A fire-extinguishing performance evaluation method for fire-detecting tubes in live electrical control cabinets

Abstract

The present invention discloses a method for evaluating the fire extinguishing performance of a fire-detecting tube for an electrical control cabinet under energization. The method collects test data from fire extinguishing tests of different fire-detecting tube fire-extinguishing devices by simulating the fire scene of the electrical control cabinet under energization, selects six evaluation factors, namely, fire extinguishing spraying volume, flame extinguishing time, fire cooling rate, post-disaster burn rate, anti-reignition, and operating status of energized equipment, to construct a corresponding weight distribution system, and finally uses scoring and sorting to complete the comprehensive evaluation of the fire extinguishing performance of the fire-detecting tube. The advantages of the present invention are: it reproduces the real fire scene in the energized electrical cabinet and the start-up spraying and fire extinguishing process of the fire-detecting tube fire-extinguishing device; and forms a comprehensive evaluation system for the effectiveness and reliability of the fire-detecting tube fire-extinguishing through the six aspects of fire extinguishing spraying time, flame extinguishing time, fire cooling rate, post-disaster burn rate, reignition, and operating status of the energized equipment, scientifically and objectively compares the fire extinguishing performance of the fire-detecting tube fire-extinguishing device in a specific space of the electrical cabinet under energization, and realizes the best design selection for engineering applications.

Description

Technical Field

[0001] The invention belongs to the technical field of fire protection, and in particular relates to a method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet. Background Art

[0002] The fire detection tube is a new type of fire extinguishing device that integrates fire detection and fire extinguishing. It does not require power supply, special smoke sensors, temperature sensors and other detectors. It only needs to be arranged at the nearest potential fire point. Once a fire occurs, the fire detection tube will rupture due to heat, and use its own stored pressure to immediately release the fire extinguishing agent to implement point-to-point fire extinguishing. Therefore, the fire detection tube has the characteristics of self-starting, rapid detection and extinguishing of initial fires, and flexible arrangement. It has a wide range of application potentials in electrical control cabinet fire scenes. Scholars have conducted certain research on the basic performance, engineering design and application fields of fire detection tubes. Zhou Zhizhong et al. took different fire detection tubes to conduct explosion tests under oil bath and solid fire source, and studied the relationship between the filling pressure of the fire detection tube and the explosion hole. The results showed that the fire detection tube can only explode normally when the gas filling pressure reaches 1.0 MPa or above. Xiang Kun et al. selected heptafluoropropane and carbon dioxide as the fire extinguishing medium of the fire detection tube, and conducted experimental research on the fire extinguishing efficiency and post-fire toxicity of the large screen enclosed space of the railway dispatching station. The study showed that heptafluoropropane fire extinguishing is more efficient. Hu Xueyan and others designed and improved the application of fire detection tubes in electrical cabinets of thermal power plants. The study pointed out that fire detection tubes can suppress the fire source within 15 seconds after the fire extinguishing agent (such as carbon dioxide or heptafluoropropane) is sprayed, and the equipment is not damaged. Li Ke and others assembled a lithium-ion battery fire detection tube fire extinguishing device based on the fire detection tube fire extinguishing technology and used a new type of perfluorohexanone fire extinguishing agent. The experiment showed that when the fire detection tube was arranged directly above the battery, the fire was controlled within 5.6 seconds after the fire started. As the amount of fire extinguishing agent increased, the battery temperature could be significantly reduced to prevent the battery from reigniting and chain thermal runaway.

[0003] In summary, there has been some research on the application of fire detection tubes in various electrical scenarios, but the spraying methods and fire extinguishing agents of fire detection tubes are diverse, and the existing research is insufficient, especially the lack of fire extinguishing performance evaluation methods under live operating conditions.

[0004] The fire detection tube has two types of spraying methods: direct and indirect. Different types of fire extinguishing agents can be filled inside, such as carbon dioxide, heptafluoropropane, perfluorohexanone, etc. Therefore, it is a key issue to conduct fire extinguishing performance testing and evaluation based on actual electrical application scenarios and operating conditions, to achieve optimal selection, and to ensure the effectiveness and reliability of fire detection tube fire extinguishing. Summary of the invention

[0005] The purpose of the present invention is to provide a method for evaluating the fire extinguishing performance of a fire detector tube of an energized electrical control cabinet based on the above-mentioned deficiencies in the prior art. The evaluation method collects test data from fire extinguishing tests of different fire detector tube fire extinguishing devices and selects six evaluation factors to complete a comprehensive evaluation of the fire extinguishing performance of the fire detector tube.

[0006] The purpose of the present invention is achieved by the following technical solutions:

[0007] A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet, characterized in that the evaluation method comprises the following steps:

[0008] (S1) Design and establish a fire scenario: build a fire extinguishing protection space, place a fire source in the fire extinguishing protection space, and set a flame detector at the location of the fire source; set a temperature sensor and a fire detection tube fire extinguishing device in the fire extinguishing protection space, and a pressure sensor is connected to the bottle head valve of the fire detection tube fire extinguishing device; set a number of electrical equipment in the fire extinguishing protection space, and current and voltage sensors are connected to the non-fire electrical equipment; a video camera is set up outside the fire extinguishing protection space; the flame detector, the temperature sensor, the pressure sensor, the current and voltage sensor, and the video camera are all connected to the data acquisition system;

[0009] (S2) selecting an application method and a fire extinguishing agent for the fire detection tube fire extinguishing device;

[0010] (S3) starting the fire source, and waiting for the fire-detecting tube fire-extinguishing device to automatically start to spray fire extinguishing agent to extinguish the fire, and using the data acquisition system to collect data, including: the flame detector records the fire ignition time and the flame extinguishing time, the temperature sensor records the space temperature at different times in the fire extinguishing protection space, the pressure sensor records the internal release pressure change of the fire-detecting tube fire-extinguishing device, the current and voltage sensor records the operating status of the electrical equipment in real time, and the video camera records the video image of the electrical equipment and processes it to obtain the post-disaster burnout rate and re-ignition property;

[0011] (S4) acquiring the test data collected by the data acquisition system under the fire detection tube fire extinguishing device selected in step S2; then replacing the fire detection tube fire extinguishing devices in sequence and performing the fire extinguishing test in step S3, and deriving the test data of each fire extinguishing test from the data acquisition system;

[0012] (S5) Constructing a fire extinguishing effectiveness and reliability evaluation system based on the test data in step S4: Analyzing the test data to obtain evaluation factors, including the fire extinguishing spray volume α 1 , flame extinction time α 2 、Fire scene cooling rate α 3、Post-disaster burn rate α 4 、Resurgence resistance α 5 、Operation status of live equipment α 6 ; Establish the evaluation factor set {fire extinguishing spray volume α 1 , flame extinction time α 2 、Fire scene cooling rate α 3 、Post-disaster burn rate α 4 、Resurgence resistance α 5 、Operation status of live equipment α 6}; construct a review set {1 2 3 4 5 67 8 9 10}, where 10 is the best, 9 is the second, ..., 1 is the worst; determine the weight of each evaluation factor {β 1 β 2 β 3 β 4 β 5 β 6}, establish the judgment matrix Z;

[0013] (S6) Evaluate and score the six evaluation factors {δ 1,i δ 2,i δ 3,i δ 4,i δ 5,i δ 6,i}, according to the evaluation matrix Z and the calculation formula Ω i =δ i Z, calculate the comprehensive score of each fire detection tube fire extinguishing device.

[0014] The fire extinguishing protection space includes a platform outer cabinet and a cabinet arranged inside the platform outer cabinet. The electrical equipment is a server and is arranged on each tray of the cabinet at intervals from top to bottom; the fire source is arranged on the tray at the bottom of the cabinet to form a fire source oil pan; the temperature sensor and the flame detector are arranged above the fire source oil pan.

[0015] The fire source oil pan is provided with an ignition system, and the ignition system comprises a high-voltage package and a high-voltage ignition needle. The high-voltage package drives the high-voltage ignition needle to generate a high-voltage spark to ignite the fire source oil pan.

[0016] The fire-detecting tube fire-extinguishing device is composed of a fire-detecting tube and a fire-extinguishing agent bottle. The fire-detecting tube is extended and arranged along the height direction of the cabinet. The pressure sensor is arranged on the bottle head valve of the fire-extinguishing agent bottle.

[0017] The application mode of the fire-detecting tube fire-extinguishing device is direct or indirect; the fire-extinguishing agent is one of carbon dioxide, heptafluoropropane, and perfluorohexanone.

[0018] The advantages of the present invention are: through the test device and evaluation method established by the present invention, the real fire scene in the energized electrical cabinet and the startup and spraying fire extinguishing process of the fire detection tube fire extinguishing device are reproduced; and a comprehensive evaluation system for the effectiveness and reliability of the fire detection tube fire extinguishing is formed through six aspects: fire extinguishing spraying time, flame extinguishing time, fire scene cooling rate, post-disaster burn loss rate, re-ignition, and operating status of energized equipment. The fire extinguishing performance of the fire detection tube fire extinguishing device in a specific space of the electrical cabinet under energized operation is scientifically and objectively compared, and the optimal design selection for engineering applications is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the flow chart of the fire detection tube fire extinguishing performance evaluation method in the present invention;

[0020] Figure 2 It is a three-dimensional view of the overall structure of the test device in the present invention;

[0021] Figure 3 It is a side view of the overall structure of the test device in the present invention;

[0022] Figure 4 It is a schematic diagram of the structure of the ignition system in the present invention;

[0023] Figure 5 This is a view of the internal structure of the server in the present invention;

[0024] Figure 6 It is a system composition block diagram of the test device in the present invention. DETAILED DESCRIPTION

[0025] The features of the present invention and other related features are further described in detail below through embodiments in conjunction with the accompanying drawings to facilitate understanding by those skilled in the art:

[0026] like Figure 1-6 , the marks in the figure are: data acquisition console 1, pressure sensor 2, video camera 3, temperature sensor 4, cabinet 5, tray 6, server 7, exhaust fan 8, platform outer cabinet 9, transparent explosion-proof side panel 10, fire detection tube 11, fire extinguishing agent bottle 12, flame detector 13, fire source oil tray 14, high-voltage ignition needle 15, high-voltage package 16, cable 17, current and voltage sensor 18, data acquisition system 19, fire source 20, fire extinguishing protection space 21, fire detection tube fire extinguishing device 22.

[0027] Example: Figure 1-6 As shown, this embodiment specifically relates to a method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet, comprising the following steps:

[0028] (S1) Design and create fire scenarios:

[0029] Build a fire protection space 21, such as Figure 1 , 2 As shown, in this embodiment, the fire protection space 21 is composed of a platform outer cabinet 9 and a cabinet 5, and transparent explosion-proof side panels 10 are vertically sealed around and a door is reserved on one side to ensure real-time observation of the test process. The upper and lower bottom and top steel plates are tightly sealed, and an exhaust fan 8 is provided on the top of the platform outer cabinet 9 to start and exhaust smoke after the fire extinguishing test is completed; the cabinet 5 is placed inside the platform outer cabinet 9, and a plurality of trays 6 are arranged from top to bottom in the cabinet 5, and each electrical equipment is placed on the tray 6 accordingly. The electrical equipment here refers to the server 7, such as Figure 5 As shown, the server 5 is filled with cables 17 to simulate the internal circuits of the chassis, and is connected to a current and voltage sensor 18 to monitor the operating status of the live equipment in real time. A video camera 3 is set on the outside of the platform outer cabinet 9 to record the entire fire extinguishing test process, and the post-disaster burn rate and re-ignition are obtained through image processing.

[0030] An ignition source 20 is placed in the fire protection space 21. The ignition source 20 can be set to different types of ignition sources 20 such as a short circuit fire, a battery fire, and an oil pan fire. The ignition source 20 in this embodiment is an ignition source oil pan 14. The ignition source oil pan 14 is a tray 6 placed at the bottom of the cabinet 5 and contains flammable oil. An ignition system is arranged on the ignition source oil pan 14, including a high-voltage package 16 and a high-voltage ignition needle 15. The high-voltage package 16 drives the high-voltage ignition needle 15 to generate a high-voltage spark to ignite the ignition source oil pan 14. A temperature sensor 4 and a flame detector 13 are arranged above the ignition source oil pan 14. The temperature sensor 4 and the flame detector 13 are arranged above the ignition source oil pan 14. The device 4 is used to monitor the internal temperature change and obtain the fire scene cooling rate after the fire detection tube fire extinguishing device 22 sprays the fire extinguishing agent; the flame detector 13 is used to monitor the flame state in real time and determine the time of fire ignition and flame extinguishing; a fire detection tube fire extinguishing device is arranged in the cabinet 5, which is composed of a fire detection tube 11 and a fire extinguishing agent bottle 12 that are interconnected. The fire detection tube 11 is arranged along the height range of the cabinet 5. When the temperature reaches the starting temperature, the fire detection tube 11 opens the fire extinguishing agent bottle 12 to start the fire extinguishing system for fire extinguishing. The bottle head valve of the fire extinguishing agent bottle 12 is connected with a pressure sensor 2 to monitor the internal release pressure of the fire extinguishing agent bottle 12 in real time.

[0031] The aforementioned components (pressure sensor 2, video camera 3, temperature sensor 4, flame detector 13, current and voltage sensor 18) are all connected to the data acquisition system 19, which can record and store data in real time. The data acquisition system 19 runs on the data acquisition console 1.

[0032] (S2) Selecting the application method and fire extinguishing agent of the fire detection tube fire extinguishing device 22; the application method here refers to direct or indirect, such as directly spraying the fire extinguishing agent on the fire source, or indirectly extinguishing the fire by releasing inert gas to fill the fire extinguishing protection space; the fire extinguishing agent can be selected from carbon dioxide, heptafluoropropane, perfluorohexanone, etc.; it is replaced in sequence as needed during the test.

[0033] (S3) Turn on the video camera 3 for video acquisition, start the fire source 20, that is, ignite the fire source oil pan 14 through the ignition system to perform a fire extinguishing test; after the fire source oil pan 14 is ignited, the flame detector 13 detects the fire and uploads it to the data acquisition system, and the detection tube fire extinguishing device 22 automatically starts to spray the fire extinguishing agent to extinguish the fire source. In this process, the data acquisition system 19 is used to collect data, including: the flame detector 13 records the fire ignition time and the flame extinguishing time, the temperature sensor 4 records the space temperature at different times in the fire extinguishing protection space, the pressure sensor 2 records the internal release pressure change of the fire detection tube fire extinguishing device 22, the current and voltage sensor 18 records the operating status of the electrical equipment (i.e., the server 7) in real time, and the video camera 3 records the entire fire extinguishing test process and the video image of the server 7 and processes them to obtain the post-disaster burn rate and re-ignition.

[0034] (S4) Acquire the test data collected by the data acquisition system under the fire detection tube fire extinguishing device selected in step S2; then replace the fire detection tube fire extinguishing device 22 in turn and perform the fire extinguishing test in step S3, and export the test data of each fire extinguishing test from the data acquisition system 19.

[0035] (S5) Constructing a fire extinguishing effectiveness and reliability evaluation system based on the test data in step S4: Analyzing the test data to obtain evaluation factors, including the fire extinguishing spray volume α 1 , flame extinction time α 2 、Fire scene cooling rate α 3 、Post-disaster burn rate α 4 、Resurgence resistance α 5 、Operation status of live equipment α 6 ; Establish the evaluation factor set {fire extinguishing spray volume α 1 , flame extinction time α 2 、Fire scene cooling rate α 3 、Post-disaster burn rate α 4 、Resurgence resistance α 5 、Operation status of live equipment α 6}; construct a review set {1 2 3 4 5 67 8 9 10}, where 10 is the best, 9 is the second, ..., 1 is the worst; determine the weight of each evaluation factor {β 1 β 2 β 3 β 4β 5 β 6}, establish the judgment matrix Z;

[0036] (S6) Evaluate and score the six evaluation factors {δ 1,i δ 2,i δ 3,i δ 4,i δ 5,i δ 6,i}, according to the evaluation matrix Z and the calculation formula Ω i =δ i Z, calculate the comprehensive score Ω of each fire detection tube fire extinguishing device i . For the comprehensive score Ω i Sort from high to low and select the fire detection tube fire extinguishing device with the best fire extinguishing performance and the most reliable system as the best technical selection for the project.

[0037] According to the evaluation method in this embodiment, 8 types of fire detection tubes coded A, B, C, D, E, F, G, and H are selected as fire extinguishing protection devices for live electrical cabinets. Fire extinguishing experiments are carried out on different fire detection tubes according to the above experimental method. Experimental data such as fire extinguishing amount, space temperature, injection pressure, current voltage, and fire source extinguishing time are recorded. Then, each evaluation factor is ranked and assigned a value according to the above evaluation method. Since the flame extinguishing time and the fire scene cooling rate have a significant impact on the fire extinguishing efficiency of live equipment with the fire detection tube, their weights are all taken as 0.3, and the other parameters are 0.1, and an evaluation matrix is ​​established, as shown in Table 1.

[0038] Table 1 Comprehensive evaluation matrix for fire detection tube protection of live electrical cabinets:

[0039]

[0040] From Table 1, we can see that the three types of fire detection tubes with better fire extinguishing performance and higher reliability are G, B, and D, respectively. Therefore, it is recommended that G is the best technical selection for the project.

[0041] The beneficial effect of this embodiment is that the test device and evaluation method established in this embodiment reproduce the real fire scene in the live electrical cabinet and the start-up spraying and extinguishing process of the fire-detecting tube fire extinguishing device. A comprehensive evaluation system for the effectiveness and reliability of the fire-detecting tube fire extinguishing is formed through six aspects: fire-extinguishing spraying time, flame extinguishing time, fire scene cooling rate, post-disaster burn rate, re-ignition, and live equipment operation status. The fire-extinguishing performance of the fire-detecting tube fire extinguishing device in the specific space of the electrical cabinet under live operation is scientifically and objectively compared, and the optimal design selection for engineering applications is achieved.

Claims

1. A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet, characterized in that The evaluation method comprises the following steps: (S1) Design and establish a fire scenario: build a fire extinguishing protection space, place a fire source in the fire extinguishing protection space, and set a flame detector at the location of the fire source; set a temperature sensor and a fire detection tube fire extinguishing device in the fire extinguishing protection space, and a pressure sensor is connected to the bottle head valve of the fire detection tube fire extinguishing device; set a number of electrical equipment in the fire extinguishing protection space, and current and voltage sensors are connected to the non-fire electrical equipment; a video camera is set up outside the fire extinguishing protection space; the flame detector, the temperature sensor, the pressure sensor, the current and voltage sensor, and the video camera are all connected to the data acquisition system; (S2) selecting an application method and a fire extinguishing agent for the fire detection tube fire extinguishing device; (S3) starting the fire source, and waiting for the fire-detecting tube fire-extinguishing device to automatically start to spray fire extinguishing agent to extinguish the fire, and using the data acquisition system to collect data, including: the flame detector records the fire ignition time and the flame extinguishing time, the temperature sensor records the space temperature at different times in the fire extinguishing protection space, the pressure sensor records the internal release pressure change of the fire-detecting tube fire-extinguishing device, the current and voltage sensor records the operating status of the electrical equipment in real time, and the video camera records the video image of the electrical equipment and processes it to obtain the post-disaster burnout rate and re-ignition property; (S4) acquiring the test data collected by the data acquisition system under the fire detection tube fire extinguishing device selected in step S2; then replacing the fire detection tube fire extinguishing devices in sequence and performing the fire extinguishing test in step S3, and deriving the test data of each fire extinguishing test from the data acquisition system; (S5) Constructing a fire extinguishing effectiveness and reliability evaluation system according to the test data in step S4: Analyze the test data to obtain evaluation factors, including fire extinguishing spraying volume α1, flame extinguishing time α2, fire cooling rate α3, post-disaster burn rate α4, anti-reignition α5, live equipment operating status α6; Establishing an evaluation factor set {fire extinguishing spraying volume α1, flame extinguishing time α2, fire cooling rate α3, post-disaster burn rate α4, anti-reignition α5, live equipment operating status α6}; Constructing a comment set {1 2 3 4 5 6 7 89 10}, where 10 is the best, 9 is the second, ..., 1 is the worst; Determine the weight of each evaluation factor {β1 β2 β3 β4 β5 β6}, and establish a judgment matrix Z; (S6) Evaluate and score the six evaluation factors {δ 1,i δ 2,i δ 3,i δ 4,i δ 5,i δ 6,i }, according to the evaluation matrix Z and the calculation formula Ω i =δ i Z, calculate the comprehensive score Ω of each fire detection tube fire extinguishing device i .

2. A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet according to claim 1, characterized in that The fire extinguishing protection space includes a platform outer cabinet and a cabinet arranged inside the platform outer cabinet. The electrical equipment is a server and is arranged on each tray of the cabinet at intervals from top to bottom; the fire source is arranged on the tray at the bottom of the cabinet to form a fire source oil pan; the temperature sensor and the flame detector are arranged above the fire source oil pan.

3. A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet according to claim 2, characterized in that The fire source oil pan is provided with an ignition system, and the ignition system includes a high-voltage package and a high-voltage ignition needle. The high-voltage package drives the high-voltage ignition needle to generate a high-voltage spark to ignite the fire source oil pan.

4. A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet according to claim 2, characterized in that The fire-detecting tube fire-extinguishing device is composed of a fire-detecting tube and a fire-extinguishing agent bottle. The fire-detecting tube is extended and arranged along the height direction of the cabinet. The pressure sensor is arranged on the bottle head valve of the fire-extinguishing agent bottle.

5. A method for evaluating the fire extinguishing performance of a fire detection tube of an energized electrical control cabinet according to claim 4, characterized in that The application mode of the fire-detecting tube fire-extinguishing device is direct or indirect; the fire-extinguishing agent is one of carbon dioxide, heptafluoropropane, and perfluorohexanone.

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