Large-scale natural gas hydrogen-doped gas leakage and jet fire testing device and method

Abstract

The invention provides a large-scale natural gas hydrogen-doped gas leakage and jet fire testing device and method. A large-scale natural gas hydrogen-doped gas leakage and jet fire testing device comprises a hydrogen gas cylinder, a pressure sensor, a temperature sensor, a sheathed thermocouple, an electric ignition device, a leakage device, a natural gas tank car, a vacuum pump, a pipeline, an infrared camera, a computer, a data acquisition instrument, a gas concentration sensor and a thermal radiation sensor. The hydrogen cylinder, the pressure sensor, the temperature sensor, the leakage device, the natural gas tank car and the vacuum pump are all connected with the pipeline, and the sheathed thermocouple, the electric ignition device, the infrared camera, the gas concentration sensor and the thermal radiation sensor are all adjacent to the leakage device. The data acquisition instrument is respectively connected with the pressure sensor, the temperature sensor, the sheathed thermocouple, the gas concentration sensor and the thermal radiation sensor, and the infrared camera and the data acquisition instrument are both connected with the computer.

Description

Technical Field

[0001] The invention relates to the technical field of open space mixed gas leakage / jet fire experiments, and in particular to a large-scale natural gas hydrogen-mixed gas leakage and jet fire testing device and method. Background Art

[0002] In order to achieve the goal of energy conservation and emission reduction, the transportation method of natural gas mixed with hydrogen is becoming more and more widely used in the actual production process. At present, the research on gas leakage is mainly carried out on single gas and small-scale cases, while there are few studies on mixed gas leakage in actual pipeline transportation. Therefore, studying the diffusion characteristics of natural gas mixed with hydrogen with different mixing ratios under factors such as leakage pressure and leakage pore size has guiding significance for safe production.

[0003] In the actual production process, the leakage of combustible gas is affected by factors such as the leakage size, pipeline pressure and ambient wind speed. With the passage of time, the concentration of the leaked combustible gas may reach the explosion limit, and may cause an explosion accident when encountering factors such as high temperature and ignition source. Therefore, the leaked gas can be ignited by an electric ignition device, and the research on the characteristics of the combustible gas jet flame has important practical and theoretical guiding significance for safe production.

[0004] There are two main types of experimental devices and operation methods for leaking / jetting fire of natural gas-hydrogen mixed gas with different blending ratios in related technologies: (1) Conducting experiments on small-scale containers in closed spaces such as wind tunnel laboratories, and observing the diffusion characteristics of gas clouds by installing gas concentration sensors. (2) The combustible gas leaks at a uniform rate through a mass flow meter, and continuous electric ignition is performed outside the leak port to observe the jet fire phenomenon of different pressures and leak apertures.

[0005] Although the above experimental devices and their operation methods can realize the experimental study of leakage / jet fire of combustible gas under different pressures and leakage apertures, they have the following shortcomings: 1) The experiments on the escape and jet fire of combustible gas are mostly limited to small-scale containers, but the actual production process is transported through large-scale pipelines, and there are few experimental studies using large-scale pipelines. 2) Most of the research on the jet fire phenomenon of combustible gas is limited to the research under the condition of uniform leakage, and the research on jet fire from high-pressure leakage to normal pressure in the actual production process is relatively scarce. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device and method in view of the deficiencies in the prior art.

[0007] The technical solution of the present invention to solve the above technical problems is as follows: a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device, comprising: a hydrogen cylinder, a pressure sensor, a temperature sensor, an armored thermocouple, an electric ignition device, a leakage device, a natural gas tanker, a vacuum pump, a pipeline, an infrared camera, a computer, a data acquisition instrument, a gas concentration sensor, and a thermal radiation sensor. The hydrogen cylinder, the pressure sensor, the temperature sensor, the leakage device, the natural gas tanker, and the vacuum pump are all connected to the pipeline, the armored thermocouple, the electric ignition device, the infrared camera, the gas concentration sensor, and the thermal radiation sensor are all adjacent to the leakage device, the data acquisition instrument is respectively connected to the pressure sensor, the temperature sensor, the armored thermocouple, the gas concentration sensor, and the thermal radiation sensor, and the infrared camera and the data acquisition instrument are both connected to the computer.

[0008] The beneficial effects of the technical solution of the present invention are: the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing leakage devices of different sizes. The leakage / jet fire experiment is carried out on the leakage of the mixed gas by controlling the electric ignition device. The gas cloud leakage process is observed by an infrared camera or the shape and length of the jet fire are studied. The infrared camera is used to record the propagation process of gas leakage or jet flame when the pipeline leaks at high pressure. The armored thermocouple is used to study the temperature change of the gas cloud leaking from the pipeline, the gas concentration sensor is used to study the concentration distribution at different distances, and the concentration change of the escaped gas cloud is recorded. The thermal radiation sensor is used to study the thermal radiation at different distances and record the influence of flame radiation. The vacuum pump is used for vacuum treatment after the combustible gas leaks. The data acquisition instrument is used to collect data from the pressure sensor, temperature sensor inside the large-scale pipeline and the armored thermocouple, gas concentration sensor and thermal radiation sensor outside, and send the collected data to the computer.

[0009] Furthermore, the pressure sensor and the temperature sensor are both connected to the pipe via threads, and the number of the gas concentration sensor and the thermal radiation sensor are both multiple, and the multiple gas concentration sensors and the multiple thermal radiation sensors are respectively arranged in sequence along the adjacent leakage device toward the periphery.

[0010] The beneficial effects of adopting the above further technical solution are: using the gas concentration sensor to study the concentration distribution at different distances, and using the thermal radiation sensor to study the thermal radiation at different distances. The pipeline is connected to the pressure sensor through a thread to measure the pressure value when the gas is injected into the confined space. The pipeline is connected to the temperature sensor through a thread to measure the temperature value when the gas is injected into the confined space.

[0011] Furthermore, the hydrogen cylinder, the natural gas tanker and the vacuum pump are all connected to the pipeline via a gas injection valve.

[0012] The beneficial effect of adopting the above further technical solution is that the provision of the gas injection valve facilitates opening and closing of the corresponding pipeline according to actual needs.

[0013] Furthermore, the leakage device comprises: an extension tube and a solenoid valve, the solenoid valve is connected to the pipeline, and the extension tube is connected to the solenoid valve.

[0014] The beneficial effect of adopting the above further technical solution is that the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing electromagnetic valves of different sizes. In order to protect the electromagnetic valve from the high temperature of the flame, an extension tube of the corresponding size is installed.

[0015] Furthermore, the armored thermocouple and the electric ignition device are both installed on a bracket, and the bracket is adjacent to the leakage device; the bracket is a V-shaped or L-shaped structure, and there are multiple armored thermocouples, and the multiple armored thermocouples are arranged in sequence on the bracket along the adjacent leakage device toward the periphery.

[0016] The beneficial effects of adopting the above further technical solution are: using armored thermocouples to study the temperature change of the gas cloud directly above the pipeline, and using the bracket to control the ignition position, so as to obtain the combustion and explosion parameters of the jet flame at different ignition positions.

[0017] Furthermore, the electric ignition device includes: an electric ignition electrode and an electric ignition switch, and the electric ignition electrode is connected to the electric ignition switch.

[0018] The beneficial effect of adopting the above further technical solution is that the electric ignition device is used to control the electric ignition electrode to ignite. The leakage / jet fire test of the mixed gas is carried out by controlling the electric ignition device.

[0019] In addition, the present invention also provides a large-scale natural gas hydrogen-mixed gas leakage and jet fire test method, based on any one of the large-scale natural gas hydrogen-mixed gas leakage and jet fire test devices described above, the large-scale natural gas hydrogen-mixed gas leakage and jet fire test method comprises: S1, installing a leakage device on a pipeline, and evacuating the pipeline by a vacuum pump; S2, calculating the leakage gas ratio under different mixing ratio conditions, opening the hydrogen cylinder and the natural gas tanker to inject gas into the pipeline until the indication of the pressure sensor reaches the preset pressure value, and stopping the gas injection; S3, leaking the gas cloud through the leakage device, observing the real-time image and data of the infrared camera and the gas concentration sensor, and completing the natural gas hydrogen-mixed leakage test; S4, igniting through an electric ignition device to cause the combustible gas leaking from the pipeline to explode, collecting the data of the pressure sensor, temperature sensor inside the pipeline and the armored thermocouple, gas concentration sensor, and thermal radiation sensor outside the pipeline through a data acquisition instrument, and at the same time, triggering the infrared camera through a computer to record the propagation process of the jet flame, and completing the natural gas hydrogen-mixed jet fire experiment.

[0020] The beneficial effects of the technical solution of the present invention are: the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing leakage devices of different sizes. The leakage / jet fire experiment is carried out on the leakage of the mixed gas by controlling the electric ignition device. The gas cloud leakage process is observed by an infrared camera or the shape and length of the jet fire are studied. The infrared camera is used to record the propagation process of gas leakage or jet flame when the pipeline leaks at high pressure. The armored thermocouple is used to study the temperature change of the gas cloud leaking from the pipeline, the gas concentration sensor is used to study the concentration distribution at different distances, and the concentration change of the escaped gas cloud is recorded. The thermal radiation sensor is used to study the thermal radiation at different distances and record the influence of flame radiation. The vacuum pump is used for vacuum treatment after the combustible gas leaks. The data acquisition instrument is used to collect data from the pressure sensor, temperature sensor inside the large-scale pipeline and the armored thermocouple, gas concentration sensor and thermal radiation sensor outside, and send the collected data to the computer.

[0021] Furthermore, after step S4, the following is included: S5, after the experiment is completed, when the reading of the pressure sensor drops to be equal to the atmospheric pressure, the leakage device is closed, and the vacuum pump is turned on to evacuate the pipeline.

[0022] The beneficial effect of adopting the above further technical solution is that before the leakage / jet fire test, there may be air or purge inert gas inside the pipeline. If these gases are not discharged, when the next leakage / jet fire test is carried out, the waste gas generated will interfere with the next test. The vacuum pump is used for vacuum treatment after the combustible gas leaks.

[0023] Furthermore, after step S5, the method includes: analyzing parameter characteristics of leakage / injection fire of natural gas-hydrogen mixed gas with different blending ratios based on the experimental purpose through the images and parameters transmitted to the computer.

[0024] The beneficial effect of adopting the above further technical solution is: by transmitting images and parameters to the computer, various parameter characteristics of natural gas hydrogen mixed gas leakage / jet fire with different blending ratios based on experimental purposes are analyzed to provide theoretical guidance for safe production.

[0025] Furthermore, in step S1, solenoid valves with different leakage apertures and pressure conditions and extension tubes of corresponding sizes are installed based on the experimental purpose; in step S2, the leakage gas ratio under different mixing ratio conditions is calculated by the partial pressure method.

[0026] The beneficial effect of adopting the above further technical solution is that the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing electromagnetic valves of different sizes. In order to protect the electromagnetic valve from the high temperature of the flame, an extension tube of the corresponding size is installed.

[0027] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device provided in an embodiment of the present invention.

[0029] Figure 2 A schematic flowchart of a large-scale natural gas hydrogen-blended gas leakage and jet fire testing method provided in an embodiment of the present invention.

[0030] Explanation of the accompanying drawings: 1. Gas injection valve; 2. Hydrogen cylinder; 3. Pressure sensor; 4. Temperature sensor; 5. Armored thermocouple; 6. Electric ignition electrode; 7. Extension tube; 8. Solenoid valve; 9. Natural gas tank truck; 10. Vacuum pump; 11. Pipeline; 12. Infrared camera; 13. Computer; 14. Data acquisition instrument; 15. Gas concentration sensor; 16. Thermal radiation sensor; 17. Bracket; 18. Electric ignition switch. DETAILED DESCRIPTION

[0031] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention but not to limit the scope of the present invention.

[0032] like Figure 1As shown, an embodiment of the present invention provides a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device, including: a hydrogen cylinder 2, a pressure sensor 3, a temperature sensor 4, an armored thermocouple 5, an electric ignition device, a leakage device, a natural gas tanker 9, a vacuum pump 10, a pipeline 11, an infrared camera 12, a computer 13, a data acquisition instrument 14, a gas concentration sensor 15, and a thermal radiation sensor 16. The hydrogen cylinder 2, the pressure sensor 3, the temperature sensor 4, the leakage device, the natural gas tanker 9, and the vacuum pump 10 are all connected to the pipeline 11, the armored thermocouple 5, the electric ignition device, the infrared camera 12, the gas concentration sensor 15, and the thermal radiation sensor 16 are all adjacent to the leakage device, the data acquisition instrument 14 is respectively connected to the pressure sensor 3, the temperature sensor 4, the armored thermocouple 5, the gas concentration sensor 15, and the thermal radiation sensor 16, and the infrared camera 12 and the data acquisition instrument 14 are both connected to the computer 13.

[0033] The beneficial effects of the technical solution of the present invention are: the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing leakage devices of different sizes. The leakage / jet fire experiment is carried out on the leakage of the mixed gas by controlling the electric ignition device. The gas cloud leakage process is observed by an infrared camera or the shape and length of the jet fire are studied. The infrared camera is used to record the propagation process of gas leakage or jet flame when the pipeline leaks at high pressure. The armored thermocouple is used to study the temperature change of the gas cloud leaking from the pipeline, the gas concentration sensor is used to study the concentration distribution at different distances, and the concentration change of the escaped gas cloud is recorded. The thermal radiation sensor is used to study the thermal radiation at different distances and record the influence of flame radiation. The vacuum pump is used for vacuum treatment after the combustible gas leaks. The data acquisition instrument is used to collect data from the pressure sensor, temperature sensor inside the large-scale pipeline and the armored thermocouple, gas concentration sensor and thermal radiation sensor outside, and send the collected data to the computer.

[0034] The pipeline 11 may be a large-scale pipeline, and the infrared camera 12 may be an infrared high-speed camera.

[0035] A large-scale natural gas hydrogen-blended gas leakage and jet fire test device and method provided in an embodiment of the present invention can be a large-scale natural gas hydrogen-blended pipeline leakage / jet fire test device and method, including a large pipeline (pipeline 11) with an external pipeline and a leakage device, a high-speed photography device (infrared camera 12), a thermal radiation sensor and a gas concentration sensor. The large pipeline is connected to the hydrogen cylinder and the natural gas tank truck respectively through the gas injection valve, and the temperature sensor and the pressure sensor are connected by threads. The leakage port is installed with solenoid valves of different sizes to achieve the function of leakage of different pressures and different leakage diameters. At the same time, in order to protect the solenoid valve from the high temperature of the flame, an extension tube of corresponding size is installed. The leakage of the mixed gas is subjected to a leakage / jet fire experiment by controlling the arc ignition device (electric ignition device). The gas cloud leakage process is observed by using an infrared high-speed photography device (infrared camera) or the jet fire shape and length are studied. The armored thermocouple is used to study the temperature change of the gas cloud directly above the pipeline, the gas concentration sensor is used to study the concentration distribution at different distances, and the thermal radiation sensor is used to study the thermal radiation at different distances.

[0036] An embodiment of the present invention provides a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device, which can be a large-scale natural gas hydrogen-blended pipeline leakage / jet fire experimental device, including: a large-scale pipeline (pipeline 11) with an external pipeline and a leakage device, an electric ignition device, a high-speed infrared photography device (infrared camera), a temperature sensor, a thermal radiation sensor and a gas concentration sensor.

[0037] The pipeline is a large-scale pipeline, which is connected to a pressure sensor and a temperature sensor, and is externally connected to a hydrogen cylinder, a natural gas tanker and a vacuum pump.

[0038] Optionally, a large-scale pipeline is connected to a pressure sensor through a thread to measure the pressure value during gas injection in a confined space.

[0039] Optionally, the large-scale pipeline is connected to a temperature sensor through a thread to measure the temperature value during gas injection in the closed space.

[0040] Optionally, it also includes a hydrogen cylinder, which is connected to the interior of the large-scale pipeline through a gas injection valve.

[0041] Optionally, a natural gas tanker is also included, which is connected to the interior of the large-scale pipeline through a gas injection valve.

[0042] Optionally, the large-scale pipeline is connected to a vacuum pump through a gas injection valve, and the vacuum pump can be used for vacuuming after the combustible gas leaks.

[0043] Optionally, it also includes an electric ignition device, a data acquisition instrument and a computer, and the computer is connected to the data acquisition instrument.

[0044] The data acquisition instrument is used to collect data from pressure sensors, temperature sensors inside large-scale pipelines, as well as external armored thermocouples, gas concentration sensors and thermal radiation sensors, and send the collected data to a computer.

[0045] The electric ignition device is used to control the electric ignition electrode for ignition.

[0046] The computer is used to receive the data collected by the data acquisition instrument and send trigger instructions to the pressure sensor, temperature sensor, infrared high-speed photography device, armored thermocouple, gas concentration sensor, and thermal radiation sensor.

[0047] Optionally, an infrared high-speed camera (infrared camera) is also included. The infrared high-speed camera is used to record the propagation process of gas leakage or jet flame when a large-scale pipeline high-pressure leak occurs. The infrared high-speed camera is connected to a computer.

[0048] Furthermore, the pressure sensor 3 and the temperature sensor 4 are connected to the pipe 11 through threads, and the number of the gas concentration sensor 15 and the thermal radiation sensor 16 are both multiple, and the multiple gas concentration sensors 15 and the multiple thermal radiation sensors 16 are respectively arranged in sequence along the adjacent leakage device toward the periphery.

[0049] The beneficial effects of adopting the above further technical solution are: using the gas concentration sensor to study the concentration distribution at different distances, and using the thermal radiation sensor to study the thermal radiation at different distances. The pipeline is connected to the pressure sensor through a thread to measure the pressure value when the gas is injected into the confined space. The pipeline is connected to the temperature sensor through a thread to measure the temperature value when the gas is injected into the confined space.

[0050] Furthermore, the hydrogen cylinder 2 , the natural gas tanker 9 and the vacuum pump 10 are all connected to the pipeline 11 via the gas injection valve 1 .

[0051] The beneficial effect of adopting the above further technical solution is that the provision of the gas injection valve facilitates opening and closing of the corresponding pipeline according to actual needs.

[0052] Furthermore, the leakage device comprises: an extension tube 7 and a solenoid valve 8 , the solenoid valve 8 is connected to the pipeline 11 , and the extension tube 7 is connected to the solenoid valve 8 .

[0053] The beneficial effect of adopting the above further technical solution is that the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing electromagnetic valves of different sizes. In order to protect the electromagnetic valve from the high temperature of the flame, an extension tube of the corresponding size is installed.

[0054] Furthermore, the armored thermocouple 5 and the electric ignition device are both installed on a bracket 17, and the bracket 17 is adjacent to the leakage device; the bracket 17 is a V-shaped or L-shaped structure, and there are multiple armored thermocouples 5, and the multiple armored thermocouples 5 are arranged in sequence on the bracket 17 along the adjacent leakage device toward the periphery.

[0055] The beneficial effects of adopting the above further technical solution are: using armored thermocouples to study the temperature change of the gas cloud directly above the pipeline, and using the bracket to control the ignition position, so as to obtain the combustion and explosion parameters of the jet flame at different ignition positions.

[0056] Furthermore, the electric ignition device includes: an electric ignition electrode 6 and an electric ignition switch 18 , and the electric ignition electrode 6 is connected to the electric ignition switch 18 .

[0057] The beneficial effect of adopting the above further technical solution is that the electric ignition device is used to control the electric ignition electrode to ignite. The leakage / jet fire test of the mixed gas is carried out by controlling the electric ignition device.

[0058] The advantages of the present invention are that it can not only realize the leakage phenomenon of natural gas mixed with hydrogen at different mixing ratios under different pressures, discharge diameters and other conditions under large-scale conditions, but also can observe and record the jet fire phenomenon. At the same time, it further provides a reference range of safe distance for the diffusion of gas cloud and jet fire accidents of natural gas mixed with hydrogen leakage in the actual production process.

[0059] like Figure 1 As shown, the leakage / jet fire test device (large-scale natural gas hydrogen-mixed gas leakage and jet fire test device) of the present invention includes: a pipeline 11, which is connected to the pressure sensor 3 and the temperature sensor 4 through threads, and is connected to the hydrogen cylinder 2, the natural gas tanker 9, and the vacuum pump 10 through the gas injection valve 1. Here, it should be noted that when the leakage / jet fire test of natural gas hydrogen-mixed gas with different blending ratios is actually carried out, the pressure values ​​of different gases need to be calculated for different experimental requirements, and the gas injection situation is judged by the value of the pressure sensor 3. After the experiment is over, vacuum should be evacuated, and vacuum can be evacuated by opening the gas injection valve 1 corresponding to the vacuum pump 10.

[0060] The pipeline 11 is provided with a leakage device, which includes: a solenoid valve 8 and an extension pipe 7. The base of the solenoid valve 8 is connected to the large-scale pipeline (pipeline 11) by welding. Solenoid valves 8 and extension pipes 7 with different leakage apertures and pressure-bearing states can be installed according to experimental working conditions.

[0061] In some embodiments, Figure 1As shown, the leakage / jet fire test device (large-scale natural gas hydrogen-blended gas leakage and jet fire test device) of the present invention is connected to the vacuum pump 10 through the gas injection valve 1. Before the leakage / jet fire test is performed, there may be air or purge inert gas inside the large-scale pipeline. If these gases are not discharged, when the next leakage / jet fire test is performed, the waste gas generated will interfere with the next test.

[0062] An electric ignition electrode 6 and an armored thermocouple 5 are provided on the bracket 17, which can be switched on and off by an electric ignition switch 18. If ignition is not required, the mixed gas escape phenomenon is observed by an infrared high-speed photography device (infrared camera 12). If a jet flame is to be observed, the jet should be ignited by an electric ignition device to form a jet flame.

[0063] In some embodiments, Figure 1 As shown, the spontaneous combustion / jet fire experimental device (large-scale natural gas hydrogen-blended gas leakage and jet fire test device) of the present invention also includes: a data acquisition instrument 14 and a computer 13, and the computer 13 is respectively connected to the data acquisition instrument 14 and the infrared high-speed photography device (infrared camera 12). The data acquisition instrument 14 is connected to the internal pressure sensor 3 and the temperature sensor 4, and sends the collected data to the computer 13, which is used to realize the real-time monitoring of the pressure and temperature values ​​in the large-scale pipeline (pipeline 11). The data acquisition instrument 14 is also connected to the external armored thermocouple 5, the gas concentration sensor 15, and the thermal radiation sensor 16, and sends the collected data to the computer 13, which is used to realize the real-time monitoring of the external temperature, concentration and thermal radiation values ​​after the gas cloud escapes or is ignited. The infrared high-speed photography device (infrared camera 12) sends real-time images and data to the computer 1, which is used to observe the shape and temperature characteristics of the leaking gas cloud or the ignited flame.

[0064] The electric ignition switch 18 is used to control the electric ignition electrode 6 for ignition. The bracket 17 can be used to control the ignition position, so as to obtain the combustion parameters of the jet flame at different ignition positions.

[0065] like Figure 2As shown, in addition, the present invention also provides a large-scale natural gas hydrogen-mixed gas leakage and jet fire test method, based on any one of the large-scale natural gas hydrogen-mixed gas leakage and jet fire test devices described above, the large-scale natural gas hydrogen-mixed gas leakage and jet fire test method includes: S1, installing a leakage device on the pipeline, and vacuumizing the pipeline through a vacuum pump; S2, calculating the leakage gas ratio under different mixing ratio conditions, opening the hydrogen cylinder and the natural gas tanker to inject gas into the pipeline until the indication of the pressure sensor reaches the preset pressure value, and stopping the gas injection; S3, leaking the gas cloud through the leakage device, observing the real-time image and data of the infrared camera and the gas concentration sensor, and completing the natural gas hydrogen-mixed leakage test; S4, igniting through an electric ignition device to cause the combustible gas leaking from the pipeline to explode, collecting the data of the pressure sensor, temperature sensor inside the pipeline and the armored thermocouple, gas concentration sensor, and thermal radiation sensor outside the pipeline through a data acquisition instrument, and at the same time, triggering the infrared camera through a computer to record the propagation process of the jet flame, and completing the natural gas hydrogen-mixed jet fire experiment.

[0066] The beneficial effects of the technical solution of the present invention are: the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing leakage devices of different sizes. The leakage / jet fire experiment is carried out on the leakage of the mixed gas by controlling the electric ignition device. The gas cloud leakage process is observed by an infrared camera or the shape and length of the jet fire are studied. The infrared camera is used to record the propagation process of gas leakage or jet flame when the pipeline leaks at high pressure. The armored thermocouple is used to study the temperature change of the gas cloud leaking from the pipeline, the gas concentration sensor is used to study the concentration distribution at different distances, and the concentration change of the escaped gas cloud is recorded. The thermal radiation sensor is used to study the thermal radiation at different distances and record the influence of flame radiation. The vacuum pump is used for vacuum treatment after the combustible gas leaks. The data acquisition instrument is used to collect data from the pressure sensor, temperature sensor inside the large-scale pipeline and the armored thermocouple, gas concentration sensor and thermal radiation sensor outside, and send the collected data to the computer.

[0067] The embodiment of the present invention provides a large-scale natural gas hydrogen-mixed gas leakage and jet fire test method, which can be an operation method of a natural gas hydrogen-mixed gas leakage / jet fire test device with different blending ratios under large-scale conditions, and is used for the above-mentioned natural gas hydrogen-mixed gas leakage and jet fire phenomenon research with different blending ratios, including the following steps:

[0068] Install solenoid valves with different leakage diameters and pressure conditions and corresponding extension pipes based on the experimental purpose. Turn on the vacuum pump to evacuate the large-scale pipeline.

[0069] Trigger instructions are sent through a computer to the pressure sensor, temperature sensor inside the large-scale pipeline, as well as the external armored thermocouple, gas concentration sensor, thermal radiation sensor and infrared high-speed photography equipment, so that the pressure sensor and temperature sensor can record the pressure and temperature fluctuations in the large-scale pipeline. The infrared high-speed camera is used to record the propagation process of gas leakage or jet flame when the large-scale pipeline has a high-pressure leak. The armored thermocouple records the temperature change of the leaking gas cloud in the large-scale pipeline. The concentration sensor records the concentration change of the escaped gas cloud. The thermal radiation sensor records the impact of flame radiation.

[0070] The leakage gas ratio under different mixing ratio conditions is calculated by partial pressure method. Hydrogen gas and natural gas tank trucks are respectively introduced through the gas injection valve until the internal pressure of the large-scale pipeline reaches the preset value and the air intake is stopped.

[0071] The ignition device controls the electric ignition electrode to ignite so that the combustible gas leaking from the large-scale pipeline will explode. The data acquisition instrument collects data from the internal pressure sensor, temperature sensor and the external armored thermocouple, gas concentration sensor, and thermal radiation sensor. At the same time, the computer triggers the infrared high-speed camera to record the propagation process of the jet flame.

[0072] After the experiment is completed, when the pressure sensor reading drops to the same level as the atmospheric pressure, close the solenoid valve and evacuate the large-scale pipeline through the gas injection valve;

[0073] Repeat the above experimental steps to conduct the experiment.

[0074] As can be seen from the above, the large-scale natural gas hydrogen-blended pipeline leakage / jet fire experimental device and its operation method provided by the present invention, a large-scale pipeline with a leakage device and a high-speed photography device, and a physical property measurement device, overcome the problem in the related art that it is impossible to explore the research on characteristic parameters such as high-pressure leakage / jet flame of natural gas hydrogen-blended mixed gas with different blending ratios under actual production conditions, and further provide a reference range of safe distance for the diffusion of gas clouds and jet fire accidents caused by leakage of natural gas hydrogen-blended in actual production processes.

[0075] Furthermore, after step S4, the following is included: S5, after the experiment is completed, when the reading of the pressure sensor drops to be equal to the atmospheric pressure, the leakage device is closed, and the vacuum pump is turned on to evacuate the pipeline.

[0076] The beneficial effect of adopting the above further technical solution is that before the leakage / jet fire test, there may be air or purge inert gas inside the pipeline. If these gases are not discharged, when the next leakage / jet fire test is carried out, the waste gas generated will interfere with the next test. The vacuum pump is used for vacuum treatment after the combustible gas leaks.

[0077] Furthermore, after step S5, the method includes: analyzing parameter characteristics of leakage / injection fire of natural gas-hydrogen mixed gas with different blending ratios based on the experimental purpose through the images and parameters transmitted to the computer.

[0078] The beneficial effect of adopting the above further technical solution is: by transmitting images and parameters to the computer, various parameter characteristics of natural gas hydrogen mixed gas leakage / jet fire with different blending ratios based on experimental purposes are analyzed to provide theoretical guidance for safe production.

[0079] Furthermore, in step S1, solenoid valves with different leakage apertures and pressure conditions and extension tubes of corresponding sizes are installed based on the experimental purpose; in step S2, the leakage gas ratio under different mixing ratio conditions is calculated by the partial pressure method.

[0080] The beneficial effect of adopting the above further technical solution is that the leakage port can realize the function of leakage of different pressures and different leakage diameters by installing electromagnetic valves of different sizes. In order to protect the electromagnetic valve from the high temperature of the flame, an extension tube of the corresponding size is installed.

[0081] The embodiment of the present invention also provides an operating method of a large-scale natural gas hydrogen-mixed pipeline leakage / jet fire test device (large-scale natural gas hydrogen-mixed gas leakage and jet fire test method). Based on the above-mentioned combustion and explosion characteristics experimental device (large-scale natural gas hydrogen-mixed gas leakage and jet fire test device), the operating method includes the following steps:

[0082] Based on the experimental purpose, electromagnetic valves 8 and extension pipes 7 with different leakage apertures and pressure conditions are installed, and the leakage device is tightly fitted with the pipeline 11 through welding. The vacuum pump 10 is turned on to evacuate the large-scale pipeline (pipeline 11).

[0083] The leakage gas ratio under different mixing ratio conditions is calculated by partial pressure method. Hydrogen gas and natural gas tank trucks are respectively inlet through the gas injection valve 1 until the indication of the pressure sensor 3 reaches the preset pressure value, and the intake is stopped.

[0084] If a natural gas hydrogen-blended leakage test is conducted, the gas cloud leakage is conducted by controlling the solenoid valve 8 , and the real-time images and data of the infrared high-speed photography device (infrared camera 12 ) and the gas concentration sensor 15 are observed.

[0085] If a natural gas hydrogen-blended jet fire experiment is conducted, the electric ignition switch 18 is used to control the electric ignition electrode 6 to ignite so that the combustible gas leaking from a large-scale pipeline can explode. The data acquisition instrument 14 collects data from the internal pressure sensor 3, the temperature sensor 4 and the external armored thermocouple 5, the gas concentration sensor 15, and the thermal radiation sensor 16. At the same time, the computer 13 triggers the infrared high-speed camera (infrared camera 12) to enable the infrared high-speed camera to record the propagation process of the jet flame.

[0086] After the experiment is completed, when the reading of the pressure sensor 3 drops to be equal to the atmospheric pressure, the solenoid valve 8 is closed, and the vacuum pump 10 is turned on to evacuate the large-scale pipeline (pipeline 11) through the gas injection valve 1.

[0087] Repeat the above experimental steps to conduct the experiment.

[0088] Finally, by transmitting the images and parameters to the computer 13, various parameter characteristics of the leakage / injection fire of the natural gas-hydrogen mixed gas with different blending ratios based on the experimental purpose are analyzed to provide theoretical guidance for safe production.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device, characterized in that: include: Hydrogen cylinder, pressure sensor, temperature sensor, armored thermocouple, electric ignition device, leakage device, natural gas tanker, vacuum pump, pipeline, infrared camera, computer, data acquisition instrument, gas concentration sensor, thermal radiation sensor, the hydrogen cylinder, the pressure sensor, the temperature sensor, the leakage device, the natural gas tanker, the vacuum pump are all connected to the pipeline, the armored thermocouple, the electric ignition device, the infrared camera, the gas concentration sensor and the thermal radiation sensor are all adjacent to the leakage device, the data acquisition instrument is respectively connected to the pressure sensor, the temperature sensor, the armored thermocouple, the gas concentration sensor and the thermal radiation sensor, and the infrared camera and the data acquisition instrument are both connected to the computer.

2. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to claim 1, characterized in that: The pressure sensor and the temperature sensor are both connected to the pipeline via threads. The number of the gas concentration sensor and the thermal radiation sensor are both multiple, and the multiple gas concentration sensors and the multiple thermal radiation sensors are arranged in sequence toward the periphery along the adjacent leakage device.

3. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to claim 1, characterized in that: The hydrogen cylinder, the natural gas tanker and the vacuum pump are all connected to the pipeline via a gas injection valve.

4. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to claim 1, characterized in that: The leakage device comprises: an extension tube and a solenoid valve, wherein the solenoid valve is connected to the pipeline, and the extension tube is connected to the solenoid valve.

5. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to claim 1, characterized in that: The armored thermocouple and the electric ignition device are both installed on a bracket, and the bracket is adjacent to the leakage device; the bracket is a V-shaped or L-shaped structure, and there are multiple armored thermocouples, which are arranged on the bracket in sequence along the adjacent leakage device toward the periphery.

6. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to claim 1, characterized in that: The electric ignition device comprises an electric ignition electrode and an electric ignition switch, wherein the electric ignition electrode is connected to the electric ignition switch.

7. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing method, characterized in that: Based on a large-scale natural gas hydrogen-blended gas leakage and jet fire testing device according to any one of claims 1 to 6 above, a large-scale natural gas hydrogen-blended gas leakage and jet fire testing method comprises: S1. Install a leakage device on the pipeline and evacuate the pipeline using a vacuum pump; S2. Calculate the leakage gas ratio under different mixing ratio conditions, open the hydrogen cylinder and the natural gas tanker to inject gas into the pipeline until the pressure sensor reading reaches the preset pressure value, and stop injecting gas; S3. Conduct gas cloud leakage through the leakage device, observe the real-time images and data of the infrared camera and gas concentration sensor, and complete the natural gas hydrogen-blended leakage test; S4. Ignite the combustible gas leaking from the pipeline by using an electric ignition device to cause it to explode. Use a data acquisition instrument to collect data from the pressure sensor, temperature sensor inside the pipeline and the armored thermocouple, gas concentration sensor, and thermal radiation sensor outside. At the same time, use a computer to trigger an infrared camera to record the propagation process of the jet flame and complete the natural gas hydrogen-blended jet fire experiment.

8. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing method according to claim 7, characterized in that: The process after step S4 includes: S5, after the experiment is completed, when the reading of the pressure sensor drops to be equal to the atmospheric pressure, the leakage device is closed, and the vacuum pump is turned on to evacuate the pipeline.

9. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing method according to claim 8, characterized in that: The process after step S5 includes: analyzing parameter characteristics of leakage / injection fire of natural gas-hydrogen mixed gas with different blending ratios based on the experimental purpose through the images and parameters transmitted to the computer.

10. A large-scale natural gas hydrogen-blended gas leakage and jet fire testing method according to claim 7, characterized in that: In step S1, solenoid valves with different leakage apertures and pressure conditions and extension tubes of corresponding sizes are installed based on the experimental purpose; in step S2, the leakage gas ratio under different mixing ratio conditions is calculated by the partial pressure method.

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