An anti-cavitation device for an overflow dam

Abstract

The application relates to an overflow dam anti-cavitation device, which comprises a panel laid on the surface of the overflow dam, a plurality of air holes are formed in the panel, a pressure sensor is installed on the surface of the panel and used for monitoring the pressure of the water body near the panel, a pressure increasing module is communicated with the air holes, a control module is signal-connected with the pressure sensor and the pressure increasing module respectively, the pressure increasing module is controlled to start or stop according to the pressure data monitored by the pressure sensor, and the control module controls the pressure increasing module to start when the water body pressure is lower than a preset threshold value, air is injected into the water body through the air holes to increase the local pressure. Compared with the prior art, the application has the advantages of real-time monitoring and active protection, high intelligence and automation, wide adaptability, high reliability, convenient maintenance and the like.

Description

Technical Field

[0001] This invention relates to the field of water conservancy engineering technology, and in particular to an anti-cavitation device for spillway dams. Background Technology

[0002] To effectively utilize water resources and improve power generation efficiency, spillway dam construction is increasingly trending towards high head and large unit width flow rates. During spillway discharge, the special shape of the dam face and the high-speed flow of water easily create localized low-pressure zones. When the water pressure is lower than the saturated vapor pressure, some water vaporizes, and dissolved gases escape, forming bubbles – a process known as cavitation. When these bubbles enter areas of higher pressure with the water flow, they suddenly collapse, losing their conditions for existence. The movement of the liquid around the original bubbles causes a sudden increase in pressure in the localized area. As the continuously forming bubbles collapse near the spillway dam face, the dam face is subjected to repeated impacts of enormous pressure, leading to material fatigue damage and even surface erosion – a phenomenon called cavitation erosion. Cavitation and cavitation erosion severely affect the stability and service life of the dam. At the Yuzixi Hydropower Station in Sichuan, severe cavitation damage to the turbines resulted in a 50% reduction in the unit's overhaul cycle and a single unit maintenance cost of up to 600,000 yuan, seriously impacting power production.

[0003] In existing technologies, common physical protective measures, such as membrane coating, are used to improve the smoothness of the dam surface and reduce bubble formation. However, these methods are costly in practice, and the membranes are prone to peeling off, have a short lifespan, and cannot provide continuous protection against cavitation erosion. Numerous engineering examples demonstrate that aeration erosion reduction technology is one of the effective means to address cavitation damage. Aeration erosion reduction technology involves setting up aeration sills, aeration channels, and other structures in the high-speed water flow zone of spillway structures. The turbulence of the high-speed water flow introduces a large amount of air into the water flow, forming a water-air mixture. This mixture increases the compressibility of the water, buffering the impact force generated by bubble collapse, and can greatly reduce or even prevent cavitation damage. However, many current aeration facilities fail to provide adequate protection due to inadequate design. Therefore, a new type of cavitation prevention device is urgently needed to effectively solve the cavitation erosion problem of spillway dams. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an overflow dam anti-cavitation device that features real-time monitoring and active protection, high intelligence and automation, wide applicability, high reliability and convenient maintenance.

[0005] The objective of this invention can be achieved through the following technical solutions: This invention provides an anti-cavitation device for spillway dams, comprising: A panel is laid on the surface of the overflow dam, and the panel has multiple ventilation holes. A pressure sensor, mounted on the surface of the panel, is used to monitor the pressure of the water near the panel; The booster module is connected to the vent. The control module is connected to the pressure sensor and the booster module respectively, and is used to control the start and stop of the booster module according to the pressure data monitored by the pressure sensor; When the control module detects that the water pressure is lower than a preset threshold, it controls the pressurization module to start, injecting air into the water through the vent to increase the local pressure.

[0006] Furthermore, the booster module includes: Miniature air pumps are used to generate compressed air; The jet nozzle is connected to the output end of the micro air pump, and the outlet end of the jet nozzle is connected to the vent. The jet direction and flow rate of the jet nozzle are adjustable to adapt to different water flow conditions and dam structures.

[0007] Furthermore, the pressurization module is connected to the vent via a vent pipe.

[0008] Furthermore, the vent pipe is a flexible vent pipe used to transport compressed air.

[0009] Furthermore, the pressure sensor is installed in an area sensitive to changes in water flow pressure.

[0010] Furthermore, the pressure sensor is installed in the middle of the panel.

[0011] Furthermore, the panel adopts a modular structure, with its size and shape matched to the structure of the spillway dam, and is made of water-resistant and corrosion-resistant materials.

[0012] Furthermore, the vents are arranged in an array on the panel.

[0013] Furthermore, the booster module adopts a modular structure, with each booster module connected to a row of vents to form an independent monitoring and booster unit.

[0014] Furthermore, multiple pressure sensors are provided. The number and distribution density of the pressure sensors can be adjusted according to the complexity of the spillway and the monitoring accuracy requirements.

[0015] The control module employs automated control technology, enabling intelligent control. The device can achieve real-time monitoring, data analysis, and automatic adjustment through the control system to form a water-air mixture, buffering the impact force generated by bubble collapse.

[0016] Compared with the prior art, the present invention has the following advantages: (1) Real-time monitoring and active protection. The device monitors the water pressure on the overflow dam surface in real time through pressure sensors. When the pressure is detected to be lower than the preset threshold that may trigger cavitation, the control module can immediately and automatically start the pressurization module to inject air into the water to increase the local pressure. This realizes the transformation from "passively bearing damage" to "actively preventing cavitation", and can intervene in the early stage of cavitation, thereby effectively preventing subsequent cavitation damage and significantly improving the safety and operational reliability of the dam.

[0017] (2) High degree of intelligence and automation. The entire monitoring, analysis and control process is completed automatically by the control system without human intervention. The system can analyze sensor data in real time and precisely control the start and stop of the micro air pump, with fast response speed and high operating efficiency. This greatly reduces the difficulty and operating cost of manual monitoring and ensures the timeliness and consistency of protective measures.

[0018] (3) High flexibility and wide adaptability. Modular structure: The panel, pressurization module, etc. are all modularly designed, which allows the device to be customized and configured according to different types, sizes and curved shapes of overflow dams, just like assembling components, with excellent versatility. Adjustable parameters: The number and distribution density of pressure sensors, the jet direction and flow rate of the jet head, etc. can all be adjusted according to specific engineering needs and water flow conditions to ensure the best protection effect under different working conditions.

[0019] (4) High reliability and convenient maintenance. The device is designed with harsh environments in mind. The panel is made of water-resistant and corrosion-resistant materials, and the air pipe is designed to be flexible, which can adapt to long-term underwater operation, water flow impact and small deformation of the dam body, ensuring the stability of long-term operation. The modular design allows for quick location and independent replacement of individual components (such as sensors and air pumps) if they fail, without the need to dismantle the entire system or carry out large-scale repairs, which greatly reduces the workload of maintenance and long-term operating costs. Attached Figure Description

[0020] Figure 1 This is a front view of the spillway dam's air defense system. Figure 2 A side view of the spillway dam's air defense device; Figure 3 A three-dimensional structural diagram of the spillway dam's air defense device; Figure 4 A schematic diagram of the pressurization module for the overflow dam's air defense device.

[0021] Reference numerals: 1-vent, 2-panel, 3-pressure sensor, 4-vent pipe, 5-jet nozzle, 6-micro air pump, 7-pressurization module. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0023] Example 1 This embodiment provides an anti-cavitation device for overflow dams, such as... Figure 1-4 As shown, it includes: Panel 2 is laid on the surface of the overflow dam, and multiple ventilation holes 1 are provided on panel 2; Pressure sensor 3 is installed on the surface of panel 2 to monitor the pressure of water near panel 2; The booster module 7 is connected to the vent 1; The control module is connected to the pressure sensor 3 and the pressure boosting module 7 respectively, and is used to control the start and stop of the pressure boosting module 7 according to the pressure data monitored by the pressure sensor 3. When the control module detects that the water pressure is lower than a preset threshold, it controls the pressurization module 7 to start, injecting air into the water through the vent 1 to increase the local pressure.

[0024] Example 2 This embodiment provides an anti-cavitation device for overflow dams, such as... Figure 1-4 As shown, it includes: Panel 2 is laid on the surface of the overflow dam, and multiple ventilation holes 1 are provided on panel 2; Pressure sensor 3 is installed on the surface of panel 2 to monitor the pressure of water near panel 2; The booster module 7 is connected to the vent 1; The control module is connected to the pressure sensor 3 and the pressure boosting module 7 respectively, and is used to control the start and stop of the pressure boosting module 7 according to the pressure data monitored by the pressure sensor 3. When the control module detects that the water pressure is lower than a preset threshold, it controls the pressurization module 7 to start, injecting air into the water through the vent 1 to increase the local pressure.

[0025] In a specific embodiment, the booster module 7 includes: Miniature air pump 6, used to generate compressed air; The jet nozzle 5 is connected to the output end of the micro air pump 6, and the outlet end of the jet nozzle 5 is connected to the vent 1. The jet direction and jet flow rate of the jet nozzle 5 are adjustable to adapt to different water flow conditions and dam structures.

[0026] In a specific implementation, the pressurization module 7 is connected to the vent 1 via the vent pipe 4.

[0027] In a specific embodiment, the vent pipe 4 is a flexible vent pipe used to transport compressed air.

[0028] In a specific implementation, the pressure sensor 3 is installed in an area sensitive to changes in water flow pressure.

[0029] In a specific embodiment, the pressure sensor 3 is installed in the middle of the panel 2.

[0030] In a specific implementation, the panel 2 adopts a modular structure, and its size and shape are matched according to the structure of the overflow dam. The material is a water-resistant and corrosion-resistant material.

[0031] In a specific embodiment, the vent holes 1 are arrayed on the panel 2.

[0032] In a specific implementation, the booster module 7 adopts a modular structure, with each booster module 7 connected to a row of vent holes 1 to form an independent monitoring and booster unit.

[0033] In a specific implementation, multiple pressure sensors 3 are provided. The number and distribution density of the pressure sensors 3 can be adjusted according to the complexity of the spillway and the monitoring accuracy requirements.

[0034] The control module employs automated control technology, enabling intelligent control. The device can achieve real-time monitoring, data analysis, and automatic adjustment through the control system to form a water-air mixture, buffering the impact force generated by bubble collapse.

[0035] Components not described in detail in this embodiment are all existing components that can be purchased through public channels.

[0036] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. An anti-cavitation device for spillway dams, characterized in that, include: A panel (2) is laid on the surface of the overflow dam, and multiple ventilation holes (1) are provided on the panel (2). A pressure sensor (3) is installed on the surface of the panel (2) to monitor the pressure of the water near the panel (2); The booster module (7) is connected to the vent (1); The control module is connected to the pressure sensor (3) and the booster module (7) respectively, and is used to control the start and stop of the booster module (7) according to the pressure data monitored by the pressure sensor (3); When the control module detects that the water pressure is lower than a preset threshold, it controls the pressurization module (7) to start and inject air into the water through the vent (1) to increase the local pressure.

2. The overflow dam anti-cavitation device according to claim 1, characterized in that, The booster module (7) includes: Miniature air pump (6) for generating compressed air; The jet head (5) is connected to the output end of the micro air pump (6), and the outlet end of the jet head (5) is connected to the vent (1).

3. The overflow dam anti-cavitation device according to claim 1, characterized in that, The booster module (7) is connected to the vent (1) through the vent pipe (4).

4. The overflow dam anti-cavitation device according to claim 3, characterized in that, The ventilation pipe (4) is a flexible air pipe used to transport compressed air.

5. The overflow dam anti-cavitation device according to claim 1, characterized in that, The pressure sensor (3) is installed in an area sensitive to changes in water pressure.

6. The overflow dam anti-cavitation device according to claim 5, characterized in that, The pressure sensor (3) is installed in the middle of the panel (2).

7. The overflow dam anti-cavitation device according to claim 1, characterized in that, The panel (2) adopts a modular structure, and its size and shape are matched according to the structure of the spillway dam. The material is a water-resistant and corrosion-resistant material.

8. The overflow dam anti-cavitation device according to claim 1, characterized in that, The ventilation holes (1) are arranged in an array on the panel (2).

9. The overflow dam anti-cavitation device according to claim 8, characterized in that, The booster module (7) adopts a modular structure, and each booster module (7) is connected to a row of vents (1) to form an independent monitoring and booster unit.

10. An anti-cavitation device for an overflow dam according to claim 1, characterized in that, The pressure sensor (3) is provided in multiple forms.

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