A high-pressure flammable gas leakage jet fire simulation test device and method

Abstract

The application discloses a high-pressure combustible gas leakage jet fire simulation test device and method, which comprises a combustible gas cylinder, a nitrogen cylinder, a pressure reducing valve, a busbar, a high-pressure needle valve, a booster, an air compressor, an electromagnetic valve, a high-pressure buffer gas cylinder, a high-pressure hose, a high-pressure storage tank, a pressure sensor, a flame detector, a heat flow meter, a thermocouple, a high-speed camera and a data acquisition instrument. The device can be used for studying the influence law of different combustible gas types, leakage pressures (up to 70 MPa), ignition modes (spontaneous ignition and artificial ignition), nozzle structure sizes, external environments and other factors on the behavior characteristics and kinetic parameters of high-pressure jet flames, including ignition mechanism, flame suspension and blowout instability, flame shape (length, width and inclination angle), flame microstructure and dynamics, temperature and flame thermal radiation, so as to obtain the critical conditions for forming stable jet flames. The application can carry out tests on high-pressure combustible gas leakage jet fires under different conditions.

Description

Technical Field

[0001] This invention belongs to the field of flammable gas safety technology, specifically relating to a high-pressure flammable gas leak jet fire simulation test device and method. Background Technology

[0002] Currently, the storage of combustible gases mainly includes high-pressure gaseous storage and liquid storage. Among these, high-pressure gaseous storage, as an economical and efficient energy storage method, is widely used in chemical production, new energy vehicles, and energy storage. However, due to structural fatigue of equipment and pipelines, aging of connections, or other reasons, combustible gases may leak unexpectedly. Leaked combustible gases can spontaneously combustible (such as hydrogen) or, under the influence of external ignition sources, can easily cause fires and explosions. Jet fire is a typical hazard form in high-pressure combustible gas leak fires and explosions. How to accurately assess the hazards of jet fire is a major research topic that should be focused on in current industrial safety. Domestic and foreign scholars have conducted extensive research on the spontaneous combustion and jet fire characteristics of combustible gas leaks in the medium and high pressure range (<30MPa), and have obtained many valuable research results. However, due to limitations in experimental techniques, previous research on the safety aspects of spontaneous combustion and jet fire in high-pressure (35–70 MPa) combustible gas leaks has been largely ineffective. In particular, high-pressure jet fire exhibits highly turbulent and large-scale combustion characteristics, and is prone to causing more complex and severe thermal radiation hazards, posing a new challenge to the field of high-pressure combustible gas safety research. Therefore, establishing a high-pressure combustible gas leak jet fire simulation test device to study high-pressure combustible gas leaks under different operating conditions and to establish a quantitative model of the jet flame geometry and thermal radiation characteristics will not only help deepen the research on the behavioral characteristics and dynamic properties of high-pressure jet fire, but also provide experimental conditions for the prediction and early warning of high-pressure combustible gas leak disasters, the development of safety control technologies, and the formulation of relevant safety standards and specifications. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a high-pressure flammable gas leak jet fire simulation test device and method, which can conduct experimental research on high-pressure flammable gas leak jet fire under different conditions.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A high-pressure combustible gas leak jet fire simulation test device is disclosed. The entire test device includes a gas supply system, a gas pressurization and buffering system, a high-pressure storage tank and downstream pipeline system, an ignition control system, a data acquisition system, a dynamic image recording system, a flame characteristic parameter measurement system, and a solenoid valve control system. The gas supply system provides a continuous and stable gas source to the gas pressurization and buffering system, and also provides a gas source for pre-test airtightness testing and post-test purging of the device. The gas pressurization and buffering system includes a combustible gas booster and a high-pressure gas buffer tank, mainly used for pressurizing and storing medium and low-pressure gases, and can provide a continuous wide pressure range (1-70 MPa) gas to the high-pressure storage tank as needed. The high-pressure storage tank and downstream pipeline system consists of a high-pressure storage tank and downstream pipelines. When the ignition method is spontaneous combustion, the downstream pipeline includes rupture discs, gaskets / pressure rings, pipe clamps, and metal pipes; when artificial ignition is used, the downstream pipeline includes solenoid valves and pipe... The test setup includes a clamp and metal pipes; an ignition control system comprising an igniter and an ignition controller, providing different ignition methods; a data acquisition system that records pressure changes in the high-pressure storage tank, pressure changes in the downstream pipeline, light signal changes, and changes in parameters such as temperature and heat flow, and can input trigger signals to a dynamic image recording system; a dynamic image recording system for recording the propagation of spontaneous combustion flames in the downstream pipeline, the gas jet at the pipe opening, and the dynamic development process of the jet flame; a flame characteristic parameter measurement system for measuring temperature changes along the jet flame axis and its surroundings, and changes in flame thermal radiation; and a solenoid valve control system that controls the opening and closing of the solenoid valves in the test setup.

[0006] Furthermore, the gas supply system mainly consists of a high-pressure test gas cylinder group, a nitrogen cylinder, a first pressure reducing valve, a second pressure reducing valve, a third pressure reducing valve, a fourth pressure reducing valve, a fifth pressure reducing valve, a manifold, a first high-pressure needle valve, and a first check valve. The high-pressure test gas cylinder group can be used individually or in combination according to the pressure inside the cylinder and the test pressure requirements. The high-pressure test gas cylinder group is connected to the manifold through the first, second, and third pressure reducing valves. Similarly, the nitrogen cylinder is connected to the manifold through the fourth pressure reducing valve. The fifth pressure reducing valve is used to display the gas pressure inside the pipeline and control the gas supply pressure to the test pipeline. When replacing the cylinder, the pipeline needs to be purged. At this time, the first high-pressure needle valve is opened and the fifth pressure reducing valve is closed to purge the pipeline. The first check valve is mainly used to ensure one-way gas flow.

[0007] Furthermore, the gas pressurization and buffering system mainly consists of an air compressor, a gas booster, a safety relief valve, a first vent pipe, a second vent pipe, a second high-pressure needle valve, a third high-pressure needle valve, a first solenoid valve, a second solenoid valve, a first vacuum pump, a pressure gauge, and a high-pressure gas buffer tank. The air compressor provides drive to the gas booster through the drive gas inlet. The gas supplied by the gas supply system enters the booster through the low-pressure gas inlet for pressurization. After pressurization, the gas enters the high-pressure gas buffer tank for temporary storage through the high-pressure gas outlet. The safety relief port is connected to the safety relief valve and the first vent pipe to ensure the safety of the pressurization process. The first solenoid valve and the second solenoid valve are used to control the filling and releasing of gas in the high-pressure gas buffer tank.

[0008] Furthermore, the high-pressure storage tank and downstream pipeline system consists of a second one-way valve, a high-pressure hose, a four-way connector, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, a nitrogen purging cylinder, a fourth high-pressure needle valve, a second vacuum pump, a pressure-transformer pressure sensor, a third vent pipe, a high-pressure storage tank, a pipeline clamp, an external extension pipeline, a nozzle, a rupture disc, a pressure ring, a downstream pipeline, a piezoelectric pressure sensor, and a photoelectric sensor. The gas supply pipeline is connected to the four-way connector via a high-pressure hose, and then to the high-pressure storage tank. The end of the high-pressure storage tank is connected to the jet fire test pipeline and the fifth solenoid valve, and is fixed by the pipeline clamp. Once the test pressure is reached, the fifth solenoid valve opens to inject gas. The high-pressure storage tank can also be connected to a rupture disc with a specific design pressure, secured with gaskets / pressure rings. The high-pressure storage tank and downstream pipeline are connected via a pipe clamp. When the test gas pressure in the high-pressure storage tank reaches the rupture pressure of the rupture disc, the rupture disc ruptures, and the test gas is injected into the air through the downstream pipeline. If the rupture disc does not rupture, the gas in the pipeline can be vented by opening the fourth solenoid valve to ensure safety. The ignition control system consists of an igniter and an ignition controller, and can use different ignition methods to ignite the injected flame.

[0009] Furthermore, the data acquisition system mainly consists of a pressure transformer, a piezoelectric pressure sensor, a photoelectric sensor, thermocouples, a heat flow meter, and a data acquisition instrument. The pressure transformer is used to detect pressure changes within the high-pressure storage tank and measure the discharge pressure of the jet flame and the rupture pressure of the rupture disc. The piezoelectric pressure sensor and the photoelectric sensor are respectively installed on the upper and lower sides of the downstream pipeline. The piezoelectric pressure sensor is used to record pressure changes within the pipeline and monitor the formation and development of shock waves, while the photoelectric sensor is used to monitor the occurrence and development of spontaneous combustion flames within the pipeline. Thermocouples are arranged at equal intervals along the nozzle axis to detect the flame axis temperature and heat flow. The sensors are arranged along the flame axis to monitor the flame radiation of the ejected flame. The physical signals measured by the pressure transducer, piezoelectric pressure sensor, photoelectric sensor, thermocouple, and heat flow meter are all recorded by the data acquisition instrument. When the measured value of the pressure transducer reaches the specified test pressure value, the data acquisition instrument outputs a trigger signal, the fifth solenoid valve automatically opens, and the first high-speed camera starts working. During the spontaneous combustion test, when the measured value of the pressure transducer drops suddenly or the measured value of the piezoelectric pressure sensor closest to the rupture disc rises suddenly, the data acquisition instrument outputs a trigger signal, and the first and second high-speed cameras start working.

[0010] Furthermore, the dynamic image recording system consists of a first high-definition camera, a second high-definition camera, a first high-speed camera, a second high-speed camera, and a black screen wall. The black screen wall serves as the shooting background, facilitating post-processing of images. The first high-definition camera is used to capture the width of the jet flame, the second high-definition camera is used to capture the length of the jet flame and the flame propagation process, the first high-speed camera is used to capture the formation of Mach rings at the nozzle and the flame propagation process, and the second high-speed camera is used to capture the occurrence and development of spontaneous combustion flames in the downstream pipeline.

[0011] Furthermore, the flame behavior characteristic measurement system consists of thermocouples and heat flow meters. The thermocouples are arranged at equal intervals along the nozzle axis to detect the flame axis temperature, while the heat flow meters are regularly arranged along the flame axis to monitor the flame radiation of the ejected flame.

[0012] Furthermore, the solenoid valve control system mainly consists of a solenoid valve control cabinet, which contains five solenoid valve switches S1-S5, which control the opening and closing of the first, second, third, fourth, and fifth solenoid valves respectively. Due to the involvement of high pressure and flammable gas, the entire test device needs to have good airtightness, and the main body is sealed using the American Autoclave standard method.

[0013] This invention also includes a test method for a high-pressure flammable gas leak jet fire simulation test device, which includes the following steps for a spontaneous combustion ignition induced jet fire test:

[0014] Step 1: According to the test conditions, place the rupture disc with the specified design pressure at the outlet of the high-pressure storage tank, and connect and fix it to the downstream pipeline with a pressure ring and a pipe clamp. The piezoelectric pressure sensor and the photoelectric sensor are installed on the upper and lower sides of the downstream pipeline, respectively.

[0015] Step 2: Open the first nitrogen cylinder valve, adjust the fourth and fifth pressure reducing valves, start the air compressor, slightly open the gas booster, open the first and second solenoid valves, fill the high-pressure buffer tank with nitrogen to a certain pressure, close the fourth pressure reducing valve, and check the airtightness of the device.

[0016] Step 3: If the airtightness is good, open the fourth solenoid valve to purge the nitrogen in the device, close the first and fourth solenoid valves, open the third and fourth high-pressure needle valves and the first and second vacuum pumps to perform vacuuming, and close the second solenoid valve, the first and second vacuum pumps and the third and fourth high-pressure needle valves after the vacuuming is completed.

[0017] Step 4: Perform gas replacement in the gas booster. Open the second high-pressure needle valve to release the original gas in the gas booster. Open the first pressure reducing valve and start the gas booster at the same time. Purge the gas booster with 0.2MPa hydrogen to empty the nitrogen in the gas booster. Then close the second high-pressure needle valve and the first and fifth pressure reducing valves. Finally, turn off the gas booster.

[0018] Step 5: Open the first, second, and third pressure reducing valves and the corresponding combustible gas cylinder valves, adjust them to approximately the same release pressure and above 3MPa, and combine the gas from the three cylinders through the manifold. Control the input pressure of the combustible gas booster by adjusting the fifth pressure reducing valve, turn on the air compressor, drive the gas booster to start working, adjust the adjustment knob on the gas booster, open the first solenoid valve, and output combustible gas at the specified pressure to the high-pressure gas buffer tank. After the pressurization is completed, the gas booster will automatically stop working. At this time, close the first, second, and third pressure reducing valves and the first solenoid valve. The high-pressure gas filling is complete (up to 70MPa).

[0019] Step 6: Turn on the first and second high-speed cameras, the first and second high-definition cameras, and the data acquisition device;

[0020] Step 7: Open the second solenoid valve. The high-pressure gas buffer tank continuously supplies combustible gas into the high-pressure storage tank. When the pressure in the high-pressure storage tank reaches a certain level, the rupture disc breaks. After the piezoelectric pressure sensor in the pipeline detects the pressure change signal, it triggers the data acquisition instrument to start data acquisition. At the same time, the first high-speed camera and the second high-speed camera are activated to record the propagation of spontaneous combustion flame in the downstream pipeline and the behavior characteristics and dynamic parameters of the external jet flame. If no spontaneous combustion flame or jet flame is observed, immediately close the second solenoid valve to stop the supply of combustible gas.

[0021] Step 8: After the test measurement is completed, open the third solenoid valve and purge the test pipeline with nitrogen gas.

[0022] Furthermore, for the artificial ignition-induced jet fire test, the downstream pipeline is replaced with a jet fire test pipeline, and the jet fire ignition test is carried out through the fifth solenoid valve and different types of igniters (electric spark, high-temperature hot surface, lingering flame, etc.). The remaining operation steps are similar to the self-ignition-induced jet fire test process.

[0023] The beneficial effects of this invention are as follows:

[0024] This invention can conduct high-pressure combustible gas jet fire simulation tests under different working conditions, such as a wide range of relief pressure (0-70MPa) and different ignition methods (spontaneous combustion, propellant flame, high-temperature hot surface, etc.). It can also record the actual rupture pressure of the rupture disc, the intensity and changes of the shock wave after high-pressure gas leakage, the formation and development process of spontaneous combustion flame, the transformation of spontaneous combustion flame into jet flame, the geometric structure of jet flame under different ignition methods, the propagation process and thermal radiation, and the jet flame push-up and blow-out conditions. Furthermore, it allows for easy modification of test conditions, such as different combustible gases, different relief pressures, different downstream pipeline structures, and different burner nozzle sizes and shapes. Data recorded by pressure-transformer pressure sensors can monitor pressure changes, actual release pressure, and actual rupture pressure of rupture discs within high-pressure storage tanks. Data recorded by piezoelectric pressure sensors can monitor the formation and development of shock waves in downstream pipelines under certain release pressures, as well as the relationship between pressure changes in downstream pipelines over time. Photodiodes can monitor the spontaneous combustion of combustible gases in downstream pipelines, determining the propagation speed, location of spontaneous combustion, and ignition delay time. Dynamic image recording systems can capture the formation and development of flames in downstream pipelines, the transformation of spontaneous combustion flames into jet flames, the push-up and extinguishing of jet flames, the geometric structure of jet flames, and the propagation and development of flames. Downstream pipelines and external extension pipelines can be dismantled and replaced according to actual experimental needs. A viewing window can be created in the rectangular cross-section of the downstream pipeline to record the formation and development of spontaneous combustion flames. The ignition system can be changed to different ignition methods, which is beneficial for analyzing the differences in jet flame behavior characteristics under different ignition methods. This invention can be used to study high-pressure combustible gas leakage jet fire under different operating conditions, such as: ① It can realize the study of different ignition methods. By changing the self-ignition pipe and the jet fire pipe, as well as changing the ignition method of the ignition system, the differences in jet fire behavior characteristics under different ignition methods can be studied; ② It can realize wide pressure range research. By adjusting the output pressure of the booster, it can realize the study of different combustible gas leakage jet fire under 0-70MPa relief pressure; ③ It can carry out multi-characteristic parameter coupling research. The experiment can measure many parameters such as relief pressure, shock wave overpressure, axial flame temperature, flame thermal radiation, flame length and width, nozzle size and shape, etc., which facilitates the conduct of multi-characteristic parameter coupling research.

[0025] This invention can be used to study the influence of different combustible gas types, leakage pressure (up to 70 MPa), ignition methods (spontaneous combustion, artificial ignition), nozzle structure size, external environment and other factors on the behavior characteristics and dynamic parameters of high-pressure jet flames, including ignition mechanism, flame suspension and extinguishing instability, flame shape (length, width and tilt angle, etc.) and flame microstructure and its dynamics, temperature, flame thermal radiation, etc., to obtain the critical conditions for the formation of stable jet flames. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the ignition jet fire test device of the present invention;

[0027] Figure 2 This is a schematic diagram of the overall structure of the self-ignition jet fire test device of the present invention;

[0028] In the diagram, 1-High-pressure test gas cylinder group; 2-First nitrogen cylinder; 3-First pressure reducing valve; 4-Second pressure reducing valve; 5-Third pressure reducing valve; 6-Fourth pressure reducing valve; 7-Manifold; 8-Fifth pressure reducing valve; 9-First high-pressure needle valve; 10-First check valve; 11-Air compressor; 12-Gas booster; 13-Safety relief valve; 14-First vent pipe; 15-Second high-pressure needle valve; 16-Second vent pipe; 17-First solenoid valve; 18-Third high-pressure needle valve; 19-First vacuum pump; 20-Pressure gauge; 21-High-pressure gas buffer tank; 22-Second solenoid valve; 23-Second check valve; 24-High-pressure hose; 25-Four-way connector; 26-Third solenoid valve; 27-Second nitrogen cylinder; 28-Fourth high-pressure needle valve; 29-Second vacuum pump; 30-Pressure transformer pressure sensor; 31-Fourth solenoid valve; 32-Third vent pipe; 33-High pressure Storage tank; 34-Pipe clamp; 35-Fifth solenoid valve; 36-External expansion pipe; 37-Nozzle; 38-Rupture disc; 39-Gasket / Pressure ring; 40-Downstream pipe; 41-Piezoelectric pressure sensor; 42-Photoelectric sensor; 43-Igniter; 44-Ignition controller; 45-Thermocouple; 46-Heat flow meter; 47-Black curtain wall; 48-First high-definition camera; 49-Second high-definition camera; 50-First high-speed camera; 51-Second high-speed camera; 52-Data acquisition instrument; 53-Solenoid valve control cabinet; S1-First solenoid valve control switch; S2-Second solenoid valve control switch; S3-Third solenoid valve control switch; S4-Fourth solenoid valve control switch; S5-Fifth solenoid valve control switch; 12-1-Low-pressure gas inlet; 12-2-Driving gas inlet; 12-3-High-pressure gas outlet; 12-4-Safety vent. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0030] The embodiments of the present invention are described below with reference to the accompanying drawings.

[0031] like Figure 1 and Figure 2As shown, the present invention is a high-pressure combustible gas leak jet fire simulation test device, which includes: a gas supply system, a gas pressurization and buffering system, a high-pressure storage tank and downstream pipeline system, an ignition control system, a data acquisition system, a dynamic image recording system, and a solenoid valve control system.

[0032] The gas supply system mainly consists of a high-pressure test gas cylinder group 1, a first nitrogen cylinder 2, a first pressure reducing valve 3, a second pressure reducing valve 4, a third pressure reducing valve 5, a fourth pressure reducing valve 6, a fifth pressure reducing valve 8, a manifold 7, a first high-pressure needle valve 9, and a first one-way valve 10. The first pressure reducing valve 3, the second pressure reducing valve 4, the third pressure reducing valve 5, and the fourth pressure reducing valve 6 are directly connected to their respective gas cylinders, allowing for pressure adjustment of the cylinders. They are also connected to the manifold 7 via high-pressure rubber hoses. The high-pressure rubber hoses have an outer diameter of 19mm, an inner diameter of 8mm, and a length of 1m. The manifold 7, made of pure copper, is 2m long and collects the gas from the high-pressure test gas cylinder group, primarily used in the high-pressure testing section to ensure a sufficient gas supply.

[0033] The gas pressurization and buffering system consists of an air compressor 11, a gas booster 12, a safety relief valve 13, a first vent pipe 14, a second vent pipe 16, a second high-pressure needle valve 15, a third high-pressure needle valve 18, a first solenoid valve 17, a second solenoid valve 22, a first vacuum pump 19, a pressure gauge 20, and a high-pressure gas buffer tank 21. The air compressor 11 can rotate at 2880 r / min and can provide a driving pressure of 0.8 MPa, providing driving force for the gas booster 12. The gas booster 12 has dimensions of 1 m long, 0.75 m wide, and 1.2 m high, a pressure ratio of 60:1, a maximum output pressure of 140 MPa, an input pressure of 3 MPa, and a gas flow rate of approximately 140 nl / min at a driving pressure of 0.62 MPa. The safety relief valve 13 is available in three specifications: 20-30 MPa, 35-40 MPa, and 20-17 MPa. 0MPa is used to ensure safety under different test conditions; the first vent pipe 14 has an outer diameter of 16mm and an inner diameter of 6mm, and is used to release combustible gas to a safe area after the safety relief valve 13 is opened; the second high-pressure needle valve 15 is used to vent gas in the booster, and the third high-pressure needle valve 18 is used to block the first vacuum pump 19, both with a pressure resistance of 100MPa; the first solenoid valve 17 and the second solenoid valve 22 are both explosion-proof and can withstand pressures of over 100MPa; the first vacuum pump 19 is used for vacuum extraction in the pipeline, with an ultimate vacuum of 1×10 -6 Pressure gauge 20 is used to monitor the pressure changes of high-pressure gas buffer tank 21. The pressure gauge is explosion-proof and has a measurement range of 0-80MPa. High-pressure gas buffer tank 21 has a volume of 23L, a pressure resistance of over 100MPa, and a working pressure of 70MPa.

[0034] The air compressor 11 drives the gas booster 12 through the drive gas inlet 12-2. The gas supplied by the gas supply system enters the booster 12 through the low-pressure gas inlet 12-1 and is pressurized. After pressurization, the gas enters the high-pressure gas buffer tank 21 through the high-pressure gas outlet 12-3 for temporary storage. The safety vent 12-4 is connected to the safety vent valve 13 and the first vent pipe 14 to ensure the safety of the pressurization process.

[0035] The high-pressure storage tank and downstream pipeline system consist of a second one-way valve 23, a high-pressure hose 24, a four-way connector 25, a third solenoid valve 26, a fourth solenoid valve 31, a fifth solenoid valve 35, a second nitrogen cylinder 27, a fourth high-pressure needle valve 28, a second vacuum pump 29, a pressure-transformer pressure sensor 30, a third vent pipe 32, a high-pressure storage tank 33, a pipe clamp 34, an external extension pipe 36, a nozzle 37, a rupture disc 38, a gasket / pressure ring 39, a downstream pipeline 40, a piezoelectric pressure sensor 41, and a photoelectric sensor 42. The second one-way valve 23 is pressure-resistant to 100MPa; the high-pressure hose 24 is pressure-resistant to 100MPa or higher; the third solenoid valve 26 is pressure-resistant to 100MPa and is used to control the nitrogen purging of the second nitrogen cylinder 27; the fourth high-pressure needle valve 28 is used to control the second vacuum pump 29 for vacuum extraction and is pressure-resistant to 100MPa; the pressure-transformer pressure sensor 30 has a measurement range of 0-70MPa and a response frequency ≥500kHz and is used to monitor the pressure changes in the high-pressure storage tank 33; the fourth solenoid valve 31 is pressure-resistant to 100MPa and is used to control the gas venting of the test device; the high-pressure storage tank 33 is a cylindrical cavity structure made of 316L stainless steel with a volume of 0.071L, and is filled with test gas to a certain pressure; the rupture disc 38 is connected to the high-pressure storage tank 33 through a gasket / pressure ring 39 and a pipe clamp 34. The downstream pipeline 40 is securely sealed. When the pressure inside the high-pressure storage tank 33 exceeds the rupture pressure of the rupture disc 38, the rupture disc 38 ruptures, and the test gas can be ejected into the air through the downstream pipeline 40, the external expansion pipeline 36, and the nozzle 37. The high-pressure storage tank 33 can also be directly connected to the jet fire pipeline, and the release of combustible gas can be controlled by the fifth solenoid valve 35. The gasket / pressure ring 39 and the pipeline clamp 34 are both made of 316 stainless steel. The size, shape, design pressure of the rupture disc, and the shape of the gasket / pressure ring opening can all be changed. The downstream pipeline 40 is made of 316 stainless steel, and its cross-sectional structure, length, and inner diameter can all be changed. The external expansion pipeline 36 is directly connected to the end of the downstream pipeline 40, and its length and inner diameter can all be changed. The inner diameter and outlet shape of the nozzle 37 can all be changed.

[0036] The ignition control system consists of an igniter 43 and an ignition controller 44. The type of igniter can be changed according to the experimental needs, such as a dwelling flame, an electric spark, or a high-temperature hot surface, to compare with spontaneous combustion jet fire and realize the research on jet fire with different ignition methods.

[0037] The data acquisition system mainly consists of a pressure transformer pressure sensor 30, a piezoelectric pressure sensor 41, a photoelectric sensor 42, thermocouples 45, a heat flow meter 46, and a data acquisition instrument 52. The pressure transformer pressure sensor 30 is used to detect pressure changes within the high-pressure storage tank 33, measure the actual rupture pressure of the rupture disc 38 and the actual release pressure of the jet flame, with a measurement range of 0-70 MPa and a response frequency ≥500 kHz. The piezoelectric pressure sensor 41 and the photoelectric sensor 42 are respectively installed on the upper and lower sides of the downstream pipeline 40. The piezoelectric pressure sensor 41 has a measurement range of 0-70 MPa and a response frequency ≥500 kHz, used to record pressure changes within the pipeline and monitor the formation and development of shock waves. The photoelectric sensor 42 has a measurement spectrum range of 200-1100 nm, used to monitor the occurrence and development of spontaneous combustion flames within the pipeline. Thermocouples 45 are evenly spaced along the axis of the nozzle 37, capable of measuring temperatures from 0-1800℃, used to detect the flame axis temperature. The heat flow meter 46 is regularly arranged beside the flame axis, with a range of 0-50 kW / m. 2 It is used to monitor the flame radiation of the jet flame; the physical signals measured by the pressure transducer 30, the piezoelectric pressure sensor 41, the photoelectric sensor 42, the thermocouple 45 and the heat flow meter 46 are all recorded by the data acquisition instrument 52; the layout and installation method of various measuring elements change with the change of test conditions.

[0038] The dynamic image recording system consists of a first high-definition camera 48, a second high-definition camera 49, a first high-speed camera 50, a second high-speed camera 51, and a black screen wall 47. The first high-definition camera 48 and the second high-definition camera 49 have a shooting speed of 1000fps; the first high-speed camera 50 and the second high-speed camera 51 have a shooting speed of 3,000-25,000fps and a resolution of 1920×1080. When the measured value of the pressure sensor 30 drops suddenly or the measured value of the piezoelectric pressure sensor 41 closest to the rupture disc 38 rises suddenly, the data acquisition unit 52 outputs a trigger signal, and the first high-speed camera 50 and the second high-speed camera 51 start working.

[0039] The solenoid valve control system mainly consists of a solenoid valve control cabinet 53, which contains five solenoid valve switches S1-S5, which control the opening and closing of the first solenoid valve 17, the second solenoid valve 22, the third solenoid valve 26, the fourth solenoid valve 31, and the fifth solenoid valve 35, respectively. All five solenoid valves are explosion-proof and can withstand a pressure of 100MPa, enabling remote and safe operation of the solenoid valves and achieving semi-automatic control of high-pressure storage tank filling, safe pressure relief, and high-pressure buffer tank filling.

[0040] The main pipelines of the device are all sealed using the American Autoclave standard method, which provides a more complete sealing performance. The main pipelines are all made of 316L stainless steel and can withstand pressure up to 100MPa.

[0041] The present invention also provides a test method for a high-pressure flammable gas leak jet fire simulation test device, which includes the following steps:

[0042] (i) Spontaneous ignition-induced jet fire test, such as Figure 2 As shown:

[0043] Step 1: According to the test conditions, place the rupture disc 38 with the specified design pressure at the outlet of the high-pressure storage tank 33, and connect and fix it to the downstream pipeline 40 with the gasket / pressure ring 39 and the pipe clamp 34. The piezoelectric pressure sensor 41 and the photoelectric sensor 42 are respectively installed on the upper and lower sides of the downstream pipeline 40.

[0044] Step 2: Open the valve of the first nitrogen cylinder 2, adjust the fourth pressure reducing valve 6 and the fifth pressure reducing valve 8, start the air compressor 11, slightly open the gas booster 12, open the first solenoid valve 17 and the second solenoid valve 22, fill the high-pressure gas buffer tank 21 with nitrogen to a certain pressure, close the fourth pressure reducing valve 6, and check the airtightness of the device.

[0045] Step 3: If the airtightness is good, open the fourth solenoid valve 31 to purge the nitrogen in the device, close the first solenoid valve 17 and the fourth solenoid valve 31, open the third high-pressure needle valve 18, the fourth high-pressure needle valve 28 and the first vacuum pump 19 and the second vacuum pump 29 to perform vacuuming, and close the second solenoid valve 22, the first vacuum pump 19, the second vacuum pump 22 and the third high-pressure needle valve 18 and the fourth high-pressure needle valve 28 after the vacuuming is completed.

[0046] Step 4: Perform gas replacement in the gas booster 12. Open the second high-pressure needle valve 15 to release the original gas in the gas booster 12. Open the first pressure reducing valve 3 and start the gas booster 12 at the same time. Purge the gas booster 12 with 0.2MPa hydrogen gas to empty the nitrogen gas in the gas booster 12. Then close the second high-pressure needle valve 15, the first pressure reducing valve 3, and the fifth pressure reducing valve 8. Finally, turn off the gas booster 12.

[0047] Step 5: Open the first pressure reducing valve 3, the second pressure reducing valve 4, the third pressure reducing valve 5 and the corresponding combustible gas cylinder valve, adjust them to approximately the same release pressure and higher than 3MPa, and combine the gas in the three gas cylinders through the manifold 7. Control the input pressure of the combustible gas booster 12 by adjusting the fifth pressure reducing valve 8, turn on the air compressor 11, drive the combustible gas booster 12 to start working, adjust the adjustment knob on the combustible gas booster 12, open the first solenoid valve 17, and output combustible gas at the specified pressure to the high-pressure gas buffer tank 21. After the pressurization is completed, the combustible gas booster 12 will automatically stop working. At this time, close the first pressure reducing valve 3, the second pressure reducing valve 4, the third pressure reducing valve 5 and the first solenoid valve 17. The high-pressure gas filling is completed (up to 70MPa).

[0048] Step 6: Turn on the first high-definition camera 48, the second high-definition camera 49, the first high-speed camera 50, the second high-speed camera 51, and the data acquisition device 52;

[0049] Step 7: Open the second solenoid valve 22. The high-pressure gas buffer tank 21 continuously supplies combustible gas to the high-pressure storage tank 33. When the pressure in the high-pressure storage tank 33 reaches a certain level, the rupture disc 38 ruptures. After the piezoelectric pressure sensor 41 in the pipeline detects the pressure change signal, it triggers the data acquisition instrument 52 to start data acquisition. At the same time, the first high-speed camera 50 and the second high-speed camera 51 are activated to capture and record the propagation of spontaneous combustion flame in the downstream pipeline 40 and the behavior characteristics and dynamic parameters of the external jet flame. If no spontaneous combustion flame or jet flame is observed, immediately close the second solenoid valve 22 to stop the supply of combustible gas.

[0050] Step 8: After the test measurement is completed, open the third solenoid valve 26 and purge the test pipeline with nitrogen gas.

[0051] (ii) Artificial ignition-induced jet fire test

[0052] like Figure 1 As shown, the downstream pipe 40 is replaced with a jet fire test pipe, and the jet fire ignition test is carried out through the fifth solenoid valve 35 and different types of igniters (electric spark, high temperature hot surface, lingering flame, etc.). The remaining operation steps are similar to the self-ignition induced jet fire test process.

[0053] Figure 1 and Figure 2 The main difference lies in the downstream pipeline, specifically the section after high-pressure storage tank 33. Figure 1 The image shows a high-pressure hydrogen leak ignition test apparatus. Figure 2 It is a high-pressure hydrogen leakage spontaneous combustion test device.

[0054] The parts of this invention not disclosed in detail are well-known technologies in the field.

[0055] Although the illustrative specific embodiments of the present invention have been described above to enable those skilled in the art to understand the invention, it should be understood that the invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the invention as defined and determined by the appended claims, and all inventions utilizing the concept of the present invention are protected.

Claims

1. A high-pressure combustible gas leak jet fire simulation test device, characterized in that, The system includes a gas supply system, a gas pressurization and buffering system, a high-pressure storage tank and downstream pipeline system, an ignition control system, a data acquisition system, a dynamic image recording system, a flame characteristic parameter measurement system, and a solenoid valve control system. The gas supply system provides a continuous and stable gas source for the gas pressurization and buffering system, and also provides a gas source for pre-test airtightness testing and post-test device purging. The gas pressurization and buffering system includes a gas compressor and a high-pressure gas buffer tank for pressurizing and storing medium and low-pressure gases, and providing a continuous wide-pressure range of gas (1-70 MPa) to the high-pressure storage tank as needed. The high-pressure storage tank and downstream pipeline system includes a high-pressure storage tank and downstream pipelines. When the ignition method is auto-ignition, the downstream pipeline includes rupture discs and gaskets / pressure... The system comprises a ring, a pipe clamp, and a metal pipe; when ignited manually, the downstream pipe includes a fifth solenoid valve, a pipe clamp, a metal pipe, and an external extension pipe; the ignition control system includes an igniter and an ignition controller to provide different ignition methods; the data acquisition system records pressure changes in the high-pressure storage tank, pressure changes in the downstream pipe, light signal changes, and temperature and heat flux parameter changes, and inputs trigger signals to the dynamic image recording system; the dynamic image recording system records the propagation of spontaneous combustion flame in the downstream pipe, the gas jet at the pipe opening, and the dynamic development process of the jet flame; the flame characteristic parameter measurement system measures the temperature changes along the jet flame axis and around it, and the changes in flame thermal radiation; the opening and closing of the solenoid valve is controlled by the solenoid valve control system. The gas supply system includes a high-pressure test gas cylinder group (1), a first nitrogen cylinder (2), a first pressure reducing valve (3), a second pressure reducing valve (4), a third pressure reducing valve (5), a fourth pressure reducing valve (6), a fifth pressure reducing valve (8), a manifold (7), a first high-pressure needle valve (9), and a first check valve (10). The high-pressure test gas cylinder group (1) can be used individually or in combination according to the pressure inside the gas cylinder and the test pressure requirements. The high-pressure test gas cylinder group is connected to the manifold (7) through the first pressure reducing valve (3), the second pressure reducing valve (4), and the third pressure reducing valve (5). Similarly, the first nitrogen cylinder (2) is connected to the manifold (7) through the fourth pressure reducing valve (6). The fifth pressure reducing valve (8) is used to display the gas pressure in the pipeline and control the gas supply pressure to the test pipeline. When the gas cylinder is replaced, the pipeline is emptied. At this time, the first high-pressure needle valve (9) is opened and the fifth pressure reducing valve (8) is closed to perform the emptying process. The first check valve (10) is used to ensure one-way passage of gas. The gas pressurization and buffering system includes an air compressor (11), a gas booster (12), a safety relief valve (13), a first vent pipe (14), a second vent pipe (16), a second high-pressure needle valve (15), a third high-pressure needle valve (18), a first solenoid valve (17), a second solenoid valve (22), a first vacuum pump (19), a pressure gauge (20), and a high-pressure gas buffer tank (21). The air compressor (11) pressurizes the gas through the drive gas inlet (12-2) of the gas booster (12). The compressor (12) provides the drive. The gas supplied by the gas supply system enters the compressor through the low-pressure gas inlet (12-1) of the gas booster (12) for pressurization. After pressurization, the gas enters the high-pressure gas buffer tank (21) through the high-pressure gas outlet (12-3) for temporary storage. The safety vent (12-4) is connected to the safety vent valve (13) and the first vent pipe (14) to ensure the safety of the pressurization process. The first solenoid valve (17) and the second solenoid valve (22) are used to control the filling and releasing of gas in the high-pressure gas buffer tank.

2. The high-pressure combustible gas leak jet fire simulation test device according to claim 1, characterized in that, The high-pressure storage tank and downstream pipeline system include a second one-way valve (23), a high-pressure hose (24), a four-way connector (25), a third solenoid valve (26), a fourth solenoid valve (31), a fifth solenoid valve (35), a second nitrogen cylinder (27), a fourth high-pressure needle valve (28), a second vacuum pump (29), a pressure-transformer pressure sensor (30), a third vent pipe (32), a high-pressure storage tank (33), a pipe clamp (34), an external extension pipe (36), a nozzle (37), a rupture disc (38), a gasket / pressure ring (39), a downstream pipeline (40), a piezoelectric pressure sensor (41), and a photoelectric sensor (42). The gas supply pipeline is connected to the four-way connector (25) via the high-pressure hose (24), and then connected to the high-pressure storage tank (33). The end of the high-pressure storage tank (33) is connected to the jet fire test pipeline and... The fifth solenoid valve (35) is connected and fixed by the pipe clamp (34). After the test pressure is reached, the fifth solenoid valve (35) opens to spray gas; or the high-pressure storage tank (33) is connected to the rupture disc (38) and secured with a gasket / pressure ring (39). The high-pressure storage tank (33) and the downstream pipe (40) are connected by the pipe clamp (34). When the test gas pressure in the high-pressure storage tank (33) reaches the rupture pressure of the rupture disc (38), the rupture disc (38) ruptures and the test gas is sprayed into the air through the downstream pipe (40). If the rupture disc does not rupture, the gas in the pipe is emptied by opening the fourth solenoid valve (31) to ensure safety. The ignition control system consists of an igniter (43) and an ignition controller (44), which are used to ignite the spray flame using different ignition methods.

3. The high-pressure combustible gas leak jet fire simulation test device according to claim 1, characterized in that, The dynamic image recording system consists of a first high-definition camera (48), a second high-definition camera (49), a first high-speed camera (50), a second high-speed camera (51), and a black screen wall (47). The black screen wall (47) serves as the shooting background, which facilitates post-processing of images. The first high-definition camera (48) is used to shoot the width of the jet flame, the second high-definition camera (49) is used to shoot the length of the jet flame and the flame propagation process, the first high-speed camera (50) is used to shoot the formation of Mach rings at the nozzle (37) and the flame propagation process, and the second high-speed camera (51) is used to shoot the occurrence and development of spontaneous combustion flames in the downstream pipeline.

4. The high-pressure flammable gas leak jet fire simulation test device according to claim 2, characterized in that, The flame behavior characteristic measurement system consists of thermocouples (45) and heat flow meters (46). The thermocouples (45) are arranged at equal intervals along the axis of the nozzle (37) to detect the temperature of the flame axis. The heat flow meters (46) are arranged regularly along the flame axis to monitor the flame radiation of the jet flame.

5. The high-pressure combustible gas leak jet fire simulation test device according to claim 1, characterized in that, The solenoid valve control system includes a solenoid valve control cabinet (53), which is equipped with five solenoid valve switches to control the opening and closing of the first solenoid valve (17), the second solenoid valve (22), the third solenoid valve (26), the fourth solenoid valve (31), and the fifth solenoid valve (35), respectively.

6. The high-pressure combustible gas leak jet fire simulation test device according to claim 1, characterized in that, The data acquisition system includes a pressure transducer (30), a piezoelectric pressure sensor (41), a photoelectric sensor (42), a thermocouple (45), a heat flow meter (46), and a data acquisition instrument (52). The pressure transducer (30) is used to detect pressure changes in the high-pressure storage tank (33) and measure the discharge pressure of the jet fire and the rupture pressure of the rupture disc (38). The piezoelectric pressure sensor (41) and the photoelectric sensor (42) are installed on the upper and lower sides of the downstream pipeline (40), respectively. The piezoelectric pressure sensor (41) is used to record pressure changes in the pipeline and monitor the formation and development of shock waves. The photoelectric sensor (42) is used to monitor the occurrence and development of spontaneous combustion flames in the pipeline. Thermocouples (45) are arranged at equal intervals along the axis of the nozzle (37) to detect the flame axis temperature. The heat flow meter (46) is arranged regularly. The flames are positioned along the flame axis to monitor the flame radiation of the jet flame. The physical signals measured by the pressure transducer (30), piezoelectric pressure sensor (41), photoelectric sensor (42), thermocouple (45), and heat flow meter (46) are recorded by the data acquisition instrument (52). When the measured value of the pressure transducer (30) reaches the test specified pressure value, the data acquisition instrument (52) outputs a trigger signal, the fifth solenoid valve (35) automatically opens, and the first high-speed camera (50) starts working. When conducting the self-ignition test, when the measured value of the pressure transducer (30) drops sharply or the measured value of the piezoelectric pressure sensor (41) closest to the rupture disc (38) rises sharply, the data acquisition instrument (52) outputs a trigger signal, and the first high-speed camera (50) and the second high-speed camera (51) start working.

7. The test method for a high-pressure flammable gas leak jet fire simulation test device according to any one of claims 1-6, characterized in that, The self-ignition induced jet fire test includes the following steps: Step 1: According to the test conditions, place the rupture disc (38) with the specified design pressure at the outlet of the high-pressure storage tank (33), and connect and fix it to the downstream pipeline (40) with the gasket / pressure ring (39) and the pipe clamp (34). The piezoelectric pressure sensor (41) and the photoelectric sensor (42) are respectively installed on the upper and lower sides of the downstream pipeline (40). Step 2: Open the first nitrogen cylinder valve, adjust the fourth pressure reducing valve (6) and the fifth pressure reducing valve (8), start the air compressor (11), slightly open the gas booster (12), open the first solenoid valve (17) and the second solenoid valve (22), fill the high-pressure gas buffer tank (21) with nitrogen to a certain pressure, close the fourth pressure reducing valve (6), and check the airtightness of the device; Step 3: If the airtightness is good, open the fourth solenoid valve (31) to remove nitrogen from the device, close the first solenoid valve (17) and the fourth solenoid valve (31), open the third high-pressure needle valve (18), the fourth high-pressure needle valve (28), the first vacuum pump (19), and the second vacuum pump (29) to perform vacuuming. After vacuuming is completed, close the second solenoid valve (22), the first vacuum pump (19), the second vacuum pump (29), the third high-pressure needle valve (18), and the fourth high-pressure needle valve (28). Step 4: Perform gas replacement in the gas booster (12), open the second high-pressure needle valve (15) to release the original gas in the gas booster (12), open the first pressure reducing valve (3), and start the gas booster (12) at the same time. Use 0.2MPa hydrogen to purge the nitrogen in the gas booster (12), then close the second high-pressure needle valve (15), the first pressure reducing valve (3), and the fifth pressure reducing valve (8), and finally close the gas booster (12). Step 5: Open the first pressure reducing valve (3), the second pressure reducing valve (4), the third pressure reducing valve (5) and the corresponding combustible gas cylinder valve, adjust them to the same release pressure and higher than 3MPa, and merge the gas in the three gas cylinders through the manifold (7). Control the input pressure of the input gas booster (12) by adjusting the fifth pressure reducing valve (8), turn on the air compressor (11), drive the gas booster (12) to start working, adjust the adjustment knob on the gas booster (12), open the first solenoid valve (17), and output combustible gas at the specified pressure to the high-pressure gas buffer tank (21). After the pressurization is completed, the gas booster (12) will automatically stop working. At this time, close the first pressure reducing valve (3), the second pressure reducing valve (4), the third pressure reducing valve (5) and the first solenoid valve (17). The high-pressure gas filling is completed. Step 6: Turn on the first high-definition camera (48), the second high-definition camera (49), the first high-speed camera (50), the second high-speed camera (51), and the data acquisition device (52); Step 7: Open the second solenoid valve (22). The high-pressure gas buffer tank (21) continuously supplies combustible gas into the high-pressure storage tank (33). When the pressure in the high-pressure storage tank (33) reaches a certain level, the rupture disc (38) ruptures. After the piezoelectric pressure sensor (41) in the pipeline detects the pressure change signal, it triggers the data acquisition instrument (52) to start data acquisition. At the same time, the first high-speed camera (50) and the second high-speed camera (51) are activated to take pictures and record the propagation of spontaneous combustion flame in the downstream pipeline (40) and the behavior characteristics and dynamic parameters of external jet flame. If no spontaneous combustion flame or jet flame is observed, the second solenoid valve (22) is immediately closed to stop the supply of combustible gas. Step 8: After the test measurement is completed, open the third solenoid valve (26) and purge the test pipeline with nitrogen gas.

8. The test method according to claim 7, characterized in that, For artificial ignition-induced jet fire tests, the downstream pipeline is replaced with a jet fire test pipeline, and the jet fire ignition test operation is carried out through the fifth solenoid valve and different types of igniters; the different types of igniters include electric spark, high-temperature hot surface or dwelling flame igniters.

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