A simulation device for hydrogen recombiner natural circulation flow experiment

Abstract

The application relates to a simulation device for hydrogen recombiner natural circulation flow experiment, belonging to the technical field of nuclear accident treatment, which comprises a hydrogen recombiner flow channel simulation body, which comprises a shell, the lower part of the shell is provided with an air inlet channel, the upper part is provided with an air outlet grid; the inner side of the shell is provided with a porous medium hydrogen gas burner group at the lower part, an air injection pipeline, a hydrogen injection pipeline, a water cooling pipeline water injection pipe and a water cooling pipeline drainage pipe are located around the porous medium hydrogen gas burner group and are communicated with the porous medium hydrogen gas burner group through different connecting pipes, air and hydrogen are injected into the porous medium hydrogen gas burner group through the air injection pipeline and the hydrogen injection pipeline respectively, when the hydrogen concentration in the porous medium hydrogen gas burner group meets the combustion condition, hydrogen-air mixed gas is combusted in the porous medium hydrogen gas burner group to release a large amount of heat. The application can avoid the risk brought by the hydrogen recombiner experiment in a real hydrogen environment and can also avoid the defect of high power when electric heating is used to simulate the hydrogen recombiner.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear accident treatment, and in particular relates to a simulation device for a natural circulation flow experiment of a hydrogen recombiner. Background Art

[0002] The hydrogen recombiner is a device used to eliminate hydrogen in the containment after a serious accident in a nuclear power plant. It is widely used in domestic nuclear power plants. It uses catalytic recombination to cause hydrogen and oxygen to undergo a recombination reaction, thereby eliminating hydrogen at a low hydrogen concentration and avoiding threats to the integrity of the containment due to hydrogen combustion and explosion.

[0003] After the catalytic reaction occurs in the hydrogen recombiner, a large amount of heat is released on the catalytic plate. This heat will drive the air to flow upward, thereby allowing more hydrogen-air mixed gas to enter the recombiner. The passive hydrogen recombiner utilizes this natural circulation process to passively eliminate the hydrogen in the containment without the need for any power drive.

[0004] During the development and testing of hydrogen recombiners, it is necessary to study the driving pressure head, natural circulation flow rate, and flow resistance of the hydrogen recombiner's natural circulation. To simulate the actual dehydrogenation process of a hydrogen recombiner, testing is usually required in an environment with a certain hydrogen concentration. However, a real hydrogen environment is somewhat dangerous and requires high safety and explosion prevention measures. Another testing method uses electric heating to simulate the heat release during the catalytic process of the hydrogen recombiner. However, this method cannot simulate the changes in the composition of the mixed gas after catalysis. It also requires a high electric heating power and strict test conditions. Taking a small recombiner as an example, under the operating conditions of a standard hydrogen concentration of 4%, the required electric heating power reaches 80kW. Summary of the Invention

[0005] In order to address the defects of the existing technology, the purpose of the present invention is to provide a simulation device for natural circulation flow experiments of hydrogen recombiners. The use of this simulation device can avoid the risks brought about by using a real hydrogen environment to conduct hydrogen recombiner experiments, and can also avoid the high power defect when using electric heating to simulate the hydrogen recombiner, providing a new experimental method for the natural circulation flow experiment of hydrogen recombiners.

[0006] In order to achieve the above purpose, a technical solution adopted by the present invention is:

[0007] A simulation device for a natural circulation flow experiment of a hydrogen recombiner, comprising:

[0008] A hydrogen recombiner flow channel simulation body, comprising a shell, an air inlet channel is provided at the lower portion of the shell, and an exhaust grille is provided at the upper portion of the shell;

[0009] A porous medium hydrogen burner group is provided at the lower inner portion of the shell, wherein one end of the porous medium hydrogen burner group for combustion is located inside the shell, and the other end is located outside the shell;

[0010] The air injection pipeline, hydrogen injection pipeline, water cooling pipeline water injection pipe and water cooling pipeline drainage pipe are located outside the hydrogen recombiner flow channel simulation body and around the porous medium hydrogen burner group, and are connected to the porous medium hydrogen burner group through different connecting pipes. Air and hydrogen are injected into the porous medium hydrogen burner group through the air injection pipeline and the hydrogen injection pipeline respectively;

[0011] The porous medium hydrogen burner group is provided with a plurality of hydrogen ignition devices. When the hydrogen concentration therein meets the combustion conditions, the hydrogen-air mixture burns in the porous medium hydrogen burner group. At the same time, a large amount of heat is released, which drives the air into the hydrogen recombiner flow channel simulation body from the air inlet channel and flows upward, and is discharged from the exhaust grille, forming a natural circulation.

[0012] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, the porous medium hydrogen burner group is composed of multiple groups of porous medium hydrogen burners arranged at certain intervals.

[0013] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, each of the porous medium hydrogen burners sequentially includes a hydrogen mixing chamber, a water cooling chamber and a porous medium combustion chamber.

[0014] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, an air injection pipe and a hydrogen injection pipe are provided on one side surface of the hydrogen mixing chamber, which are connected to the air injection pipeline and the hydrogen injection pipeline respectively.

[0015] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, the water-cooling chamber is adjacent to the hydrogen mixing chamber, and multiple capillary nozzles are arranged in parallel inside the water-cooling chamber, one end of the capillary nozzle is connected to the hydrogen mixing chamber, and the other end is connected to the porous medium combustion chamber.

[0016] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, a water-cooling inlet pipe is provided at the upper end of the water-cooling chamber, and a water-cooling drain pipe is provided at the lower end, which are respectively connected to the water-cooling pipeline water injection pipe and the water-cooling pipeline drain pipe.

[0017] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, a plurality of hydrogen ignition devices are arranged inside the porous medium combustion chamber to ignite the hydrogen-air mixture.

[0018] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, a plurality of temperature probes are further provided inside the porous medium combustion chamber for real-time monitoring of the temperature inside the porous medium combustion chamber.

[0019] Furthermore, in the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above, the porous medium combustion chamber is composed of a porous medium made of ceramic material.

[0020] Furthermore, the simulation device for the natural circulation flow experiment of the hydrogen recombiner as described above can adjust the heat release power of the simulation device at different hydrogen removal rates by adjusting the injection flow rate of hydrogen-air.

[0021] The simulation device for the natural circulation flow experiment of the hydrogen recombiner according to the present invention has the following significant technical effects:

[0022] This invention controls hydrogen-air combustion within a porous medium combustion chamber, avoiding the risks of overall hydrogen combustion and explosion that can occur in a real hydrogen environment. Compared to hydrogen flow experiments using electrical heating, this device generates greater heat, avoiding the limitations of high-power electric heating panels on experimental space. Furthermore, it ensures that the air composition within the hydrogen recombiner more closely resembles that of the air in a real hydrogen recombiner. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of a simulation device for a natural circulation flow experiment of a hydrogen recombiner provided in an embodiment of the present invention;

[0024] Figure 2 yes Figure 1 Schematic diagram of the structure of the porous medium hydrogen burner;

[0025] 1-Hydrogen recombiner flow channel simulation body, 2-Porous medium hydrogen burner group, 3-Air injection pipeline, 4-Hydrogen injection pipeline, 5-Water cooling pipeline water injection pipe, 6-Water cooling pipeline drainage pipe, 7-Hydrogen ignition device, 8-Temperature probe, 9-Shell, 10-Lower air inlet channel, 11-Upper exhaust grille, 12-Hydrogen mixing chamber, 13-Water cooling chamber, 14-Porous medium combustion chamber, 15-Air injection pipe, 16-Hydrogen injection pipe, 17-Capillary nozzle, 18-Water cooling inlet pipe, 19-Water cooling drainage pipe. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to specific embodiments and the accompanying drawings.

[0027] This invention is primarily used for natural circulation flow experiments in hydrogen recombiners. Compared to recombiner flow experiments conducted in a real hydrogen environment, this device controls hydrogen-air combustion within the burner, avoiding the risks of overall hydrogen combustion and explosion that can occur in a real hydrogen environment. Compared to hydrogen flow experiments using electrical heating, this device can generate greater heat, avoiding the limitations of high-power electric heating panels on the experimental site. Furthermore, it can ensure that the air composition within the hydrogen recombiner is closer to that of the air in a real hydrogen recombiner.

[0028] Figure 1 The schematic diagram of the structure of a simulation device for a natural circulation flow experiment of a hydrogen recombiner provided by an embodiment of the present invention is shown. The device mainly includes a hydrogen recombiner flow channel simulation body 1, a porous medium hydrogen burner group 2, an air injection pipeline 3, a hydrogen injection pipeline 4, a water cooling pipeline water injection pipe 5, a water cooling pipeline drainage pipe 6, and multiple hydrogen ignition devices 7. Among them:

[0029] The hydrogen recombiner flow channel simulation body 1 primarily consists of a shell 9, a lower air inlet channel 10, and an upper exhaust grille 11. The porous medium hydrogen burner group 2 is located below the shell 9, with one end for combustion located inside the shell 9 and the other end outside. The air injection line 3, hydrogen injection line 4, water cooling line injection pipe 5, and water cooling line drainage pipe 6 are located outside the hydrogen recombiner flow channel simulation body 1 and around the porous medium hydrogen burner group 2, connecting to the porous medium hydrogen burner group 2 through various connecting pipes. A plurality of hydrogen ignition devices 7 are provided inside the porous medium hydrogen burner group 2. Air and hydrogen are respectively injected into the porous medium hydrogen burner group 2 through the air injection pipeline 3 and the hydrogen injection pipeline 4. When the hydrogen concentration therein meets the combustion conditions, the hydrogen-air mixture burns in the porous medium hydrogen burner group 2. At the same time, a large amount of heat is released, which drives the air into the hydrogen recombiner flow channel simulation body 1 from the air inlet channel 10 and flows upward, and is discharged from the upper exhaust grille 11. Through this natural circulation process, the working process of the recombiner is simulated.

[0030] refer to Figure 2As shown, the porous medium hydrogen burner group 2 is composed of multiple groups of porous medium hydrogen burners arranged at a certain interval. Each porous medium hydrogen burner includes a hydrogen mixing chamber 12, a water cooling chamber 13 and a porous medium combustion chamber 14 in sequence. An air injection pipe 15 and a hydrogen injection pipe 16 are provided on one side of the hydrogen mixing chamber 12. They are connected to the air injection pipeline 3 and the hydrogen injection pipeline 4 respectively. The air and hydrogen in the pipeline are injected into the hydrogen mixing chamber 12 through the air injection pipe 15 and the hydrogen injection pipe 16 respectively for mixing. The water cooling chamber 13 is adjacent to the hydrogen mixing chamber 12. A plurality of capillary nozzles 17 are arranged in parallel inside the water cooling chamber 13. One end of the capillary nozzle 17 is connected to the hydrogen mixing chamber 12, and the other end is connected to the porous medium combustion chamber 14. The hydrogen-air mixture inside the hydrogen mixing chamber 12 enters the porous medium combustion chamber 14 through the capillary nozzle 17 for combustion.

[0031] A water-cooling inlet pipe 18 is provided at the upper end of the water-cooling chamber 13 and communicates with the water-cooling pipeline water injection pipe 5. A water-cooling drain pipe 19 is provided at the lower end of the water-cooling chamber 13 and communicates with the water-cooling pipeline drain pipe 6. Cooling water is injected into the water-cooling chamber 13 through the water-cooling inlet pipe 18 to prevent backflow of the hydrogen flame within the porous medium combustion chamber 14.

[0032] Specifically, multiple hydrogen ignition devices 7 are disposed within the porous medium combustion chamber 14 for igniting the hydrogen-air mixture. Multiple temperature probes 8 are also disposed within the porous medium combustion chamber 14 for real-time monitoring of the temperature within the combustion chamber 14. The porous medium combustion chamber 14 is composed of a porous ceramic medium and, during operation, enables the hydrogen-air mixture to fully combust, releasing a large amount of heat without generating flames.

[0033] The process of conducting the natural circulation flow experiment of the hydrogen recombiner using the above simulation device is as follows:

[0034] During the experimental preparation phase, water is first injected into the water-cooling chamber 13 through the water-cooling pipeline water injection pipe 5 and the water-cooling pipeline drainage pipe 6, and then nitrogen is injected through the air injection pipeline 3 to flush the oxygen in the pipeline to ensure safety.

[0035] At the beginning of the experiment, the hydrogen ignition device 7 and temperature probe 8 were energized. Then, a certain ratio of air and hydrogen was injected through the air injection line 3 and hydrogen injection line 4, respectively. When the hydrogen concentration within the porous medium hydrogen burner met the combustion conditions, the hydrogen-air mixture began to burn within the porous medium combustion chamber 14, releasing a large amount of heat.

[0036] By adjusting the hydrogen-air injection flow rate, the heat release power of the hydrogen recombiner at different hydrogen removal rates is simulated, and the flow characteristics in the hydrogen recombiner flow channel simulation body 1 are measured at the same time, thereby completing the natural circulation flow phenomenon test of the hydrogen recombiner.

[0037] This invention provides a simulation device for natural circulation flow experiments in a hydrogen recombiner. This device controls hydrogen-air combustion within the burner, avoiding the risks of overall hydrogen combustion and explosion that can occur in a real hydrogen environment. Compared to hydrogen flow experiments using electrical heating, this device generates greater heat, avoiding the limitations of high-power electric heating panels on the experimental site. Furthermore, it ensures that the air composition within the hydrogen recombiner more closely resembles that of the air in a real hydrogen recombiner.

[0038] The above embodiments are merely illustrative of the present invention, and the present invention may also be implemented in other specific ways or in other specific forms without departing from the gist or essential characteristics of the present invention. Therefore, the described embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is to be determined by the appended claims, and any variations equivalent to the intent and scope of the claims are intended to be within the scope of the present invention.

Claims

1. A simulation device for natural circulation flow experiment of hydrogen recombiner, characterized in that: The simulation device comprises: A hydrogen recombiner flow channel simulation body (1), comprising a shell (9), an air inlet channel (10) being provided at the lower portion of the shell (9), and an exhaust grille (11) being provided at the upper portion of the shell (9); A porous medium hydrogen burner group (2) is provided at the lower inner portion of the shell (9), wherein one end of the porous medium hydrogen burner group (2) for combustion is located inside the shell (9), and the other end is located outside the shell (9); The air injection pipeline (3), the hydrogen injection pipeline (4), the water cooling pipeline water injection pipe (5) and the water cooling pipeline drainage pipe (6) are located outside the hydrogen recombiner flow channel simulation body (1) and around the porous medium hydrogen burner group (2), and are connected to the porous medium hydrogen burner group (2) through different connecting pipes. Air and hydrogen are respectively injected into the porous medium hydrogen burner group (2) through the air injection pipeline (3) and the hydrogen injection pipeline (4); The porous medium hydrogen burner group (2) is provided with a plurality of hydrogen ignition devices (7). When the hydrogen concentration therein meets the combustion conditions, the hydrogen-air mixture burns in the porous medium hydrogen burner group (2). At the same time, a large amount of heat is released, driving the air from the air inlet channel (10) into the interior of the hydrogen recombiner flow channel simulation body (1) and flowing upwards, and being discharged from the exhaust grille (11), thereby forming a natural circulation. The porous medium hydrogen burner group (2) is formed by arranging a plurality of porous medium hydrogen burners at a certain interval, and each porous medium hydrogen burner includes a hydrogen mixing chamber (12), a water cooling chamber (13) and a porous medium combustion chamber (14) in sequence; the water cooling chamber (13) is adjacent to the hydrogen mixing chamber (12), and a plurality of capillary nozzles (17) are arranged in parallel inside the water cooling chamber (13); one end of the capillary nozzle (17) is connected to the hydrogen mixing chamber (12), and the other end is connected to the porous medium combustion chamber (14); the hydrogen-air mixed gas inside the hydrogen mixing chamber (12) enters the porous medium combustion chamber (14) through the capillary nozzle (17) and burns inside; by adjusting the injection flow rate of hydrogen-air, the heat release power of the simulation device at different hydrogen elimination rates is adjusted; The upper end of the water-cooling chamber (13) is provided with a water-cooling inlet pipe (18), and the lower end is provided with a water-cooling drainage pipe (19), which are respectively connected to the water-cooling pipeline water injection pipe (5) and the water-cooling pipeline drainage pipe (6). Cooling water is injected into the water-cooling chamber (13) through the water-cooling inlet pipe (18) to prevent the hydrogen flame inside the porous medium combustion chamber (14) from flowing back.

2. The simulation device for natural circulation flow experiment of hydrogen recombiner according to claim 1, characterized in that: An air injection pipe (15) and a hydrogen injection pipe (16) are provided on one side surface of the hydrogen mixing chamber (12), and are respectively connected to the air injection pipeline (3) and the hydrogen injection pipeline (4).

3. The simulation device for natural circulation flow experiment of hydrogen recombiner according to claim 2, characterized in that: A plurality of hydrogen ignition devices (7) are arranged inside the porous medium combustion chamber (14) and are used to ignite a hydrogen-air mixture.

4. The simulation device for natural circulation flow experiment of hydrogen recombiner according to claim 2, characterized in that: A plurality of temperature probes (8) are also provided inside the porous medium combustion chamber (14) for real-time monitoring of the temperature inside the porous medium combustion chamber (14).

5. The simulation device for natural circulation flow experiment of hydrogen recombiner according to claim 3 or 4, characterized in that: The porous medium combustion chamber (14) is composed of a porous medium made of ceramic material.

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