High-pressure hydrogen leakage accumulation rule testing device in long and narrow limited space

Abstract

The utility model discloses a long and narrow limited space high-pressure hydrogen leakage accumulation rule test device, and belongs to the field of test devices. The upper part of the cross section, perpendicular to the length direction, of the long and narrow limited space model of the device is arch-shaped and the lower part is rectangular; the gas storage automobile model is placed in the long and narrow limited space model; the gas input mechanism is communicated with the high-pressure stirring mechanism; the high-pressure stirring mechanism is communicated with the nozzle; the nozzle is arranged at the position of the gas storage automobile model; the first gas monitoring mechanism and the second gas monitoring mechanism are arranged in a nozzle test gas release area; the plurality of concentration sensors are uniformly distributed at the top of the narrow and long limited space model along the length direction of the narrow and long limited space model and are electrically connected with the data acquisition instrument; an electromagnetic valve is arranged on the first pipeline; the electromagnetic valve and the high-pressure stirring mechanism are electrically connected with the control cabinet; and the control cabinet, the data acquisition instrument, the first gas monitoring mechanism and the second gas monitoring mechanism are electrically connected with the control mechanism. The test result can accurately predict the hydrogen leakage accumulation rule of an actual tunnel scene, the intelligent degree is high, and the cost is low.

Description

Technical Field

[0001] This application relates to the field of experimental equipment technology, and in particular to an experimental device for the law of high-pressure hydrogen leakage and accumulation in a narrow and confined space. Background Technology

[0002] Hydrogen energy, as a clean energy source, plays a crucial role in promoting the transformation of the international energy structure, ensuring energy security, and achieving the global goal of "carbon neutrality." The storage and transportation of hydrogen energy are key links connecting production and application, and are essential for the large-scale commercial application of hydrogen energy.

[0003] Long, narrow, confined spaces such as tunnels are crucial passageways connecting different regions, cities, or road networks, and their safety cannot be ignored. When a hydrogen transport vehicle experiences an accidental leak in a tunnel, the high degree of airtightness and poor ventilation of the tunnel will cause the hydrogen to diffuse and accumulate to varying degrees. Compared to other fuels, colorless and odorless hydrogen leaks are difficult to detect. The leaking hydrogen is affected by the walls, forming an impact jet. The hydrogen rises vertically along the walls and accumulates due to the ceiling, mixing with air to form a flammable hydrogen cloud. Hydrogen has extremely low ignition energy, a wide explosive range, and high heat release during combustion. Once ignited, it will cause a fire or explosion, generating extremely destructive pressure waves and high temperatures, which can easily lead to significant casualties and economic losses, with extremely serious consequences.

[0004] Therefore, understanding the diffusion patterns of hydrogen leakage in narrow, confined spaces such as tunnels, and conducting research on the diffusion and accumulation characteristics of hydrogen leakage in such spaces, will provide a theoretical basis for the promotion of hydrogen energy in my country and have significant practical implications for reducing the risks of hydrogen leakage accidents to transportation and ensuring the safety of narrow, confined spaces.

[0005] Therefore, in response to the major national demand for hydrogen energy development, it is particularly important to explore a highly reliable experimental device that simulates real-world environments and is based on the actual narrow and confined space scenario to study the hydrogen leakage and accumulation patterns. This device is crucial for timely dissipation of flammable gas concentrations in confined spaces and for preventing the occurrence and development of explosion accidents.

[0006] A current confined space hydrogen leakage diffusion test device cannot accurately simulate real-world scenarios, thus the experimental results cannot accurately predict the hydrogen leakage and accumulation patterns in actual narrow and confined spaces such as tunnels. Furthermore, the test device can only be controlled manually or semi-automatically, resulting in a low level of automation. Hydrogen leakage tests pose numerous safety hazards, especially under high-pressure environments, where traditional manual or semi-automatic control cannot monitor and respond to anomalies in real time, easily leading to safety accidents. Utility Model Content

[0007] This application provides a test device for the leakage and accumulation of high-pressure hydrogen in narrow and confined spaces. This device can solve the problems of existing devices being unable to accurately simulate actual scenarios, thus the experimental results cannot accurately predict the hydrogen leakage and accumulation patterns in actual narrow and confined spaces such as tunnels. Furthermore, the test device is manually or semi-automatically controlled, resulting in a low level of intelligence.

[0008] To achieve the above objectives, the technical solution of this utility model embodiment is as follows:

[0009] This utility model provides an experimental device for the leakage and accumulation law of high-pressure hydrogen in a narrow confined space, including a narrow confined space model, a gas input mechanism, a solenoid valve, a control cabinet, a high-pressure stirring mechanism, a nozzle, a first gas monitoring mechanism, a second gas monitoring mechanism, a concentration sensor, a data acquisition instrument, and a control mechanism;

[0010] The upper part of the cross-section of the narrow, confined space model perpendicular to the length direction is arc-shaped, and the lower part is rectangular;

[0011] The gas-storage car model is placed inside the narrow, confined space model.

[0012] The gas input mechanism is connected to the high-pressure stirring mechanism through a first pipeline;

[0013] The high-pressure stirring mechanism is configured to mix tracer particles with the input test gas, and then connect to the nozzle through a second pipeline;

[0014] The nozzle is located at the position of the gas-storage car model;

[0015] Both the first gas monitoring mechanism and the second gas monitoring mechanism are located in the area where the test gas is released from the nozzle. The first gas monitoring mechanism is configured to work in conjunction with the high-pressure stirring mechanism to monitor the distribution law of the diffusion and accumulation flow field after the test gas is released. The second gas monitoring mechanism is configured to monitor the jet structure characteristics of the test gas.

[0016] The concentration sensors are multiple, and the multiple concentration sensors are evenly distributed on the top of the narrow and confined space model along the length direction of the model, and are all electrically connected to the data acquisition instrument.

[0017] The solenoid valve is installed on the first pipeline;

[0018] Both the solenoid valve and the high-pressure stirring mechanism are electrically connected to the control cabinet, which is configured to control the working status of the solenoid valve and the high-pressure stirring mechanism.

[0019] The control cabinet, the data acquisition instrument, the first gas monitoring mechanism, and the second gas monitoring mechanism are all electrically connected to the control mechanism.

[0020] In one possible implementation, the high-pressure stirring mechanism includes a high-pressure stirrer, an inlet valve, a first pressure sensor, an outlet valve, a flow meter, and a second pressure sensor.

[0021] The first pipeline connects the gas input mechanism and the high-pressure stirrer;

[0022] The intake valve and the first pressure sensor are sequentially installed on the first pipeline;

[0023] The second pipeline connects the high-pressure agitator and the nozzle;

[0024] The outlet valve, the flow meter, and the second pressure sensor are sequentially installed on the second pipeline.

[0025] In one possible implementation, the control cabinet includes a data acquisition module, an overload relay, and a first contactor;

[0026] The solenoid valve, the flow meter, the high-pressure stirrer, the overload relay, the first contactor, the first pressure sensor, and the second pressure sensor are all electrically connected to the data acquisition module.

[0027] The data acquisition module is electrically connected to the control mechanism.

[0028] In one possible implementation, the control cabinet further includes an emergency stop button and a second contactor;

[0029] Both the emergency stop button and the second contactor are electrically connected to the data acquisition module.

[0030] In one possible implementation, the experimental device for the accumulation of high-pressure hydrogen in a narrow, confined space also includes a fan and an anemometer.

[0031] The fan is positioned at the top of the narrow, confined space model;

[0032] An anemometer is installed at both ends of the narrow, confined space model.

[0033] In one possible implementation, the first gas monitoring mechanism includes a laser, a sheet light source, a laser reflector, and a first high-speed camera;

[0034] The laser emits laser light;

[0035] The sheet light source is positioned in the output light path of the laser;

[0036] The laser reflector is disposed on the output light path of the sheet light source to change the direction of the laser light path so that the laser is directed towards the area where the test gas is released from the nozzle;

[0037] The first high-speed camera is at least two units, and the at least two first high-speed cameras are configured to capture images of the area where the test gas is released;

[0038] Both of the first high-speed cameras are electrically connected to the control mechanism.

[0039] In one possible implementation, the second gas monitoring mechanism includes a laser light source, a first reflector, a first concave mirror, a second concave mirror, a second reflector, a blade, and a second high-speed camera;

[0040] The first reflector is disposed in the output optical path of the laser source;

[0041] The first concave mirror is disposed in the outgoing light path of the first reflecting mirror;

[0042] The first concave mirror and the second concave mirror are placed symmetrically with respect to the area where the nozzle releases the test gas, and are on the same horizontal plane;

[0043] The second reflector is disposed in the outgoing light path of the second concave mirror;

[0044] The blade is positioned on the outgoing light path of the second reflector;

[0045] The second high-speed camera is positioned on the outgoing light path of the blade.

[0046] The second high-speed camera is electrically connected to the control mechanism.

[0047] In one possible implementation, the test gas is helium;

[0048] The measurement results are corrected using a first formula, which is:

[0049]

[0050] In the formula, Q He This refers to the volumetric flow rate of helium. ρ is the hydrogen volumetric flow rate; air ρ is the gas density in the flow field. He The density of helium; The value represents the hydrogen density; when n = 0, the volumetric flow rate is corrected; when n = 1 / 2, the hydrogen concentration level is corrected; when n = 1, the buoyancy flux is corrected.

[0051] In one possible implementation, the tracer particle is TiO2;

[0052] The method for calculating the diameter of the tracer particle is as follows:

[0053] The exponential decay relationship between the tracer particle velocity and the flow field velocity is calculated using the second formula, which is:

[0054]

[0055] In the formula, U p Let be the velocity of the tracer particle; U be the flow field velocity; t be the tracer particle movement time; and τ be the relaxation time of the limiting particle response, which are calculated using the third formula, which is:

[0056]

[0057] In the formula, ρ p d represents the density of the particles; p The diameter of the particle; μ f Aerodynamic viscosity; C D Re is the drag coefficient; p The Reynolds number of particles is calculated using the fourth formula, which is:

[0058] Re p =(ρ f |U p -U|δ p ) / μ f ,

[0059] In the formula, ρ f For tracer particle density; U p δ represents the velocity of the tracer particle; U represents the flow field velocity; δ represents the velocity of the tracer particle. p The diameter of the tracer particle; μ f It is the aerodynamic viscosity.

[0060] One or more technical solutions provided in the embodiments of this utility model have at least the following technical effects or advantages:

[0061] The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a confined space, as described in this invention, features a confined space model with an arc-shaped upper section and a rectangular lower section in its cross-section perpendicular to its length. The actual size of the confined space is proportionally reduced, and a proportionally reduced gas-storage vehicle model is placed within it. This allows for a highly accurate reconstruction of real confined space scenarios such as tunnels. The experimental results can accurately predict the hydrogen leakage and accumulation patterns in such real confined spaces, providing greater persuasiveness. In this embodiment, the first gas monitoring mechanism works in conjunction with the high-pressure stirring mechanism to monitor the diffusion and accumulation flow field distribution after the test gas is released. The second gas monitoring mechanism monitors the jet structure characteristics of the test gas, ensuring data diversity and accuracy. Multiple concentration sensors measure the electrical signal of the concentration distribution of the leaked test gas within the confined space model over time and transmit this signal to a data acquisition instrument. The second gas monitoring mechanism and multiple concentration sensors provide comprehensive monitoring of the test gas leakage, resulting in more accurate experimental results. The control cabinet and control mechanism are configured such that the control cabinet controls the working status of the solenoid valve and the high-pressure stirring mechanism, and the control cabinet, data acquisition instrument, first gas monitoring mechanism and second gas monitoring mechanism all transmit data to the control mechanism. Thus, the embodiments of the present invention can provide an experimental device with a high degree of intelligence, low cost and safety for studying the accidental release and accumulation law of hydrogen in a narrow and confined space. Attached Figure Description

[0062] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 A schematic diagram of the structure of the experimental device for the law of high-pressure hydrogen leakage and accumulation in a narrow confined space provided in the embodiments of this application;

[0064] Figure 2 The circuit diagram of the control cabinet provided in the embodiments of this application.

[0065] Icons: 1- Narrow confined space model; 2- Gas input mechanism; 21- Gas cylinder; 22- Gas cylinder valve; 23- Main valve; 3- Solenoid valve; 4- Control cabinet; 41- Data acquisition module; 42- Overload relay; 43- First contactor; 44- Emergency stop button; 45- Second contactor; 5- High-pressure stirring mechanism; 51- High-pressure stirrer; 52- Inlet valve; 53- First pressure sensor; 54- Outlet valve; 55- Flow meter; 56- Second pressure sensor; 6- Nozzle; 7-First gas monitoring mechanism; 71-Laser; 72-Sheet light source; 73-Laser reflector; 74-First high-speed camera; 8-Second gas monitoring mechanism; 81-Laser light source; 82-First reflector; 83-First concave mirror; 84-Second concave mirror; 85-Second reflector; 86-Knife edge; 87-Second high-speed camera; 9-Concentration sensor; 10-Data acquisition instrument; 20-Control mechanism; 30-Fan; 40-Anemometer; 50-Gas storage car model. Detailed Implementation

[0066] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0067] In the description of the embodiments of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing the embodiments of this utility model and simplifying the description. They 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 this utility model. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In addition, the terms "installed," "connected," and "linked" 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; they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this utility model can be understood according to the specific circumstances.

[0068] Please refer to Figure 1As shown in the figure, this utility model provides an experimental device for the leakage and accumulation law of high-pressure hydrogen in a narrow confined space, including a narrow confined space model 1, a gas input mechanism 2, a solenoid valve 3, a control cabinet 4, a high-pressure stirring mechanism 5, a nozzle 6, a first gas monitoring mechanism 7, a second gas monitoring mechanism 8, a concentration sensor 9, a data acquisition instrument 10, and a control mechanism 20. The narrow confined space can be a narrow confined space such as a tunnel.

[0069] The narrow, confined space model 1 has an arc-shaped upper section and a rectangular lower section perpendicular to its length. This design more closely resembles the shape of a real tunnel, accurately reflecting the diffusion and accumulation patterns of leaked test gas, while also reducing cost. The arc is formed by a chord and its corresponding arc. A chord is a line segment connecting any two points on a circle, while an arc is a curve on a circle. When the chord and its corresponding arc are combined, an arc is formed. This narrow, confined space model 1 is made of acrylic material, which is highly malleable, has high visibility, excellent sealing performance, and is cost-effective.

[0070] A gas-storage vehicle model 50 is placed within a narrow, confined space model 1. Placing the gas-storage vehicle model 50 within the narrow, confined space model 1 more realistically simulates confined space scenarios such as tunnels where gas leaks occur. Using a scaled-down version of the narrow, confined space model 1, and housing the scaled-down gas-storage vehicle model 50, significantly enhances the credibility and persuasiveness of the experimental results. For example, this gas-storage vehicle model 50 could be a hydrogen-storage riding model.

[0071] The gas input mechanism 2 is connected to the high-pressure stirring mechanism 5 via the first pipeline. For example... Figure 1 As shown, the gas input mechanism 2 includes multiple gas cylinders 21, multiple gas cylinder valves 22, and a main valve 23. Each gas cylinder 21 is equipped with a gas cylinder valve 22, and the ends of the multiple gas cylinder valves 22 facing away from the gas cylinders 21 are all connected to one end of the main valve 23. The other end of the main valve 23 is connected to a solenoid valve 3. The opening and closing state of the corresponding gas cylinder 21 can be independently controlled through the gas cylinder valve 22, thereby controlling whether the gas cylinder 21 outputs test gas. The opening and closing state of all gas cylinders 21 can be controlled through the main valve 23, thereby controlling whether all gas cylinders 21 output test gas. The gas cylinder valves 22 and the main valve 23 ensure the controllability of the gas source during the test. Figure 1 A schematic diagram of a gas input mechanism 2 is shown, which consists of six high-pressure helium cylinders 21 with a capacity of 40L, a pressure of 14±0.5MPa, and a purity of 99.999% connected in parallel. Helium is used instead of hydrogen as the test gas source to simulate a hydrogen leak scenario and ensure the safety of the test.

[0072] The high-pressure stirring mechanism 5 is configured to mix the tracer particles with the input test gas, and then connect to the nozzle 6 via a second pipeline. The nozzle 6 is located at the position of the gas-storage vehicle model 50, and releases the test gas into the narrow, confined space model 1 through the nozzle 6 to simulate the environment of high-pressure test gas leakage at different locations within the narrow, confined space model 1. Figure 1 A schematic diagram of a structure with at least three nozzles 6 is shown. The at least three nozzles 6 are evenly distributed around the compartment of the gas-storage vehicle model 50 to better simulate a real gas leak scenario. The position of the nozzles 6 extending into the narrow, confined space model 1 can be adjusted to realistically simulate a gas leak.

[0073] The first gas monitoring mechanism 7 and the second gas monitoring mechanism 8 are both located in the area where the test gas is released from the nozzle 6. The first gas monitoring mechanism 7 is configured to work in conjunction with the high-pressure stirring mechanism 5 to monitor the distribution law of the diffusion and accumulation flow field after the test gas is released. The second gas monitoring mechanism 8 is configured to monitor the jet structure characteristics of the test gas.

[0074] Multiple concentration sensors 9 are evenly distributed along the length of the narrow, confined space model 1 at the top of the model 1, thus forming a structure as follows: Figure 1 The linear array layout shown has multiple concentration sensors 9 electrically connected to the data acquisition instrument 10 to form a concentration sensor network, which is used to collect the leakage test gas concentration signal in a certain area of ​​the narrow confined space model 1.

[0075] A solenoid valve 3 is installed on the first pipeline. Both the solenoid valve 3 and the high-pressure stirring mechanism 5 are electrically connected to the control cabinet 4, which is configured to control the operating status of the solenoid valve 3 and the high-pressure stirring mechanism 5. The control cabinet 4, the data acquisition instrument 10, the first gas monitoring mechanism 7, and the second gas monitoring mechanism 8 are all electrically connected to the control mechanism 20.

[0076] The concentration sensor 9 is electrically connected to the data acquisition unit 10, and the data acquisition unit 10 is electrically connected to the control mechanism 20. The control mechanism 20 can control the data acquisition duration of the concentration sensor 9. The control mechanism 20 can be a computer.

[0077] Solenoid valve 3 is electrically connected to control cabinet 4, and control cabinet 4 is electrically connected to control mechanism 20. Control mechanism 20 can control solenoid valve 3 to automatically open or close, thereby controlling the gas input mechanism 2 to start or stop supplying gas, achieving precise control of the test process. Control mechanism 20 can also control the opening duration of solenoid valve 3, thereby setting the test gas leakage duration.

[0078] The control cabinet 4 and control mechanism 20 of this utility model embodiment ensure safety during the test process through automated processes and real-time monitoring, reduce the risk of test gas leakage, improve the reliability of the test, and provide a higher level of safety assurance for operators, which is a major innovation in terms of safety.

[0079] The experimental apparatus for testing the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to this invention features a narrow, confined space model 1 with an arc-shaped upper section and a rectangular lower section in its cross-section perpendicular to its length. The actual size of the narrow, confined space is proportionally reduced, and a proportionally reduced gas-storage vehicle model 50 is placed inside the narrow, confined space model 1. This allows for a highly accurate reproduction of real narrow, confined space scenarios such as tunnels. The experimental results can accurately predict the hydrogen leakage and accumulation patterns in real narrow, confined space scenarios such as tunnels, providing greater persuasiveness. In this embodiment, the first gas monitoring mechanism 7 works in conjunction with the high-pressure stirring mechanism 5 to monitor the diffusion and accumulation flow field distribution patterns after the release of the test gas. The second gas monitoring mechanism 8 monitors the jet structure characteristics of the test gas, ensuring data diversity and accuracy. Multiple concentration sensors 9 measure the electrical signal of the concentration distribution of the leaked test gas within the narrow, confined space model 1 over time and transmit this electrical signal to the data acquisition instrument 10. The second gas monitoring mechanism 8 and multiple concentration sensors 9 monitor the test gas leakage from multiple perspectives, resulting in more accurate experimental results. The control cabinet 4 and the control mechanism 20 are configured such that the control cabinet 4 controls the working status of the solenoid valve 3 and the high-pressure stirring mechanism 5. The control cabinet 4, the data acquisition instrument 10, the first gas monitoring mechanism 7 and the second gas monitoring mechanism 8 all transmit data to the control mechanism 20. Thus, the present invention can provide a highly intelligent, low-cost and safe experimental device for studying the accidental release and accumulation of hydrogen in a narrow and confined space.

[0080] like Figure 1 As shown, the high-pressure stirring mechanism 5 includes a high-pressure stirrer 51, an inlet valve 52, a first pressure sensor 53, an outlet valve 54, a flow meter 55, and a second pressure sensor 56. A first pipeline connects the gas input mechanism 2 and the high-pressure stirrer 51. The inlet valve 52 and the first pressure sensor 53 are sequentially arranged on the first pipeline. That is, a solenoid valve 3, an inlet valve 52, and a first pressure sensor 53 are sequentially arranged on the first pipeline along the direction from the gas input mechanism 2 to the high-pressure stirrer 51. A second pipeline connects the high-pressure stirrer 51 and the nozzle 6. The outlet valve 54, the flow meter 55, and the second pressure sensor 56 are sequentially arranged on the second pipeline. The high-pressure stirring mechanism 5 of this embodiment can achieve uniform mixing of the test gas and tracer particles.

[0081] The high-pressure stirrer 51 can be a high-pressure stirring device with model number 024-73210001 produced by Kaiyuan Chemical Machinery Manufacturing Co., Ltd., used to mix the injected high-pressure test gas and small-diameter tracer particles evenly, and used to monitor test gas leakage with the first gas monitoring agency 7, analyze the diffusion and accumulation flow field distribution law after the release of high-pressure test gas, and ensure the accuracy of test data.

[0082] The flow meter 55 can be a gas rotor flow meter. The gas flow rate in the second pipeline can be adjusted and monitored through the flow meter 55 to ensure the consistency of test conditions.

[0083] The airtightness of the gas supply mechanism (gas input mechanism 2 and high-pressure stirring mechanism 5) can be checked through control cabinet 4. Open the main valve 23, any one of the gas cylinder valves 22 (only one gas cylinder valve 22 is opened at a time), the inlet valve 52, and the outlet valve 54. Control cabinet 4 is controlled by control mechanism 20, which in turn controls the start solenoid valve 3. The high-pressure test gas in gas cylinder 21 is transported through the first pipeline, flowing sequentially through inlet valve 52, first pressure sensor 53, and into high-pressure stirrer 51. After exiting outlet valve 54, the flow rate is controlled by flow meter 55, and finally flows through second pressure sensor 56. The operator observes the pressure values ​​displayed by first pressure sensor 53 and second pressure sensor 56, calculates the error, and monitors the pressure changes within the gas supply mechanism to determine the airtightness of the entire gas supply mechanism. If the error is less than 5%, the gas supply mechanism is considered leak-free; if the error is greater than 5%, the gas supply mechanism is considered leaking.

[0084] like Figure 2 As shown, the control cabinet 4 includes a data acquisition module 41, an overload relay 42, and a first contactor 43. The data acquisition module 41 can be an I08R-A model data acquisition module.

[0085] Solenoid valve 3, flow meter 55, high-pressure stirrer 51, overload relay 42, first contactor 43, first pressure sensor 53, and second pressure sensor 56 are all electrically connected to data acquisition module 41. Data acquisition module 41 is electrically connected to control mechanism 20.

[0086] The flowmeter 55 has 485+ and 485- interfaces for communication, which are electrically connected to contacts A and B of the data acquisition module 41, respectively. This enables the transmission of the test gas flow rate information measured by the flowmeter 55 to the data acquisition module 41, and then to the control mechanism 20. The control mechanism 20 records the data through its program operation, and the action commands are transmitted to the data acquisition module 41 of the control cabinet 4 via a network cable. The data acquisition module 41 sends an electrical signal indicating the test gas flow rate passing through the flowmeter 55 through contacts A and B. The flowmeter 55 then outputs the collected data to the control mechanism 20 via the network cable.

[0087] 3:A refers to the configuration of the serial communication port (COM port) on the host, indicating that COM3 port is assigned to device A. 8:B refers to the configuration of the serial communication port (COM port) on the host, indicating that COM8 port is assigned to device B.

[0088] Overload relay 42 is electrically connected to the IN2 interface of data acquisition module 41. IN2 corresponds to the OUT2 output terminal, which is electrically connected to the first contactor 43. A green indicator light H is connected in parallel to the first contactor 43. When the test device is working normally, overload relay 42 is activated. When overload protection of overload relay 42 is activated, the first contactor 43 is de-energized, and a stop signal is output through OUT2, stopping the high-pressure stirrer 51. IN1 and IN2 represent switching quantities.

[0089] The first pressure sensor 53 is electrically connected to I1 of the data acquisition module 41, and the second pressure sensor 56 is electrically connected to I2 of the data acquisition module 41. I1 and I2 represent analog quantities. The first pressure sensor 53 and the second pressure sensor 56 are electrically connected to the analog quantity channels I1 and I2 of the data acquisition module 41, respectively. When the test device starts operating, the first pressure sensor 53 and the second pressure sensor 56 input pressure and current signals to the data acquisition module 41 through I1 and I2, respectively. The data acquisition module 41 converts the electrical signals into data signals and transmits them to the control mechanism 20 via a network cable.

[0090] The data acquisition module 41 has its 4M port and port I4 connected to the high-pressure stirrer 51 to control the speed of the high-pressure stirrer 51, where 4M is a reference value.

[0091] The control cabinet 4 in this embodiment enhances the intelligence and automation level of the testing device. This embodiment introduces an automatic control mechanism for high-pressure test gas leakage, including a solenoid valve 3 and a flow meter 55. This mechanism enables automatic detection of the airtightness of the gas supply mechanism, precise control and automatic shutdown of gas leaks, and comprehensive, real-time monitoring and early warning of the testing device's safety, significantly improving the automation and intelligence level of the experiment. Compared with existing manual or semi-automatic technologies, the automatic control mechanism of this invention greatly reduces human error in experimental operations, improves experimental efficiency and data consistency, and also reduces the operational burden on experimental personnel.

[0092] At the start of the test, the experimenter manually inputs the upper limit pressure of 0.2 MPa into the air circuit mechanism through the program of the control mechanism 20. After the test starts, when the pressure value monitored by the first pressure sensor 53 exceeds 3 MPa, the solenoid valve 3 closes, the test device stops working, and the air supply mechanism stops supplying air.

[0093] Continue to refer to Figure 2 As shown, the control cabinet 4 also includes an emergency stop button 44 and a second contactor 45. Both the emergency stop button 44 and the second contactor 45 are electrically connected to the data acquisition module 41. Of course, the control cabinet 4 also includes a cabinet body, and the data acquisition module 41, overload relay 42, first contactor 43, emergency stop button 44 and second contactor 45 are all located in the cabinet body.

[0094] like Figure 2 As shown, the emergency stop button 44 is connected to the IN1 interface of the data acquisition module 41. IN1 corresponds to OUT1, and OUT1 is connected to the first contactor 43. When the emergency stop button 44 is pressed by the program control, the signal is output through OUT1, the line is disconnected, the first contactor 43 is de-energized, and the test device stops working, thereby ensuring the safety of the test device.

[0095] Furthermore, such as Figure 1 As shown, the experimental apparatus for the accumulation of high-pressure hydrogen gas in a narrow, confined space also includes a fan 30 and an anemometer 40. The fan 30 is located at the top of the narrow, confined space model 1. An anemometer 40 is installed at both ends of the narrow, confined space model 1. The fan 30 can be a blower. The fan 30 is turned on to dilute the test gas released in the narrow, confined space model 1, completing the environmental simulation of ventilation along the length of the narrow, confined space model 1. The fan 30, anemometer 40, and multiple concentration sensors 9 are used simultaneously. The anemometer 40 collects and records the wind speed data inside the narrow, confined space model 1, and the concentration sensors 9 collect the electrical signals of the concentration distribution inside the narrow, confined space model 1, thereby enabling the analysis of the dilution effect of longitudinal ventilation on the gas.

[0096] like Figure 1 As shown, the first gas monitoring mechanism 7 includes a laser 71, a sheet light source 72, a laser reflector 73, and a first high-speed camera 74.

[0097] Laser 71 emits laser light. A sheet light source 72 is positioned in the output light path of laser 71. A laser reflector 73 is positioned in the output light path of sheet light source 72 to change the direction of the laser beam, directing the laser towards the area where the test gas is released from nozzle 6. At least two first high-speed cameras 74 are configured to capture images of the area where the test gas is released. Both first high-speed cameras 74 are electrically connected to control mechanism 20 (not shown in the figure).

[0098] Specifically, after the experiment begins, nano-sized TiO2 particles are injected into the high-pressure stirring mechanism 5 as tracer particles. When the test gas in the gas cylinder 21 is injected into the high-pressure stirring mechanism 5 through the first pipeline, the tracer particles are mixed evenly with the test gas in the high-pressure stirring mechanism 5, and then released into the narrow confined space model 1 along with the test gas through the second pipeline. The laser 71 is turned on to emit laser light. A sheet light source 72 is placed in the output optical path of the laser 71, and the laser beam forms a thin and uniform light sheet through the sheet light source 72. A laser reflector 73 is placed in the output optical path of the sheet light source 72 to change the direction of the laser beam so that the laser is directed towards the area where the test gas is released from the nozzle 6, illuminating the fluid area containing the tracer particles. At least two first high-speed cameras 74 are configured to capture images of the area where the test gas is released. Figure 1 The experiment demonstrates the acquisition of two-dimensional images using two first high-speed cameras 74 with an exposure time interval of up to 140 ns. The two first high-speed cameras 74 transmit the image data to the control mechanism 20, which performs image processing on the image data, calculates the average displacement of particles within the shooting area, calculates the velocity vector of the fluid by combining the known shooting time interval, repeatedly shoots and records the flow field distribution images at different locations, and then combines the velocity vectors at all locations to form the velocity field of the entire observation area. Finally, the velocity field data is analyzed to monitor the diffusion and accumulation distribution patterns of the experimental gas after release (quantitatively).

[0099] The second gas monitoring device 8 includes a laser light source 81, a first reflector 82, a first concave mirror 83, a second concave mirror 84, a second reflector 85, a blade 86, and a second high-speed camera 87.

[0100] A first reflector 82 is disposed on the output light path of the laser source 81. A first concave mirror 83 is disposed on the output light path of the first reflector 82. The first concave mirror 83 and the second concave mirror 84 are symmetrically placed with respect to the area where the test gas is released from the nozzle 6, and are on the same horizontal plane. A second reflector 85 is disposed on the output light path of the second concave mirror 84. A knife edge 86 is disposed on the output light path of the second reflector 85. A second high-speed camera 87 is disposed on the output light path of the knife edge 86. The second high-speed camera 87 is electrically connected to the control mechanism 20.

[0101] Specifically, the laser source 81 is turned on first. A first reflecting mirror 82 is set in the output light path of the laser source 81, and the first reflecting mirror 82 is adjusted to collect and focus the beam. A first concave mirror 83 is set in the output light path of the first reflecting mirror 82 to reflect the beam to the first concave mirror 83. The first concave mirror 83 and the second concave mirror 84 are placed symmetrically with respect to the area where the test gas is released from the nozzle 6, and are on the same horizontal plane. A second reflecting mirror 85 is set in the output light path of the second concave mirror 84, and the second reflecting mirror is adjusted to ensure that the focused beam is collected. A knife edge 86 is set in the output light path of the second reflecting mirror 85, and a second high-speed camera 87 is set in the output light path of the knife edge 86. The knife edge 86 is adjusted to change the brightness of the on-site image, ensuring that the second high-speed camera 87 collects higher quality flow field distribution image information. The second high-speed camera 87 transmits the image information to the control mechanism 20, thereby recording the density change of the gas flow field near the nozzle 6, and thus monitoring the jet structure characteristics (qualitative) of the test gas.

[0102] The first gas monitoring mechanism 7 of this embodiment can quantitatively analyze the diffusion and accumulation flow field distribution after the release of the test gas, while the second gas monitoring mechanism 8 can qualitatively analyze the jet structure characteristics of the test gas. This ensures the diversity and accuracy of the data. By combining image data with text data, the distribution law of the diffusion and accumulation flow field after the accidental release of the test gas, as well as the jet structure characteristics of the test gas, are obtained. The multi-source data acquisition strategy significantly improves the richness and reliability of the experimental data, which helps to more comprehensively understand and predict hydrogen leakage phenomena. Furthermore, the integration of a concentration sensor 9 and an anemometer 40 enables comprehensive capture of concentration and velocity data within the narrow, confined space model 1, providing a detailed data foundation for in-depth analysis of hydrogen diffusion and accumulation characteristics.

[0103] Optionally, helium is used as the test gas to ensure safety. Due to the differences between hydrogen and helium, the measurement results are corrected using the first formula to ensure accuracy. The first formula is:

[0104]

[0105] In the formula, Q He This refers to the volumetric flow rate of helium. ρ is the hydrogen volumetric flow rate; air ρ is the gas density in the flow field. He The density of helium; For hydrogen density; when n = 0, correct for volumetric flow rate; when n = 1 / 2, correct for hydrogen concentration level; when n = 1, correct for buoyancy flux.

[0106] Helium is a gaseous flow field, and the density of tracer particles should be as equal as possible to the density of the fluid. To ensure imaging, the particle diameter should be as small as possible. Therefore, TiO2 particles were chosen as tracer particles to ensure the effectiveness and accuracy of the experimental device.

[0107] Optionally, the tracer particles are TiO2. The diameter of the tracer particles is calculated as follows:

[0108] Based on the Basset-Boussinesq-Oseen (BBO) equations, considering only the viscous and inertial terms, the exponential decay relationship between the tracer particle velocity and the flow field velocity is calculated using the second formula:

[0109]

[0110] In the formula, U p U is the velocity of the tracer particle; U is the flow field velocity; t is the tracer particle's movement time; τ is the relaxation time of the constrained particle response, calculated using the third formula, which is:

[0111]

[0112] In the formula, ρ p d represents the density of the particles; p The diameter of the particle; μ f Aerodynamic viscosity; C D Re is the drag coefficient; p The Reynolds number of particles is calculated using the fourth formula, which is:

[0113] Re p =(ρ f U p -Uδ p ) / μ f ,

[0114] In the formula, ρ f For tracer particle density; U p δ represents the velocity of the tracer particle; U represents the flow field velocity; δ represents the velocity of the tracer particle. p The diameter of the tracer particle; μ f It is the aerodynamic viscosity.

[0115] Furthermore, the diameter of the tracer particles is 5µm to 20µm. To adapt to the monitoring effect under different working conditions, small-diameter TiO2 particles (5µm to 20µm) were selected as tracer particles for monitoring.

[0116] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, please refer to each other. Each embodiment focuses on describing the differences from other embodiments.

[0117] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.

Claims

1. An experimental device for investigating the accumulation and leakage of high-pressure hydrogen in a narrow, confined space, characterized in that, It includes a narrow, confined space model, a gas input mechanism, a solenoid valve, a control cabinet, a high-pressure stirring mechanism, a nozzle, a first gas monitoring mechanism, a second gas monitoring mechanism, a concentration sensor, a data acquisition instrument, and a control mechanism; The upper part of the cross-section of the narrow, confined space model perpendicular to the length direction is arc-shaped, and the lower part is rectangular; The gas-storage car model is placed inside the narrow, confined space model; The gas input mechanism is connected to the high-pressure stirring mechanism through a first pipeline; The high-pressure stirring mechanism is configured to mix tracer particles with the input test gas, and then connect to the nozzle through a second pipeline; The nozzle is located at the position of the gas-storage car model; Both the first gas monitoring mechanism and the second gas monitoring mechanism are located in the area where the test gas is released from the nozzle. The first gas monitoring mechanism is configured to work in conjunction with the high-pressure stirring mechanism to monitor the distribution law of the diffusion and accumulation flow field after the test gas is released. The second gas monitoring mechanism is configured to monitor the jet structure characteristics of the test gas. The concentration sensors are multiple, and the multiple concentration sensors are evenly distributed on the top of the narrow and confined space model along the length direction of the model, and are all electrically connected to the data acquisition instrument. The solenoid valve is installed on the first pipeline; Both the solenoid valve and the high-pressure stirring mechanism are electrically connected to the control cabinet, which is configured to control the working status of the solenoid valve and the high-pressure stirring mechanism. The control cabinet, the data acquisition instrument, the first gas monitoring mechanism, and the second gas monitoring mechanism are all electrically connected to the control mechanism.

2. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to claim 1, characterized in that, The high-pressure stirring mechanism includes a high-pressure stirrer, an inlet valve, a first pressure sensor, an outlet valve, a flow meter, and a second pressure sensor. The first pipeline connects the gas input mechanism and the high-pressure stirrer; The intake valve and the first pressure sensor are sequentially installed on the first pipeline; The second pipeline connects the high-pressure agitator and the nozzle; The outlet valve, the flow meter, and the second pressure sensor are sequentially installed on the second pipeline.

3. The experimental apparatus for testing the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to claim 2, characterized in that, The control cabinet includes a data acquisition module, an overload relay, and a first contactor; The solenoid valve, the flow meter, the high-pressure stirrer, the overload relay, the first contactor, the first pressure sensor, and the second pressure sensor are all electrically connected to the data acquisition module. The data acquisition module is electrically connected to the control mechanism.

4. The experimental apparatus for testing the accumulation law of high-pressure hydrogen leakage in a narrow confined space according to claim 3, characterized in that, The control cabinet also includes an emergency stop button and a second contactor; Both the emergency stop button and the second contactor are electrically connected to the data acquisition module.

5. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to claim 1, characterized in that, It also includes fans and anemometers; The fan is positioned at the top of the narrow, confined space model; An anemometer is installed at both ends of the narrow, confined space model.

6. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a confined space according to any one of claims 1 to 5, characterized in that, The first gas monitoring device includes a laser, a sheet light source, a laser reflector, and a first high-speed camera; The laser emits laser light; The sheet light source is positioned in the output light path of the laser; The laser reflector is disposed on the output light path of the sheet light source to change the direction of the laser light path so that the laser is directed towards the area where the test gas is released from the nozzle; The first high-speed camera is at least two units, and the at least two first high-speed cameras are configured to capture images of the area where the test gas is released; Both of the first high-speed cameras are electrically connected to the control mechanism.

7. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a confined space according to any one of claims 1 to 5, characterized in that, The second gas monitoring mechanism includes a laser light source, a first reflector, a first concave mirror, a second concave mirror, a second reflector, a blade, and a second high-speed camera; The first reflector is disposed in the output optical path of the laser source; The first concave mirror is disposed in the outgoing light path of the first reflecting mirror; The first concave mirror and the second concave mirror are placed symmetrically with respect to the area where the nozzle releases the test gas, and are on the same horizontal plane; The second reflector is disposed in the outgoing light path of the second concave mirror; The blade is positioned on the outgoing light path of the second reflector; The second high-speed camera is positioned on the outgoing light path of the blade. The second high-speed camera is electrically connected to the control mechanism.

8. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to claim 1, characterized in that, The test gas was helium; The measurement results are corrected using a first formula, which is: In the formula, Q He This refers to the volumetric flow rate of helium. ρ is the hydrogen volumetric flow rate; air ρ is the gas density in the flow field. He The density of helium; The value represents the hydrogen density; when n = 0, the volumetric flow rate is corrected; when n = 1 / 2, the hydrogen concentration level is corrected; when n = 1, the buoyancy flux is corrected.

9. The experimental apparatus for investigating the accumulation and leakage of high-pressure hydrogen in a narrow, confined space according to claim 8, characterized in that, The tracer particle is TiO2; The method for calculating the diameter of the tracer particle is as follows: The exponential decay relationship between the tracer particle velocity and the flow field velocity is calculated using the second formula, which is: In the formula, U p Let be the velocity of the tracer particle; U be the flow field velocity; t be the tracer particle movement time; and τ be the relaxation time of the limiting particle response, calculated using the third formula, which is: In the formula, ρ p d represents the density of the particles; p The diameter of the particle is μ. f C is the aerodynamic viscosity. D Re is the drag coefficient; p The Reynolds number of particles is calculated using the fourth formula, which is: Re p =(ρ f U p -Uδ p ) / m f , In the formula, ρ f For tracer particle density; U p δ represents the velocity of the tracer particle; U represents the flow field velocity; p The diameter of the tracer particle; μ f It is the aerodynamic viscosity.

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