Integrated pump station front pool suction vortex suppression structure

Abstract

The application provides a kind of integrated pump station front pool suction vortex suppression structure, including gate body, water pump, horn pipe and suction vortex suppression structure.The suppression structure is located upstream of gate body and surrounds horn pipe, including upper double-arched boss, bottom boss and two side bosses;Boss is respectively provided with flow guide surface towards suction port.The bottom of the flow limiting surface of the bottom boss is provided with a plurality of protrusions or / and pits.The application can effectively disperse water flow, release air, reduce bottom flow rate, significantly weaken the strength of suction vortex, improve water inflow flow pattern and prevent cavitation through the synergistic effect of multidirectional flow guide surface and the microstructure of flow limiting surface.The structure is compact and suitable for integrated pump gate, drainage pump station and other scenes.

Description

Technical Field

[0001] This invention relates to the field of hydraulic machinery and hydraulic optimization design technology for pumping stations, specifically to an integrated pumping station forebay suction vortex suppression structure. Background Technology

[0002] With the accelerating pace of urbanization, frequent extreme weather events and short-duration heavy rainfall have exacerbated urban flooding problems. To effectively address this challenge, integrated pumping stations, due to their advantages of small footprint, short construction period, and high degree of automation, are widely used in municipal drainage, rainwater lifting, and sewage transportation. However, in actual operation, the forebay area of ​​integrated pumping stations often experiences complex inflow conditions, insufficient submersion depth, and abrupt boundary changes, leading to the formation of suction vortices of various shapes near the pump inlet. These vortices not only entrain large amounts of air into the pump body but also induce gas-liquid two-phase flow, resulting in decreased pump efficiency, increased operating noise, uneven impeller stress, and in severe cases, cavitation damage, significantly shortening the equipment's service life.

[0003] To address the aforementioned issues, some improvements have been attempted in existing technologies. For example, some designs improve inlet conditions by increasing the volume of the forebay or adjusting the geometry of the inlet pool. While these methods can alleviate eddy current problems to some extent, they often require significant modification space and civil engineering investment, making them unsuitable for urban built-up areas with limited land. Other solutions attempt to alter the local flow field by installing simple guide vanes or retaining walls near the inlet. However, due to a lack of systematic fluid dynamics analysis and structural optimization, their guiding effect is limited, and they may even induce new flow separation or local backflow, thus exacerbating the non-uniformity of the flow pattern.

[0004] More importantly, existing integrated pumping stations are mostly gate-pump integrated structures. Due to limitations in gate size and installation space, traditional hydraulic optimization measures are often difficult to directly apply. How to effectively control the influent flow field within a limited space through a compact flow guiding structure design has become a technical challenge that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention analyzes the generation mechanism of suction vortices and finds that vortex formation is closely related to the flow distribution above, to the sides, and below the suction inlet. Simply relying on flow guidance in one direction is insufficient to completely eliminate vortex nuclei; multi-dimensional coordinated intervention is necessary. Therefore, this invention provides an integrated pump station forebay suction vortex suppression structure, aiming to solve the problems of turbulent flow at the suction inlet, frequent cavitation, and poor operational stability in existing technologies. It offers a compact, easy-to-install, and highly effective technical solution.

[0006] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0007] An integrated pump station forebay suction vortex suppression structure includes:

[0008] Gate assembly, installed at the water passage section of the pumping station;

[0009] A water pump is installed on the gate assembly;

[0010] A horn-shaped tube is connected to the suction port of the water pump;

[0011] A vortex suppression structure is provided upstream of the gate assembly and surrounds the horn tube.

[0012] The inhalation vortex suppression structure includes an upper boss located above the horn tube, a bottom boss located below the horn tube, and side bosses located on both sides of the horn tube.

[0013] The upper boss has an upper guide surface facing the horn tube;

[0014] The bottom boss has a bottom guide surface facing the horn tube;

[0015] The side boss has a side guide surface facing the horn tube;

[0016] Water flows into the trumpet tube after being guided by the upper guide surface, the bottom guide surface and the side guide surface.

[0017] Furthermore, the upper boss is a double-arch structure, and the arch height h of the upper boss and the diameter D of the suction port satisfy the following condition: 0.05D≤h≤0.15D; the distance L3 between the lowest point of the double-arch structure and the suction port satisfies the following condition: 0.25D≤L3≤0.75D.

[0018] Furthermore, the upper protrusion has at least one vent hole, which is located in the top area of ​​the upper protrusion; the opening of the vent hole is covered with an anti-clogging mesh.

[0019] Furthermore, the diameter Φ of the vent hole and the diameter D of the inlet satisfy the following condition: 0.05D≤Φ≤0.15D.

[0020] Furthermore, the angle θ1 between the side guide surface and the axis of the water pump satisfies: 10°≤θ1≤30°; the angle θ2 between the bottom guide surface and the axis of the water pump satisfies: 10°≤θ2≤30°.

[0021] Furthermore, the bottom protrusion also includes a flow-limiting surface located downstream of the bottom flow guide surface and connected to the bottom flow guide surface, the bottom of the flow-limiting surface having several protrusions and / or pits for reducing the flow velocity.

[0022] Furthermore, the distance L4 between the minimum flow cross section of the suction vortex suppression structure and the suction port satisfies: 1.5D≤L4≤3D; the distance L1 between each side boss and the suction port satisfies: 0.5D≤L1≤0.75D, where D is the diameter of the suction port.

[0023] Furthermore, the distance L2 between the bottom boss and the suction port satisfies: 0.75D≤L2≤D; the thickness d of the side boss and the bottom boss satisfies: 0.15D≤d≤0.35D, where D is the diameter of the suction port.

[0024] Furthermore, the water pump is an axial flow pump, and the gate assembly includes a gate for intercepting and regulating the water level, and a flap gate installed at the outlet.

[0025] The beneficial effects of this invention are as follows:

[0026] 1. The integrated pump station forebay suction vortex suppression structure of this invention, by setting up multi-directional protrusions above, below, and on both sides of the suction inlet, and forming a guide surface facing the suction inlet on each protrusion, allows the incoming flow to be simultaneously guided and rectified from multiple directions before entering the pump. This multi-directional coordinated flow guidance method can effectively disperse the large-scale vortex nucleus formed upstream of the suction inlet, forcing the fluid to enter the funnel tube with a more uniform flow profile, significantly improving the inlet flow pattern, thereby fundamentally weakening the generation intensity of the suction vortex.

[0027] 2. The integrated pump station forebay suction vortex suppression structure of this invention, by designing the upper boss as a double-arch structure and parameterizing the arch height h and the distance L3 between the lowest point of the arch and the suction inlet, allows the water flow to be symmetrically diverted and reconverged when passing above the suction inlet. This design effectively prevents the water flow from directly rushing down into the central region of the suction inlet, forming a local negative pressure zone, thereby disrupting the formation conditions of the central vortex, reducing the generation and accumulation of gas nuclei, and improving the gas phase stability of the incoming water.

[0028] 3. The integrated pump station forebay suction vortex suppression structure of this invention, by opening a vent in the top region of the upper boss and parameterizing the vent diameter Φ, and simultaneously installing an anti-clogging mesh, allows air entrained in the water flow or locally precipitated bubbles to be released in a timely manner, preventing gas from accumulating above the suction inlet and forming an air cushion layer. This reduces the interference of gas-liquid two-phase flow on pump performance and also prevents transient negative pressure fluctuations caused by gas compression and expansion, thus improving operational stability.

[0029] 4. The integrated pump station forebay suction vortex suppression structure of this invention optimizes and limits the angle range between the side guide surface and the pump axis, and between the bottom guide surface and the pump axis, allowing the incoming flow from both sides and the bottom to enter the suction inlet with a smoother trajectory. A reasonable guide surface inclination angle helps reduce the size of the flow separation zone, lowers the intensity of local vortices, improves the distribution of radial forces, and reduces impeller vibration and bearing wear caused by uneven flow.

[0030] 5. The integrated pump station forebay suction vortex suppression structure of this invention optimizes and limits the distances between the minimum flow cross-section of the suction vortex suppression structure and the suction inlet, the distances between the side protrusions and the suction inlet, and the distances between the bottom protrusions and the suction inlet. This ensures that the guiding structure neither interferes with the main flow due to excessively close distances nor loses its guiding effect due to excessively large distances. This refined spatial layout design maximizes the synergistic effect of each guiding surface without significantly increasing hydraulic losses.

[0031] 6. The integrated pump station forebay suction vortex suppression structure of the present invention avoids the problem of insufficient structural rigidity or vibration fatigue caused by excessively thin protrusions by parameterizing the thickness d of the side protrusions and bottom protrusions. At the same time, it also prevents the adverse effects of excessive flow cross-sectional contraction and increased flow resistance caused by excessively thick protrusions, thus achieving a good balance between structural strength and hydraulic performance.

[0032] 7. The integrated pump station forebay suction vortex suppression structure of this invention, by setting the water pump as a cross-flow pump structure and integrating the gate and flap gate, not only possesses excellent vortex suppression capabilities but also adapts to the limited installation space of integrated pump gates. The entire structure requires no additional land, is easy to construct and modify, and is particularly suitable for upgrading and new construction projects in urban built-up areas with limited land use, such as drainage pump stations and sewage lifting pump stations.

[0033] 8. The integrated pump station forebay suction vortex suppression structure of this invention, by setting several protrusions and / or pits at the bottom of the flow-limiting surface, causes local disturbances in the water flowing through the bottom protrusions when it comes into contact with these microstructures, increasing the flow resistance near the wall and thus effectively reducing the flow velocity at the bottom. This reduction in bottom velocity helps to decrease the velocity gradient below the suction inlet, preventing shear layer vortices formed due to excessively fast bottom flow and avoiding the expansion of the bottom backflow zone. Furthermore, the protrusions or pits can induce microscale vortices within the boundary layer. Although these microvortices are small in scale, they can effectively dissipate the energy of large-scale vortex nuclei, further weakening the vortex intensity entering the suction inlet. By optimizing the height and spacing of the protrusions or the depth and distribution density of the pits, fine-grained control of the bottom flow velocity can be achieved, allowing the bottom water to enter the suction inlet in a more stable state, avoiding the risk of local negative pressure and cavitation caused by excessively high flow velocities.

[0034] 9. The integrated pump station forebay suction vortex suppression structure of the present invention, by setting several protrusions and / or pits at the bottom of the flow-limiting surface, can increase the degree of turbulent mixing in the bottom boundary layer, improve the flow stability in the near-wall region, reduce the possibility of flow separation, thereby improving the adaptability and robustness of the entire suction vortex suppression structure.

[0035] 10. The integrated pump station forebay suction vortex suppression structure of this invention, through the coordinated design of the microstructure at the bottom of the flow-limiting surface and its upstream bottom guiding surface, allows the water flow to undergo further velocity regulation through the microstructure after initial guidance, forming a multi-stage regulation link of "guidance-deceleration-stabilization". This hierarchical flow control strategy can optimize the flow field distribution near the suction inlet to the maximum extent without significantly increasing the overall hydraulic loss, providing more uniform and stable water intake conditions for the pump impeller. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are some embodiments of the present invention. For those skilled in the art, it is obvious that other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the integrated pump station forebay suction vortex suppression structure described in this invention.

[0038] Figure 2 This is a three-dimensional diagram of the intake vortex suppression structure described in this invention.

[0039] Figure 3 for Figure 2 Top view and enlarged view of the vent.

[0040] Figure 4 for Figure 2 The main view.

[0041] Figure 5 for Figure 4 BB cross-sectional view.

[0042] Figure 6 for Figure 4 CC section view.

[0043] Figure 7 This is a schematic diagram of cavitation flow in a gate pump station system without the installation of an intake vortex suppression structure.

[0044] Figure 8 A schematic diagram of cavitation flow in a gate pump station system with an intake vortex suppression structure installed.

[0045] Figure 9 This represents the overall computational domain of the model of this invention and the comparative model.

[0046] Figure 10 This is the computational domain for the hydraulic components in the model of this invention and the comparative model.

[0047] Figure 11 This is a flowchart of the overall streamline of the model of this invention and the comparative model.

[0048] Figure 12 These are partial streamline diagrams of the model of this invention and the comparative model.

[0049] Figure 13 This is a diagram showing the center streamlines of the model of this invention and the comparative model.

[0050] In the picture:

[0051] 1-Gate assembly; 100-Gate; 110-Flap gate; 2-Water pump; 200-Motor; 210-Guide vane; 211-Impeller; 3-Bell tube; 310-Suction inlet; 4-Suction vortex suppression structure; 400-Upper boss; 401-Upper guide surface; 402-Ventilation hole; 403-Anti-clogging mesh; 410-Bottom boss; 411-Bottom flow limiting surface; 412-Bottom guide surface; 420-Side boss; 421-Side guide surface. Detailed Implementation

[0052] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0053] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "axial," "radial," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0054] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0055] like Figure 1 As shown, the integrated pump station forebay suction vortex suppression structure of the present invention is installed as a whole at the water passage section of the pump station, including a gate assembly 1, a water pump 2, a trumpet pipe 3, and a suction vortex suppression structure 4. The gate assembly 1, as a basic load-bearing component, is located at the water passage section of the pump station to achieve flow interception, water level regulation, and flood control functions. The water pump 2 is fixedly installed on the gate assembly 1 and adopts an axial flow pump structure, including a motor 200, guide vanes 210, and an impeller 211, for driving the water flow. The impeller 211, driven by the motor 200, rotates, and the guide vanes 210 are located downstream of the impeller 211. The trumpet pipe 3 is connected to the suction port 310 of the water pump 2, and its gradually expanding structure helps improve the inlet flow state and reduce hydraulic losses. The suction vortex suppression structure 4 is located upstream of the gate assembly 1 and surrounds the trumpet pipe 3, for guiding the water flow smoothly into the suction port and suppressing the generation of suction vortices at the suction port.

[0056] like Figures 2-6As shown, the suction vortex suppression structure 4 includes an upper boss 400, a bottom boss 410, and two side bosses 420. The upper boss 400 is located above the suction inlet and has a double-arch structure. Its surface is provided with an upper guide surface 401, and a vent 402 is opened at the highest point of the arch. In the case of water intake, air pockets or bubbles are released in time to avoid air accumulation forming an air cushion that could cause pump stall or generate large transient negative pressure. The double-arch structure is equivalent to arranging two symmetrical guide arches above the suction inlet, which allows the water flow to be dispersed and re-converged before entering the suction inlet. This can reduce the negative pressure zone generated by the water flow directly rushing down in the central area of ​​the suction inlet, thereby effectively weakening the formation of the central vortex. The vent 402 is covered with a stainless steel anti-clogging mesh 403, which serves to prevent clogging and water leakage. The arched guide surface 401 can effectively disperse the water flow entering the suction inlet, reduce the concentrated impact of the water flow, avoid the formation of a negative pressure zone, and weaken the generation of vortices.

[0057] The bottom boss 410 is located downstream of the suction inlet and includes a flow-limiting surface 411 and a bottom guide surface 412. The flow-limiting surface 411 is used to control areas with excessively high flow rates, while the bottom guide surface 412 helps to stabilize the water flow and guide it smoothly into the pump suction inlet. The side bosses 420 are symmetrically arranged on both sides of the suction inlet, and their inner sides are provided with side guide surfaces 421 to guide the lateral flow, ensuring it enters the pump body in the correct direction and reducing lateral vortices.

[0058] In specific implementation, the design parameters of the double-arch structure of the upper boss 400 are as follows: the ratio of the arch height h to the inlet diameter D satisfies 0.05 ≤ h / D ≤ 0.15, and the distance L3 from the lowest point of the arch to the inlet satisfies 0.25D ≤ L3 ≤ 0.75D. The arch curvature radius Rc and central angle are also specified. Determined by the following formula:

[0059] ,

[0060] .

[0061] In order to release air pockets or bubbles in a timely manner when water is introduced, reduce hydraulic loss, and avoid the formation of new eddies or separation zones, the number n of the vent holes 402 is 2 to 10, the hole diameter Φ satisfies 0.05D≤Φ≤0.15D, the number of hole rows E is 2 to 8, and they are installed at the highest point of the arch to facilitate gas escape.

[0062] The angle θ1 between the side guide surface 421 and the pump axis is determined through fluid dynamics analysis, and its value ranges from 10° to 30°. This angle aims to maximize the guiding effect of the water flow, reduce the impact of the water flow on the pump body, and reduce the influence of unbalanced forces on the pump station structure. Specifically, it is estimated by the following formula:

[0063]

[0064] In the formula, ΔP is the pressure drop caused by the guide surface, ρ is the fluid density, and V is the pressure drop caused by the guide surface. x V is the axial velocity component. t Let μ be the tangential velocity component and μ be the dynamic viscosity. Similarly, the angle θ2 between the bottom guide surface 412 and the axis of the pump 2 satisfies: 10°≤θ2≤30°.

[0065] To prevent flow separation and eddy currents, the distance L1 between the side boss 420 and the suction inlet satisfies 0.5D ≤ L1 ≤ 0.75D; the bottom boss 410 is further away from the suction inlet to ensure that it does not affect the suction flow, and the distance L2 between the bottom boss 410 and the suction inlet satisfies 0.75D ≤ L2 ≤ D. A boss that is too thin will cause deformation or vibration and poor stability, while a boss that is too thick may increase resistance and affect the flow efficiency of the water. Therefore, the boss thickness d is in the range of 0.15D ≤ d ≤ 0.35D to avoid structural vibration caused by excessive thickness or increased flow resistance caused by excessive thickness. The boss thickness d refers to the thickness of both the side boss and the bottom boss.

[0066] like Figure 5 As shown, the distance between the minimum flow section of the guide structure and the suction port is greater than 1 times the diameter of the suction port, which can significantly improve the uniformity of the water flow, reduce the intensity of the vortex, and improve the flow pattern. Therefore, in the embodiment, the distance L4 between the minimum flow section of the suction vortex suppression structure 4 and the suction port 310 satisfies: 1.5D≤L4≤3D.

[0067] On the side of the flow-limiting surface 411 facing the water flow, i.e. its lower surface, there are several protrusions and / or pits to locally decelerate and disturb the water flow at the bottom.

[0068] As an optional implementation, the protrusion is hemispherical or ellipsoidal, with a height h. p The relationship between the inlet diameter D and the suction port diameter is 0.01D≤h. p ≤0.05D. The diameter of the projected plane of the protrusion is d. p Its value range is 0.05D≤d p ≤0.1D. Multiple protrusions are arranged in an array along the length of the flow-limiting surface 411, with a center-to-center distance s between adjacent protrusions. p Satisfy 2d p ≤s p ≤4d p This ensures that sufficient flow resistance is generated without causing local blockage due to excessively small spacing. The protrusions can be manufactured by integral molding with the flow-limiting surface 411, or they can be attached to the surface of the flow-limiting surface through subsequent processing such as welding, bonding, or spraying.

[0069] As another optional implementation, the pit is a spherical concave surface or a conical concave pit, with a depth h. d The relationship between the inlet diameter D and the suction port diameter is 0.01D≤h. d ≤0.05D, pit opening diameter d d Satisfying 0.05D≤d d ≤0.1D. The pits are also distributed in an array pattern, with the edge spacing s between adjacent pits. d Controlled within 0.5d d up to 1.5d d Between these elements, a continuous surface texture is formed. The pit structure can be formed on the surface of the flow-limiting surface 411 through processes such as machining or etching.

[0070] To further enhance the deceleration effect, both protrusions and depressions can be simultaneously arranged on the same flow-limiting surface 411, with the two arranged alternately. For example, an array of protrusions can be set in the front half of the flow-limiting surface to initially disturb the boundary layer, while an array of depressions can be set in the rear half to further dissipate the vortex core energy. Alternatively, depending on the specific distribution of the bottom flow field, a denser microstructure can be set in the region with higher flow velocity, while a more sparse structure can be set in the region with lower flow velocity, in order to achieve differentiated control effects.

[0071] The working principle of the protrusions and / or recesses on the side of the flow-limiting surface 411 facing the water flow is as follows: When the bottom water flows through the flow-limiting surface 411, the protrusions increase the equivalent roughness of the wall, causing changes in the velocity distribution within the boundary layer. The low-velocity fluid layer near the wall thickens, thereby reducing the overall average velocity of the cross-section. The recesses, by forming local recirculation zones within them, consume the kinetic energy of the fluid. Simultaneously, the shear layer generated at the edge of the recesses induces micro-scale vortices. These vortices mix as they develop downstream, further dissipating the energy of the large-scale vortex cores. The combined effect of these two structures effectively reduces the velocity of the bottom water flow before it enters the inlet, resulting in a more stable flow pattern.

[0072] The dimensions of the aforementioned protrusions and pits are not fixed and can be optimized and adjusted according to specific working conditions in practical applications. For example, for pump stations with high flow velocities, h can be appropriately increased. p or h d To improve the deceleration effect; for sewage lifting scenarios with poor water quality, d can be appropriately increased. p or d d To reduce the risk of congestion. Numerical simulations and model experiments revealed that h p and h d By controlling the value within the range of 0.01D to 0.05D, a significant deceleration effect can be achieved without causing additional flow separation or hydraulic loss due to excessive structural size.

[0073] The gate assembly 1 includes a gate 100 for intercepting and regulating water level, and a flap gate 110 installed at the outlet. The gate 100 is installed at the water flow section of the pumping station to regulate the water flow. Its main functions include interception, water flow regulation, and flood control. The gate's opening and closing is controlled by an opening and closing device, which can automatically open or close according to changes in water level and flow rate, ensuring the normal operation of the pumping station at different water levels. The flap gate 110 is installed at the pumping station's outlet and automatically opens and closes based on the pressure difference of the water flow to prevent backflow and wasted hydraulic power.

[0074] Figure 7 The diagram shows the cavitation distribution around the inlet when no air vortex suppression structure is installed. It is evident that a large-scale air vortex forms above and to both sides of the inlet, generating significant local negative pressure in the vortex core region. This easily induces air to be drawn into the fluid along the vortex axis, forming bubble clusters and promoting the expansion of the cavitation region. Under this condition, the velocity distribution at the inlet exhibits significant non-uniformity, with strong coupling between rotating flow and local backflow. This leads to reduced stability of the inlet flow field, resulting in impeller stress fluctuations, increased cavitation tendency, and operational vibration and efficiency degradation. Figure 8 The diagram shows the cavitation distribution after implementing an air vortex suppression structure. By installing a double-arched flow divider above the inlet, the incoming flow is dispersed and smoothly converged, weakening the central negative pressure zone and air entrainment conditions at the source. The side guide surfaces reduce the intensity of the vortex nuclei on both sides of the intake air vortex; the bottom guide surface suppresses the development of bottom backflow, thereby weakening the generation and development of air vortices in the intake area as a whole. At this point, the flow near the intake is symmetrical and stable, and the cavitation range is significantly reduced.

[0075] To further verify the effectiveness of the structure of this invention, numerical simulation comparative analysis was conducted. For example... Figure 9 and Figure 10 As shown, numerical calculations were performed using Ansys CFX software. A three-dimensional incompressible turbulence model was selected to model the overall computational domain, including the inlet and external water body. The computational domain was set to a sufficiently large extended region in both the inflow and outflow directions to reduce the influence of boundary conditions on the inlet flow structure. A total pressure inlet was used as the inlet boundary to simulate the hydrostatic pressure conditions of the external environment; a mass flow rate outlet was used as the outlet boundary.

[0076] The performance data verification results are shown in Table 1. Under the same mass flow rate conditions, after installing the suction vortex suppression structure, the overall system efficiency increased from 43.78% to 61.36%, and the head increased from 0.997 m to 1.469 m, representing increases of approximately 40.2% and 47.3%, respectively. The results indicate that the suction vortex suppression structure can significantly improve the inlet flow quality, effectively reduce vortex-induced energy loss, and thus significantly improve the hydraulic performance of the waterjet propulsion system.

[0077] Table 1. Performance Data

[0078] No suppression device installed Install suppression device Increase Overall efficiency 43.78% 61.36% 40.2％ Head (m) 0.997 1.469 47.3％

[0079] like Figure 11 , Figure 12 As shown, without the suppression device, the streamlines at the pump inlet exhibit significant deflection and convergence in the inlet section, leading to an increased local pressure gradient and inducing the formation of a stable suction vortex structure. This suction vortex is primarily axially entrained, accompanied by radial backflow, causing the fluid to generate rotational momentum before entering the impeller, resulting in inlet flow field distortion and energy loss. Simultaneously, the vortex core region exhibits significant low-pressure characteristics, making it prone to becoming an initiation site for cavitation. After installing the suppression device, the inlet fluid is guided and redistributed, the streamline curvature is significantly reduced, the original suction vortex entrainment path is weakened or even destroyed, the vortex core strength decreases, and the fluid enters the pump body in a more axial manner, thereby suppressing the development of the suction vortex and improving the inlet flow regime. Figure 13 As shown, without the suppression structure installed, a typical suction vortex morphology can be observed near the pump inlet. This vortex is characterized by localized streamlines entanglement forming a spiral vortex core, with a significant velocity gradient between the vortex region and the main flow, exhibiting flow characteristics of both backflow and entrainment. This suction vortex not only alters the incoming flow angle of attack but also causes periodic pressure fluctuations. After installing the suppression structure, the inlet streamlines become straighter and more uniformly distributed, the original vortex core region disappears, and the fluid shear layer thickness decreases, indicating that the suction vortex is effectively weakened. Simultaneously, the main flow rate remains intact, allowing the fluid to enter the impeller region with a stable and uniform velocity field, thus mechanistically suppressing the formation conditions of the suction vortex.

[0080] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0081] The detailed descriptions listed above are merely specific illustrations of feasible embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. An integrated pump station forebay suction vortex suppression structure, characterized in that, include: Gate assembly (1) is installed at the water passage section of the pumping station; A water pump (2) is installed on the gate assembly (1); The horn tube (3) is connected to the suction port (310) of the water pump (2); A vortex suppression structure (4) is disposed upstream of the gate assembly (1) and surrounds the horn tube (3); The inhalation vortex suppression structure (4) includes an upper boss (400) above the horn tube (3), a bottom boss (410) below the horn tube (3), and side bosses (420) on both sides of the horn tube (3). The upper boss (400) has an upper guide surface (401) facing the horn tube (3). The bottom boss (410) has a bottom guide surface (412) facing the horn tube (3). The side boss (420) has a side guide surface (421) facing the horn tube (3). After being guided by the upper guide surface (401), the bottom guide surface (412) and the side guide surface (421), the water enters the trumpet tube (3).

2. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The upper boss (400) is a double-arch structure. The arch height h of the upper boss (400) and the diameter D of the inlet (310) satisfy the following condition: 0.05D≤h≤0.15D. The distance L3 between the lowest point of the double-arch structure and the inlet (310) satisfies the following condition: 0.25D≤L3≤0.75D.

3. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The upper boss (400) has at least one vent (402), which is located in the top area of ​​the upper boss (400); the opening of the vent (402) is covered with an anti-clogging mesh (403).

4. The integrated pump station forebay suction vortex suppression structure according to claim 3, characterized in that, The aperture Φ of the vent (402) and the diameter D of the inlet (310) satisfy the following condition: 0.05D≤Φ≤0.15D.

5. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The included angle θ1 between the side guide surface (421) and the axis of the water pump (2) satisfies: 10°≤θ1≤30°; the included angle θ2 between the bottom guide surface (412) and the axis of the water pump (2) satisfies: 10°≤θ2≤30°.

6. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The bottom boss (410) also includes a flow-limiting surface (411) located downstream of the bottom guide surface (412) and connected to the bottom guide surface (412), the bottom of the flow-limiting surface (411) having a number of protrusions and / or pits for reducing flow velocity.

7. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The distance L4 between the minimum flow cross section of the suction vortex suppression structure (4) and the suction port (310) satisfies: 1.5D≤L4≤3D; the distance L1 between each side boss (420) and the suction port (310) satisfies: 0.5D≤L1≤0.75D, where D is the diameter of the suction port (310).

8. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The distance L2 between the bottom boss (410) and the suction port (310) satisfies: 0.75D≤L2≤D; the thickness d of the side boss (420) and the bottom boss (410) satisfies: 0.15D≤d≤0.35D, where D is the diameter of the suction port (310).

9. The integrated pump station forebay suction vortex suppression structure according to claim 1, characterized in that, The water pump (2) is a cross-flow pump, and the gate assembly (1) includes a gate (100) for intercepting and regulating the water level and a flap gate (110) installed at the outlet.

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