain flow velocity and pressure data of monitoring points and surfaces under steady flow, and analyze the velocity vector, pressure distribution flow field characteristics of the joint parts and the head loss coefficient of the turning section and surge tank. S4. Based on the steady flow calculation in S3, continue to carry out transient flow calculation and analysis of different water diversion system vertical shaft and surge tank layouts, obtain flow velocity and pressure data of monitoring points and monitoring surfaces under transient flow, and analyze the surge wave and water breakdown chamber coefficient of surge tanks with different combined layout forms.

2. The method for designing the shape of the turning section of the pumped storage power station's water intake system, combining vertical shafts and surge tanks, as described in claim 1, is characterized in that... The process of establishing the combined layout of the water diversion system shaft and the surge tank includes: combining the turning section of the water diversion system with the connecting pipe of the surge tank to obtain the combined layout.

3. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, which combines vertical shafts and surge tanks, as described in claim 1, is characterized in that... The process of establishing the non-connected arrangement of the vertical shaft and surge tank of the water diversion system includes: shifting the center line of the surge tank along the water diversion tunnel as a whole, while keeping other parameters unchanged, to obtain the non-connected arrangement.

4. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, which combines vertical shafts and surge tanks, as described in claim 1, is characterized in that... In step S2, the boundary conditions include: using the upstream reservoir water level as the pressure reference, the pressure is 1 atm; a pressure function is given, the pressure function is related to the initial water level of the upstream water under the operating conditions, the unit inlet is set as the mass flow outlet, the top of the pressure regulating chamber is set as the pressure outlet, and the given relative pressure value is 0.

5. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, which combines vertical shafts and surge tanks according to claim 1, is characterized in that... The formula for calculating the head loss coefficient is as follows: ； in, , These are the elevations of control sections 1 and 2, respectively. , These are the pressures at control sections 1 and 2, respectively. , The flow velocities at control sections 1 and 2 are respectively. For the characteristic cross-sectional velocity, , For density, It is the acceleration due to gravity. To control the head loss coefficient between sections 1 and 2, When the control section is located on both sides of the pressure regulating chamber, For flow coefficient, To control the hydraulic losses at sections 1 and 2; the control section 1 is section 1-1, and the control section 2 is section 2-2.

6. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, which combines vertical shafts and surge tanks, as described in claim 1, is characterized in that... The surge calculation process for the surge chamber includes: A monitoring point is set above the center of the impedance orifice, with pressure P at the monitoring point. The change in the surge water level in the surge chamber is determined by the change in pressure at the monitoring point. The expression for the surge water level Z in the surge chamber is given. , This refers to the elevation of the monitoring point.

7. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, combining vertical shafts and surge tanks, as described in claim 1, is characterized in that... Water breakdown chamber coefficient The expression is: ; , ,in The steady-state flow velocity at section 1-1 To close the valve The cross-sectional velocity at time 1-1 To close The water head at section 1-1 of the piezometer. The steady-state flow velocity at section 2-2 To close the valve The cross-sectional velocity at time 2-2 To close The water head at section 2-2 of the piezometer. Let be the propagation velocity of the pressure wave at section 1-1. Let be the propagation velocity of the pressure wave at section 2-2.

8. The method for designing the shape of the turning section of the water intake system of a pumped storage power station, combining vertical shafts and surge tanks according to claim 5 or 7, is characterized in that... The 1-1 section and 2-2 section are located at structural abrupt changes far from the branch pipe, and the distance between the section and the structural abrupt change is 3 to 5 times the diameter of the section.

9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory; characterized in that, The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program / instructions stored thereon; characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method according to any one of claims 1 to 8.

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