Compressed air energy storage system air bag test device for simulating underwater environment

Abstract

The invention relates to the field of underwater environment simulation, in particular to a compressed air energy storage system air bag test device for simulating an underwater environment, which comprises a pressure container with an air inlet at one end and an air outlet at the other end; the air hole plate is arranged in the pressure container; the external air bag is arranged in the air hole plate; the test air bag is arranged in the external air bag, and a liquid medium is injected into a gap between the test air bag and the external air bag; the outer flow guide ring is arranged at the air outlet of the pressure container, an outer flow guide channel is formed between the outer flow guide ring and the air outlet of the pressure container, and high-pressure air between the pressure container and the air hole plate flows out of the outer flow guide channel; the inner flow guide ring is arranged on the inner side of the outer flow guide ring, an inner flow guide channel is formed between the inner flow guide ring and the outer flow guide ring, and high-pressure gas between the external air bag and the air hole plate flows out of the inner flow guide channel. The technical problems that the deep sea test cost is high, and a traditional simulation method is difficult to reproduce the water pressure gradient and the water contact environment at the same time are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of underwater environment simulation technology, and in particular to a compressed air energy storage system airbag test device for simulating underwater environments. Background Technology

[0002] Compressed air energy storage technology, as a large-scale, long-term physical energy storage method, has significant advantages such as low environmental impact, long cycle life, and compatibility with multiple energy sources. It has broad application prospects in areas such as renewable energy consumption, grid peak shaving, and emergency backup power. With the global energy structure transitioning towards green and low-carbon development, especially with the deepening of my country's strategic goal of "carbon peaking and carbon neutrality," the installed capacity and grid connection ratio of fluctuating renewable energy sources such as wind and solar power continue to increase, making the demand for safe, efficient, and large-scale energy storage technologies increasingly urgent.

[0003] In recent years, the development of offshore renewable energy has progressed rapidly, especially offshore wind power, which has become an important development direction. Against this backdrop, underwater compressed air energy storage systems have attracted widespread attention due to their ability to directly utilize the deep-sea hydrostatic environment, achieving higher energy density and lower storage costs. Unlike terrestrial compressed air energy storage systems, one of the core characteristics of underwater compressed air energy storage systems is that their storage devices are placed in an underwater environment, subject to hydrostatic pressure and its gradient changes. Flexible airbags, as closed storage containers that can adapt to volume changes, are considered one of the most promising underwater air storage solutions. However, the mechanical behavior, sealing performance, fatigue characteristics, and dynamic response of the airbag materials and structures under complex conditions such as long-term underwater pressure, alternating loads, and immersion in liquid media directly affect the safety and economy of the entire underwater compressed air energy storage system. Therefore, thorough ground-based simulation tests are essential for verification before engineering applications.

[0004] Currently, experimental research on flexible airbags mainly faces the following challenges: First, conducting direct deep-sea real-environment experiments is extremely costly, time-consuming, and risky, and it is difficult to achieve controllable adjustment and repeated observation of parameters; Second, traditional ground simulation methods often use high-pressure water containers to directly apply hydrostatic pressure, but during the simulated airbag deflation (energy release) process, a large amount of high-pressure water needs to be continuously replenished externally to maintain pressure stability, which relies on a high-flow-rate high-pressure water pump system, resulting in complex equipment, high energy consumption and high cost; Third, it is difficult to simultaneously and accurately simulate multiple key elements of the underwater environment, including: (1) the overall high-pressure environment corresponding to the water depth; (2) the pressure gradient along the height of the airbag (pressure changes with depth); (3) the relative stability of the external pressure environment during the airbag inflation and deflation volume change process; (4) the direct contact between the airbag and the liquid medium to examine its material compatibility, permeability and bio-attachment effects under long-term immersion.

[0005] Therefore, there is an urgent need to develop a cost-effective, flexible, and comprehensive testing device that can simulate underwater pressure distribution and water contact environment. This device would be used to conduct comprehensive inflation and deflation characteristic tests, mechanical performance evaluations, and long-term stability studies on flexible airbags used in compressed air energy storage systems under ground laboratory conditions. This would accelerate the research and development process of this technology and reduce the risks associated with its engineering applications. Summary of the Invention

[0006] The present invention aims to overcome the shortcomings of the prior art and provide a compact, cost-controllable, and fully functional airbag test device for simulating underwater environment compressed air energy storage system. It can realistically simulate the pressure environment, pressure gradient and water medium contact conditions when the underwater airbag is working under ground conditions, and provide a reliable test platform for the research and development of underwater flexible air storage devices.

[0007] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A test device for a compressed air energy storage system airbag for simulating an underwater environment, comprising: A pressure vessel is used to provide a high-pressure environment. One end of the pressure vessel is an air inlet that is connected to an external air source, and the other end is an air outlet. A perforated plate is installed inside a pressure vessel, and perforations are provided at different locations on the perforated plate. An external airbag is located inside the perforated plate; high-pressure gas injected into the pressure vessel by an external air source acts on the outer surface of the external airbag through the pores on the perforated plate. The test airbag is placed inside the outer airbag, and the gap between the test airbag and the outer airbag is filled with a liquid medium. An outer guide ring is installed at the outlet of the pressure vessel, forming an outer guide channel between the outer guide ring and the outlet of the pressure vessel. High-pressure gas between the pressure vessel and the orifice plate flows out from the outer guide channel. The inner guide ring is located inside the outer guide ring, forming an inner guide channel between the inner and outer guide rings. High-pressure gas between the outer airbag and the air vent plate flows out through the inner guide channel.

[0008] Furthermore, the perforated plate is a bottle-shaped structure that is closed at one end and open at the other end.

[0009] Furthermore, the bottle mouth end face of the vent plate is fixedly connected to the outer guide ring.

[0010] Furthermore, a pressure sensor is installed on the inner surface of the perforated plate to measure the pressure distribution on the inner surface of the perforated plate.

[0011] Furthermore, a container cover is fitted over the vent of the pressure vessel, and the container cover is threaded or snap-fitted to the vent of the pressure vessel. Vent holes are provided on the container cover at positions corresponding to the inner and outer flow channels, respectively.

[0012] Furthermore, the outer guide ring includes an outer circular ring base plate, and an inner guide ring is disposed in the central hole of the outer circular ring base plate. A first annular guide plate is formed on the inner edge of the outer circular ring base plate, and a second annular guide plate is formed on the outer edge of the outer circular ring base plate. The gap between the second annular guide plate and the outlet of the pressure vessel forms an outer guide channel.

[0013] Furthermore, the inner guide ring includes an inner circular bottom plate, and a third annular guide plate is formed on the outer edge of the inner circular bottom plate. The gap between the third annular guide plate and the first annular guide plate forms an inner guide channel.

[0014] Furthermore, the container lid is provided with slots for engaging the first annular guide plate, the second annular guide plate, and the third annular guide plate.

[0015] Furthermore, the openings of the external airbag and the test airbag pass through the central hole of the inner ring bottom plate and are then fixedly connected to the container lid via flanges.

[0016] Furthermore, a valve is installed in each vent.

[0017] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. This device uses gas pressure to simulate water pressure environment, and combines it with liquid medium to achieve comprehensive simulation of real underwater environment, which greatly reduces test costs and avoids the use of high flow and high pressure water pumps; 2. This device can flexibly simulate the pressure distribution at different water depths and heights by adjusting the inlet pressure and outlet velocity, adapting to various test conditions; 3. This device is equipped with multiple pressure sensors and an adjustment mechanism to achieve dynamic and stable control of the external pressure during the inflation and deflation of the airbag; 4. This device adopts a double airbag structure, and the test airbag is always in contact with water, which can be used to study the long-term stability and durability of airbag materials in aquatic environments. 5. This device has a simple structure and flexible operation, and is suitable for the research and development and performance testing of airbags for underwater compressed air energy storage systems. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1A schematic diagram of the structure of the compressed air energy storage system airbag test device for simulating an underwater environment as described in an embodiment of the present invention; Figure 2 for Figure 1 A partially enlarged structural diagram.

[0019] Explanation of reference numerals in the attached drawings: Pressure vessel 1, Inlet 11, Outlet 12, Orifice plate 2, Orifice 21, Pressure sensor 22, External airbag 3, Test airbag 4, Outer guide ring 5, Outer ring base plate 51, First annular guide plate 52, Second annular guide plate 53, Inner guide ring 6, Inner annular base plate 61, Third annular guide plate 62. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this 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 on this invention. Furthermore, the terms "first," "second," etc., 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, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a 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 will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] like Figure 1 and Figure 2 As shown in the figure, an embodiment of the present invention provides a compressed air energy storage system airbag test device for simulating an underwater environment, comprising, from the outside to the inside, a pressure vessel 1, an orifice plate 2, an outer airbag 3, a test airbag 4, an outer guide ring 5, and an inner guide ring 6 nested together; wherein, the pressure vessel 1 is used to provide a high-pressure environment, one end of the pressure vessel 1 is an air inlet 11 connected to an external air source, and the other end of the pressure vessel 1 is an air outlet 12; the orifice plate 2 is disposed inside the pressure vessel 1, and air holes 21 are opened at different positions on the orifice plate 2; the outer airbag 3 is disposed inside the orifice plate 2; the high-pressure gas injected into the pressure vessel 1 by the external air source passes through the airbag 3. The pores 21 on the orifice plate 2 act on the outer surface of the outer airbag 3; the test airbag 4 is located inside the outer airbag 3, and liquid medium is injected into the gap between the test airbag 4 and the outer airbag 3; the outer guide ring 5 is located at the outlet of the pressure vessel 1, and an outer guide channel (not shown in the figure) is formed between the outer guide ring 5 and the outlet 12 of the pressure vessel 1, and the high-pressure gas between the pressure vessel 1 and the orifice plate 2 flows out from the outer guide channel; the inner guide ring 6 is located inside the outer guide ring 5, and an inner guide channel (not shown in the figure) is formed between the inner guide ring 6 and the outer guide ring 5, and the high-pressure gas between the outer airbag 3 and the orifice plate 2 flows out from the inner guide channel.

[0026] Pressure vessel 1 is a high-pressure resistant cylindrical structure, and its design pressure is not lower than the maximum water depth pressure required for the test. It is usually made of high-strength alloy steel.

[0027] The vent plate 2 is a bottle-shaped structure with one end closed and the other open. The end face of the bottle mouth is fixedly connected to the outer guide ring 5 to secure the vent plate 2. The diameter of the vent plate 2 is smaller than the diameter of the outlet 12 of the pressure vessel 1, allowing the vent plate 2 to enter the interior of the pressure vessel 1. A pressure sensor 21 is installed on the inner surface of the vent plate 2 to measure the pressure distribution on the inner surface of the vent plate 2. A valve is installed in each vent 21 to achieve fine adjustment of the local pressure.

[0028] The outer guide ring 5 includes an outer circular ring base plate 51, and an inner guide ring 6 is disposed in the central hole of the outer circular ring base plate 51. A first annular guide plate 52 is formed on the inner edge of the outer circular ring base plate 51, and a second annular guide plate 52 is formed on the outer edge of the outer circular ring base plate 51. The gap between the second annular guide plate 52 and the outlet 11 of the pressure vessel 1 forms an outer guide channel.

[0029] The inner guide ring 6 includes an inner circular bottom plate 61, and a third annular guide plate 62 is formed on the outer edge of the inner circular bottom plate 61. The gap between the third annular guide plate 62 and the first annular guide plate 51 forms an inner guide channel.

[0030] A container cover (not shown) is fitted over the outlet 11 of the pressure vessel 1. The connection between the container cover and the outlet 11 is a conventional threaded connection or a mechanical snap-fit ​​connection. Exhaust holes are provided on the container cover at positions corresponding to the inner and outer flow channels, allowing high-pressure gas to escape from the container cover. Three slots are provided on the side of the container cover facing the outlet 11, for engaging with the first annular guide plate 51, the second annular guide plate 52, and the third annular guide plate 53 respectively, thus fixing the outer flow guide ring 5 and the inner flow guide ring 6. Another method of fixing the outer flow guide ring 5 and the inner flow guide ring 6 is to connect reinforcing ribs between the third annular guide plate 62 and the first annular guide plate 51, and reinforcing ribs between the first annular guide plate 51 and the outlet 11 of the pressure vessel 1.

[0031] Both the external airbag 3 and the test airbag 4 are made of high-strength, flexible materials, such as reinforced rubber or composite materials. The external airbag 3 has an opening that serves as both its inlet and outlet for liquid, allowing for the injection and discharge of the liquid medium. This opening passes through the central hole of the inner ring base plate 61 and extends to the outside of the container lid, where it is fixedly connected via a flange (not shown). Similarly, the opening of the test airbag 4 (serving as both its inlet and outlet) passes through the central hole of the inner ring base plate 61 and extends to the outside of the container lid, where it is fixedly connected via a flange (not shown).

[0032] The working principle of this device is as follows: During the test preparation phase, the external airbag 3 and the test airbag 4 are installed in place, and the annular space between them is filled with liquid medium until all air is eliminated. An external air source (such as a high-pressure air compressor or air tank) injects high-pressure gas into the pressure vessel 1 through the air inlet 11. After flowing through the air holes 21 on the perforated plate 2, the high-pressure gas flows towards the outer surface of the external airbag 3 in a uniform flow field, applying uniform pressure to the external airbag 3. This pressure is transmitted to the outer surface of the test airbag 4 almost without loss through the incompressible liquid medium. The test airbag 4, surrounded by the liquid medium, bears uniform hydrostatic pressure, realizing the pressure simulation of the test airbag 4 in a deep-water environment.

[0033] During the experiment, pressure sensor 21 monitors the pressure distribution on the outer surface of the external airbag 3 in real time and feeds the data back to the control system. The control system automatically adjusts the total intake pressure to match the target absolute pressure value based on preset simulated water depth parameters. Simultaneously, by adjusting the valve mounted on the air vent near the inner guide channel, the gas flow rate is controlled, establishing and maintaining a pressure gradient along the gas flow direction. This pressure gradient is consistent with the actual static water pressure gradient, thereby simulating water depth pressure changes at different densities.

[0034] During the inflation and energy storage test of the test airbag 4, external compressed air is injected into the test airbag 4 through the inflation / deflation pipeline, causing it to expand. This compresses the liquid medium between the external airbag 3 and the test airbag 4, causing the external airbag 3 to expand accordingly. At this time, the control system detects the real-time pressure change of the pressure sensor 21, dynamically increases the air intake flow rate, and fine-tunes the valve opening to compensate for pressure fluctuations caused by volume changes and maintain a stable external pressure field. Conversely, during the deflation and energy release test of the test airbag 4, its volume contracts, and the control system correspondingly reduces the air intake and adjusts the exhaust to ensure pressure stability. This process effectively simulates an underwater constant pressure environment without the need for a high-flow-rate, high-pressure water pump.

[0035] In the long-term stability test, the test airbag 4 was continuously immersed in the liquid medium. Samples were taken periodically to analyze changes in the composition of the liquid medium, monitor the permeation, dissolution and aging behavior of the airbag material, and evaluate its sealing performance and durability.

[0036] This device can inject liquid media of different densities into the gap between the external airbag 3 and the test airbag 4 to simulate different aquatic environments.

[0037] This device can also be placed horizontally. When the test airbag 4 is in a horizontal state, it can simulate the impact of ocean waves on the test airbag 4.

[0038] This device abandons the design of traditional high-pressure water simulation schemes that rely on high-flow-rate, high-pressure water pumps. Instead, it uses high-pressure gas to create a high-pressure environment, eliminating the need for additional high-power fluid transport equipment and significantly reducing equipment purchase, operation, and maintenance costs. Simultaneously, the device can operate stably in terrestrial environments, avoiding the high transportation costs, complex operating procedures, and uncontrollable environmental risks associated with deep-sea field testing. This meets the high-frequency, low-cost testing requirements of underwater airbag technology development.

[0039] This device can flexibly match the absolute pressure requirements corresponding to different water depths by adjusting the total inlet pressure of the external air source, accurately reproducing the bottom pressure conditions of the underwater airbag in the deep-sea environment. Whether in shallow-sea pilot scenarios or deep-sea energy storage scenarios, multi-condition simulation can be achieved through rapid adjustment of pressure parameters without major modifications to the device structure, thus improving the adaptability and flexibility of the experiment.

[0040] This device allows for precise control of airflow velocity by adjusting the opening of the downstream valve in the internal outflow channel, thereby dynamically adjusting the pressure distribution along the height direction on the surface of the external airbag. This perfectly simulates the pressure gradient differences caused by changes in water depth in water bodies of different densities. This design ensures that the stress on all parts of the test airbag is consistent with the real underwater environment, providing a reliable experimental basis for evaluating the structural stability and stress distribution characteristics during the inflation and deflation process of the airbag.

[0041] This device utilizes multiple pressure sensors arranged on the inner surface of the orifice plate (or the inner wall of the pressure vessel) to monitor the pressure distribution on the surface of the external airbag in real time. When the test airbag expands or contracts during inflation and deflation, the system can automatically or manually adjust the opening of the inlet and outlet valves to dynamically compensate for pressure changes, ensuring that the external pressure of the airbag always meets the underwater constant pressure requirements. If small valves are configured on the orifice plate, fine-tuning of local pressure can be achieved, further improving pressure control accuracy and preventing data distortion due to pressure fluctuations.

[0042] This device employs a nested double-airbag structure, with an external airbag and a test airbag. A liquid medium is filled between the external and test airbags, ensuring the test airbag remains in direct contact with water throughout the process, realistically replicating the underwater working environment. This design not only simulates the physical contact characteristics between the airbag and water but also allows for long-term monitoring of the airbag material's aging, corrosion, and sealing performance degradation in the aquatic environment. It provides crucial testing conditions for evaluating the long-term service life and reliability of underwater airbags, filling a technological gap where terrestrial tests cannot simulate the long-term underwater service environment.

[0043] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0044] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A test device for a compressed air energy storage system airbag for simulating an underwater environment, characterized in that, include: A pressure vessel is used to provide a high-pressure environment. One end of the pressure vessel is an air inlet that is connected to an external air source, and the other end is an air outlet. A perforated plate is installed inside a pressure vessel, and perforations are provided at different locations on the perforated plate. An external airbag is located inside the perforated plate; high-pressure gas injected into the pressure vessel by an external air source acts on the outer surface of the external airbag through the pores on the perforated plate. The test airbag is placed inside the outer airbag, and the gap between the test airbag and the outer airbag is filled with a liquid medium. An outer guide ring is installed at the outlet of the pressure vessel, forming an outer guide channel between the outer guide ring and the outlet of the pressure vessel. High-pressure gas between the pressure vessel and the orifice plate flows out from the outer guide channel. The inner guide ring is located inside the outer guide ring, forming an inner guide channel between the inner and outer guide rings. High-pressure gas between the outer airbag and the air vent plate flows out through the inner guide channel.

2. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 1, characterized in that, The perforated plate is a bottle-shaped structure that is closed at one end and open at the other.

3. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 2, characterized in that, The bottle mouth end face of the vent plate is fixedly connected to the outer guide ring.

4. The compressed air energy storage system airbag test device for simulating an underwater environment according to claim 2 or 3, characterized in that, A pressure sensor is installed on the inner surface of the orifice plate to measure the pressure distribution on the inner surface of the orifice plate.

5. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 1, characterized in that, The pressure vessel is covered with a container cover at the outlet. The container cover is threaded or snapped to the outlet of the pressure vessel. Exhaust holes are provided on the container cover at the positions corresponding to the inner and outer flow channels, respectively.

6. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 5, characterized in that, The outer guide ring includes an outer circular ring base plate, and an inner guide ring is disposed in the central hole of the outer circular ring base plate. A first annular guide plate is formed on the inner edge of the outer circular ring base plate, and a second annular guide plate is formed on the outer edge of the outer circular ring base plate. The gap between the second annular guide plate and the outlet of the pressure vessel forms an outer guide channel.

7. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 6, characterized in that, The inner guide ring includes an inner circular bottom plate, and a third annular guide plate is formed on the outer edge of the inner circular bottom plate. The gap between the third annular guide plate and the first annular guide plate forms an inner guide channel.

8. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 7, characterized in that, The container lid is provided with slots for engaging the first annular guide plate, the second annular guide plate, and the third annular guide plate.

9. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 7, characterized in that, The openings of the external airbag and the test airbag pass through the central hole of the inner ring bottom plate and are then fixedly connected to the container lid via flanges.

10. The compressed air energy storage system airbag test device for simulating underwater environment according to claim 1, characterized in that, A valve is installed in each vent.

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