A wood smoldering water spray extinguishing experiment testing device

Abstract

The present application belongs to the technical field of forest fire protection, and specifically relates to a wood smoldering water spraying fire extinguishing experimental testing device. The device comprises a hollow columnar heating barrel, a fuel fixing support and a pressure regulator as a fire source simulation system. The heating barrel is open at one end, and a plurality of series silicon-carbon rods are arranged in the heating barrel. The silicon-carbon rods are connected with the pressure regulator. A fuel tray is arranged on the fuel fixing support, and the tray can be moved into or out of the heating barrel. The heating barrel can heat the fuel on the tray to simulate a smoldering fire source. A spray head is arranged above the tray as a water spraying system, and a water tank supplies water to the spray head. A heat flow sensor, a heat flow data acquisition instrument, a temperature sensor and a temperature data acquisition instrument are arranged as a measurement system. The two sensors are arranged in the hollow columnar heating barrel, and are respectively connected with the corresponding acquisition instruments to read the sensor data. The present application can effectively simulate various smoldering states, and facilitate subsequent experiments to obtain more comprehensive smoldering fire extinguishing data.

Description

Technical Field

[0001] The invention belongs to the technical field of forest fire protection, and in particular relates to a wood smoldering water spray fire extinguishing experimental testing device. Background Art

[0002] Wood is one of the most important forest vegetation and the primary fire load in forest fires. Extreme fire behaviors such as crown fires and flyfires are all fueled by wood. Smoldering is one of the most common forms of wood combustion during fires. The common practice of blowing out smoldering wood fires presents a significant risk of flyfire ignition and induced fires. However, effective fire suppression with water, under limited water supply conditions in the wild, remains a pressing challenge. Therefore, studying the critical states of smoldering wood fires extinguished by water under varying water supply intensities and durations is a hot topic in the field of safety engineering, particularly forest fire science.

[0003] Currently, there are almost no independently designed experimental devices for smoldering wood fire extinguishing by water spray. Similar experiments mostly use commercially available fire extinguishing water guns or fixed nozzles to extinguish fire loads specified in the standard. On the one hand, the specifications vary and are mainly large-sized. On the other hand, there is a great deal of arbitrariness in the control of injection and combustion parameters. Therefore, this type of test bench makes it difficult to carry out systematic experimental research on smoldering wood fire extinguishing by water under different combustion states, different injection parameters, multiple working conditions, and multiple factors.

[0004] In the process of extinguishing small-scale forest combustibles, direct current or spray fire extinguishing with water as the main method is the most important fire extinguishing method. The study of the characteristics of water extinguishing fire of smoldering wood belongs to the field of forest fire safety engineering and is also one of the current hot topics in fire science. It is necessary to design a water spray fire extinguishing experimental test device that can simulate the smoldering state of wood. Summary of the Invention

[0005] The purpose of the present invention is to provide a water spray fire extinguishing experimental test device with a simple structure that can effectively simulate the smoldering state of wood, so as to realize the systematic experimental research on the water extinguishing of smoldering wood fire under different combustion states, different spray parameters, multiple working conditions and multiple factors.

[0006] The wood smoldering water spray fire extinguishing experimental test device provided by the present invention comprises a fire source simulation system, a water spray system and a measurement system;

[0007] The fire source simulation system includes a hollow cylindrical heating barrel, a fuel fixing bracket and a pressure regulator;

[0008] The hollow cylindrical heating barrel is cylindrical and open at both ends; a pulley is provided at the bottom of the hollow cylindrical heating barrel;

[0009] The hollow cylindrical heating barrel is provided with a plurality of silicon carbon rods connected in series, and the silicon carbon rods are evenly arranged against the inner barrel wall; the positive and negative poles of the silicon carbon rods are connected in sequence to form a total positive and negative terminal; the total positive and negative terminals are connected to a voltage regulator disposed outside the barrel via connecting wires through pre-set wiring holes on the hollow cylindrical heating barrel body; the voltage regulator is also connected to a power supply;

[0010] A cylindrical quartz glass barrel is also provided in the hollow cylindrical heating barrel, which is coaxially arranged with the hollow cylindrical heating barrel, and the silicon carbon rod is located between the inner wall of the hollow cylindrical heating barrel and the outer wall of the quartz glass barrel;

[0011] The fuel fixing bracket is used to fix the fuel sample to be tested, and has a vertical floor rod and a horizontal rod connected thereto, and the horizontal rod is used to support the fuel sample; the open end of the hollow cylindrical heating barrel faces the horizontal rod, and the hollow cylindrical heating barrel is moved by a pulley so that the horizontal rod can be moved into or out of the hollow cylindrical heating barrel;

[0012] The water spray system includes a spray head, a flow meter, a switch valve and a water tank with a water pump;

[0013] The nozzle is arranged above the fuel fixing bracket through the nozzle bracket, the water spraying direction is toward the horizontal rod, and the nozzle is connected to the water pump of the water tank through a water pipe; the flow meter and the switch valve are arranged on the water pipe;

[0014] The measurement system includes a heat flow sensor, a heat flow data acquisition instrument, a temperature sensor and a temperature data acquisition instrument;

[0015] The heat flow sensor is connected to a heat flow data acquisition instrument. When the heat flow sensor is placed in the hollow cylindrical heating barrel, the heat flow data acquisition instrument collects instantaneous thermal radiation data of the hollow cylindrical heating barrel.

[0016] The temperature sensor is connected to a temperature data collector. When the temperature sensor is arranged on the fuel sample, the temperature gradient change data inside the fuel sample can be collected through the temperature data collector.

[0017] In the present invention, asbestos for heat insulation is further provided between the inner wall of the hollow cylindrical heating barrel and the silicon carbon rod to control the surface temperature of the hollow cylindrical heating barrel body and ensure safety during operation.

[0018] In the present invention, the nozzles adopt nozzles with various rated flow rates such as direct current nozzles or spray nozzles, which can be used interchangeably to simulate nozzles of different fire extinguishing equipment.

[0019] In the present invention, the nozzle bracket is height-adjustable, thereby adjusting the distance between the horizontal rod and the nozzle, that is, the distance between the fuel sample and the nozzle;

[0020] The height-adjustable structure may adopt a structure in which conventional-sized sleeves are nested and telescopic.

[0021] In the present invention, an anti-electric shock circuit breaker is provided between the voltage regulator and the hollow cylindrical heating barrel, which can prevent special situations such as overload and short circuit.

[0022] In the present invention, the measurement system further comprises a camera and an infrared thermal imager;

[0023] The camera is facing the fire source simulation system and the water sprinkler system to record the entire fire extinguishing process;

[0024] The infrared thermal imager is directed toward the fuel sample on the fuel fixing bracket and can observe the temperature distribution on the surface of the fuel sample in real time; for example, it can record the temperature distribution on the surface of the fuel sample during the fire extinguishing process.

[0025] In the present invention, the fire source simulation system, water spray system and measurement system are arranged on a large platform;

[0026] The fuel fixing bracket is fixed on the platform, and a pulley track is provided on the platform along the horizontal rod direction of the fuel fixing bracket. The pulley under the hollow cylindrical heating barrel is set on the track and slides, so that the hollow cylindrical heating barrel can move back and forth along the track toward the horizontal rod of the fuel fixing bracket;

[0027] The nozzle bracket and the water tank are also fixed on the platform.

[0028] In the present invention, the water tank is provided with a capacity scale and a liquid level observation window, and the actual water consumption for fire extinguishing is measured by observing the capacity scale number corresponding to the liquid level.

[0029] In the present invention, four pulleys are installed at the bottom of the hollow cylindrical heating barrel, and the pulley tracks adopt parallel double tracks to achieve horizontal movement of 20 to 200 cm.

[0030] In the present invention, the voltage regulator is 2 The 5mm diameter copper wire is connected to the silicon carbon rod, and the heating power of the silicon carbon rod in the hollow cylindrical heating barrel can be adjusted within the voltage range of 0~380V; the maximum heating power in the hollow cylindrical heating barrel can reach 3000W.

[0031] In the present invention, the flow meter is connected to the nozzle through a water pipe and is used to measure the flow in the water pipe; the flow at the end of the water pipe is adjusted by switching the valve, and the flow at the end of the nozzle can be adjusted in the range of 0 to 2L / min in conjunction with the flow meter.

[0032] In the present invention, the water outlet and water intake ends of the water pump are respectively connected to the flow meter and the water tank through DN15 plastic water pipes. The water pump can operate at a power of 200w and 300w, and the water outlet flow rate can be in the range of 8~10L / min.

[0033] The principle of the present invention is:

[0034] The present invention can simulate the fire source state of smoldering wood in a forest fire scene and the fire extinguishing process of spraying smoldering wood with water through split combination and multiple adjustments; wherein,

[0035] The wood is used as a fuel sample, and a hole is punched in the center of the fuel sample to form a through-hole. The horizontal rod of the fuel fixing bracket passes through the hole to support the fuel sample, and then the hollow cylindrical heating barrel is pushed to the position of the horizontal rod by a pulley, so that the fuel sample passes through the opening at one end of the hollow cylindrical heating barrel and enters the center position of the hollow cylindrical heating barrel. The fuel sample is heated by energizing the silicon carbon rod to heat it; the voltage regulator is used to adjust the heating of the silicon carbon rod to adjust the hollow cylindrical heating barrel to different temperatures, and the heat flow data of the hollow cylindrical heating barrel is obtained by a heat flow data acquisition instrument. By controlling the heating power, the heat flow is calibrated to facilitate subsequent simulation of the smoldering state (under different heat flows, the wood will have different smoldering states); the real-time temperature of the hollow cylindrical heating barrel and the fuel sample is obtained by a temperature data acquisition instrument to facilitate subsequent observation of the fire extinguishing state;

[0036] The function of the quartz glass barrel is to stabilize the output radiation heat flow so that the silicon carbon rod heats the wood more evenly.

[0037] When the wood reaches the smoldering state required for the experiment, turn off the voltage regulator, cut off the power supply to stop heating, push the hollow cylindrical heating barrel away along the track, and expose the smoldering wood under the nozzle; according to the needs of the experiment, first adjust the nozzle height, then turn on the corresponding type of nozzle, start the water pump to drain the water in the water tank to spray the nozzle for fire extinguishing, adjust the spraying speed by adjusting the speed of the water pump, and measure the water supply intensity and water supply by the changes in the flow meter and water tank readings; in this way, the fire extinguishing characteristics of smoldering wood under different spray types, spray distances, and spray flow rates can be studied, which is relatively simple and comprehensive to consider the influencing factors in the wood smoldering fire extinguishing scenario.

[0038] The fire source simulation system independently designed by the present invention realizes consistent heating of the wood surface through a movable hollow cylindrical heating barrel and a fuel fixing bracket, and can effectively simulate different smoldering states of the fuel.

[0039] Through the integrated design, the present invention can realize multiple fire extinguishing scenarios with different spray types, spray flow rates and heights by only replacing the nozzle module and adjusting the flow meter and nozzle bracket height.

[0040] The advantages of the present invention are:

[0041] We independently designed a fire source simulation system that achieves consistent heating of the wood surface and can effectively simulate the different smoldering states of various fuels. Through an integrated piping and bracket design, we can simulate multiple firefighting scenarios with different spray types, spray rates, and heights simply by replacing the nozzle module and adjusting the flow meter and bracket height, obtaining more comprehensive smoldering firefighting data. This allows for multiple smoldering firefighting simulation experiments in different states, occupying a relatively small experimental space. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is an overall schematic diagram of the present invention.

[0043] Figure 2 This is a schematic diagram of the structure of the hollow cylindrical heating barrel of the present invention.

[0044] The numbers in the figure are: 1 is a hollow cylindrical heating barrel, 2 is a fuel fixing bracket, 3 is a pressure regulator, 4 is a pulley, 5 is a silicon carbon rod, 6 is an anti-electric shock circuit breaker, 7 is a quartz glass barrel, 8 is a nozzle, 9 is a flow meter, 10 is a switch valve, 11 is a water tank, 12 is a nozzle bracket, 13 is a water pump, 14 is a heat flow sensor, 15 is a heat flow data acquisition instrument, 16 is a temperature sensor, 17 is a temperature data acquisition instrument, 18 is a long operating tube, 19 is an experimental platform, and 20 is a support frame. DETAILED DESCRIPTION

[0045] The present invention includes a fire source simulation system, a water spray system, a measurement system and a metal plate as a basic experimental platform 19; and uses various types of wood as fuel samples.

[0046] The fire source simulation system includes a hollow cylindrical heating barrel 1, a fuel fixing bracket 2 and a pressure regulator 3.

[0047] The hollow cylindrical heating barrel 1 is cylindrical barrel-shaped and is formed by splicing two identical hollow semi-cylinders and fixing them with screws, which is convenient for disassembly and maintenance. Figure 2 As shown; the hollow cylindrical heating barrel 1 is made of metal as a whole, with circular openings at both ends; four pulleys 4 are provided at the bottom of the hollow cylindrical heating barrel 1, two in a group, and arranged symmetrically on the left and right.

[0048] The hollow cylindrical heating barrel 1 is provided with a plurality of silicon carbon rods 5 connected in series, and the silicon carbon rods are evenly arranged against the inner wall of the barrel, and asbestos for heat insulation is also provided between the silicon carbon rods and the inner wall of the barrel to prevent the surface of the hollow cylindrical heating barrel 1 from overheating during use, thereby reducing the risk of burns to the experimenters; the silicon carbon rods can be connected to the hollow cylindrical heating barrel 1 in a detachable snap-fit ​​manner through a C-shaped bayonet pre-welded on the inner wall of the barrel; the positive and negative poles of the silicon carbon rods 5 are connected in sequence to form a total positive and negative terminal; the hollow cylindrical heating barrel 1 has a preset wiring hole on the barrel body, and the total positive and negative terminals are connected to the voltage regulator 3 arranged outside the barrel through a connecting line through the wiring hole; the voltage regulator 3 is simultaneously connected to the power supply, and the voltage regulator 3 is connected through a 4m 2 A 5mm diameter copper wire is connected to the silicon carbon rod 5, which can adjust the heating power of the silicon carbon rod 5 within the voltage range of 0~380V, and the maximum heating power in the hollow cylindrical heating barrel 1 can be set to 3000W; an anti-electric shock circuit breaker 6 is also provided between the voltage regulator 3 and the hollow cylindrical heating barrel 1; it can prevent special situations such as overload and short circuit.

[0049] A cylindrical quartz glass barrel 7 is also provided in the hollow cylindrical heating barrel 1, which is coaxially arranged with the hollow cylindrical heating barrel 1. The quartz glass barrel 7 can be supported by welding a prefabricated support frame 20 in the hollow cylindrical heating barrel 1. The silicon carbon rod 5 is located between the inner wall of the hollow cylindrical heating barrel 1 and the outer wall of the quartz glass barrel 7; the function of the quartz glass barrel 7 is to stabilize the output radiant heat flow, so that the silicon carbon rod 5 heats the wood more evenly.

[0050] The fuel fixing bracket 2 has a vertical floor rod and a horizontal rod connected to it. The vertical floor rod is fixed to the experimental platform 19 by welding, and the horizontal rod is used to support the fuel sample; two parallel slide rails 8 are also fixedly welded on the experimental platform 19, and the two sets of pulleys 4 at the bottom of the hollow cylindrical heating barrel 1 correspond to a slide rail 8 respectively. The position of the slide rail 8 is to make the open end of the hollow cylindrical heating barrel 1 face the horizontal rod. The hollow cylindrical heating barrel 1 is moved by the pulley 4 to achieve a horizontal movement of 20~200cm, so that the horizontal rod (i.e., the fuel sample wood) can be moved in or out of the hollow cylindrical heating barrel 1.

[0051] Here, the method of fixing the fuel fixing bracket 2 and only moving the hollow cylindrical heating barrel 1 is to prevent the movement of the fuel sample from causing changes in measurement conditions and deviations in measurement results.

[0052] The water spray system includes a spray head 8, a flow meter 9, a switch valve 10 and a water tank 11 with a water pump 13;

[0053] The nozzle 8 can be replaced with three types of spray available on the market: direct current, fan-shaped spray, and cylindrical spray; for example, the rated working flow rate can be set to 0.56~1L / min; the nozzle 8 is detachably mounted above the fuel fixing bracket 2 via a nozzle bracket 12, and the nozzle bracket 12 is height-adjustable to adjust the distance between the horizontal rod (i.e., the fuel sample wood) and the nozzle; the nozzle bracket 12 and the water tank 11 are also fixed to the experimental platform 19; the height-adjustable structure of the nozzle bracket 12 can adopt a conventional telescopic rod structure available on the market, such as a conventional large and small sleeve nested telescopic structure, which will not be described in detail;

[0054] The nozzle 8 is connected to the water pump 13 of the water tank 11 via a water pipe; a flow meter 9 and a switch valve 10 are provided on the water pipe; the water pipe can be a full-length soft water pipe or a soft water pipe connected to a DN15 plastic water pipe, and the soft water pipe provides a movable margin for adjusting the height of the nozzle 8;

[0055] The water tank 11 is provided with a capacity scale and a liquid level observation window, so that the actual water consumption for fire extinguishing can be measured by observing the capacity scale number corresponding to the liquid level;

[0056] The flow meter 9 is connected to the nozzle 8 through a water pipe and is used to measure the flow in the water pipe; the flow at the end of the water pipe is adjusted by switching the valve 10, and the flow at the end of the nozzle can be adjusted in the range of 0 to 2L / min in conjunction with the flow meter;

[0057] The water outlet and water intake ends of the water pump 13 are connected to the flow meter 9 and the water tank 11 respectively through water pipes. For example, the water pump 13 can operate at a power of 200W and 300W, and the water outlet flow rate can be adjusted within the range of 8-10L / min.

[0058] The measurement system includes a heat flow sensor 14, a heat flow data acquisition device 15, a temperature sensor 16, a temperature data acquisition device 17, a camera and an infrared thermal imager;

[0059] The heat flux sensor 14 is provided at one end of an operating long tube 18. By holding the other end of the operating long tube 18, the heat flux sensor 14 is extended into the hollow cylindrical heating barrel 1. The connecting line between the heat flux sensor 14 and the heat flux data acquisition instrument 15 is passed through the operating long tube 18, and the line is well insulated. Before the formal experiment, the heat flux is pre-calibrated, and the instantaneous thermal radiation data of the hollow cylindrical heating barrel 1 is collected by connecting the heat flux data acquisition instrument 15. For example, with a heat flux of 15kw / m2 and heating for 12 minutes, the smoldering temperature of the wood can reach 500 degrees, which is also the most commonly used experimental benchmark. 500 degrees is also the stable temperature at which this type of wood reaches a stable smoldering spread state.

[0060] The temperature sensor 16 can be a long thermocouple, one end of which is fixed to the fuel sample. For example, a hole with a diameter of 1mm and a depth of 10mm is punched in the surface of the wood. The thermocouple is also 1mm in diameter and inserted into the hole to form a fixed position. There are several thermocouples, depending on the thickness of the wood, and they are arranged along the edge of the wood with a spacing of 10mm. (A metal clamp can also be used, or a fixing hole is pre-punched in the fuel sample and screwed onto the fuel sample via a threaded metal ring.) The other end is connected to the temperature data collector 17, which can collect temperature gradient change data inside the fuel sample.

[0061] Because a long thermocouple is used, the length of the thermocouple ensures that when most of one end of the thermocouple is located in the test area inside the hollow cylindrical heating barrel 1, the other end of the thermocouple is located outside the hollow cylindrical heating barrel 1, ensuring thermal insulation of the data line.

[0062] The heat flow data collector 15 and the temperature data collector 17 can be placed on a bracket pre-installed on the experimental platform 19 at a position convenient for operators to observe.

[0063] The camera is facing the fire source simulation system and the water sprinkler system, and is used to record the entire fire extinguishing process.

[0064] The infrared thermal imager is facing the fuel sample and can observe the temperature distribution on the surface of the fuel sample in real time; for example, it can record the temperature distribution on the surface of the fuel sample during the fire extinguishing process.

[0065] When the present invention is used, the specific operating steps are as follows:

[0066] (1) Select the fuel sample to be simulated, i.e. wood, and drill a transverse through-hole in the wood along its length. Align the transverse through-hole in the wood with the horizontal rod of the fuel fixing bracket, so that the horizontal rod passes through the through-hole. Fix the thermocouple on the wood.

[0067] (2) Set a calibration heat flux value in advance (the calibration heat flux value is determined by referring to the previous research literature [1], which studies the smoldering state of wood under different heat flux conditions, and points out the combustion state of wood under what heat flux conditions). First, use a long operating tube, fix the heat flux sensor on one end of the operating tube, and extend one end of the heat flux sensor from the opening at either end of the hollow cylindrical heating barrel to the center area. Start the voltage regulator, and the silicon carbon rod will start to heat up after being energized, evenly heating the heat flux sensor in the barrel until the heat flux data acquisition instrument shows that the calibration heat flux value has been reached. Record the voltage value of the voltage regulator; turn off the voltage regulator and take out the heat flux sensor.

[0068] (3) Push the hollow cylindrical heating barrel toward the horizontal rod of the fuel fixing bracket so that the fuel sample is located in the center area of ​​the hollow cylindrical heating barrel; start the voltage regulator and set the voltage to the voltage value recorded in step (2); the silicon carbon rod starts to heat up after being energized, and evenly heats the wood in the barrel. At the same time, observe the temperature data of the temperature sensor read by the temperature data acquisition instrument to make the wood reach the required smoldering state; turn off the voltage regulator; move the hollow cylindrical heating barrel away so that the wood simulating the smoldering effect is exposed to the nozzle;

[0069] (4) Install the nozzle with the spraying effect to be simulated on the nozzle bracket, connect the water pipe, adjust the height of the nozzle bracket, simulate the fire extinguishing distance, and record the current liquid level in the water tank through the page observation window on the water tank; start the camera and infrared thermal imager and start shooting; open the switch valve and start the water pump. The water pump simulates different water spraying speeds by adjusting different powers, and reads the flow data through the flow meter; the nozzle sprays the smoldering wood to extinguish the fire; when the temperature data acquisition instrument reads the temperature sensor data and reaches the specified temperature, it means that the fire is extinguished; close the switch valve and water pump, and record the current liquid level in the water tank, from which the amount of water consumed for fire extinguishing can be calculated; the infrared thermal imager and temperature sensor data (thermocouple) can also be used to assist in observing and judging whether the fire is extinguished. The temperature sensor is used to measure the temperature inside the wood, and the infrared thermal imager records the surface temperature; the camera records the entire heating and fire extinguishing process for subsequent review and research operations.

[0070] In summary, the present invention can study the fire extinguishing characteristics of smoldering wood under different spray types, spray distances, and spray flow rates, and can relatively simplify and comprehensively study the influencing factors of wood smoldering fire extinguishing scenarios. With these experimental data, fire extinguishing command and preparation can be carried out for certain specific forest fire scenes. For example, for smoldering fires of small-scale scattered fuels in forest fires, water consumption estimation based on combustion state estimation and preparation of efficient fire extinguishing water guns can be used to avoid insufficient or excessive water that wastes the physical strength of rescuers, so as to achieve the purpose of efficient fire extinguishing in the wild.

[0071] The fire source simulation system independently designed by the present invention realizes consistent heating of the wood surface through a movable hollow cylindrical heating barrel and a fuel fixing bracket, and can effectively change different smoldering states of the fuel.

[0072] The present invention uses an integrated pipeline and bracket design, so that multiple fire extinguishing scenarios with different spray types, injection flow rates and heights can be achieved by simply replacing the nozzle module and adjusting the flow meter and nozzle bracket height.

[0073] Although the above methods are illustrated and described as a series of structures for simplicity of explanation, it should be understood and appreciated that these methods are not specifically limited because according to one or more embodiments, some structures can occur in different orders and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0074] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0075] [1]Wang S, Ding P, Lin S, Gong J, Huang X. Smoldering and Flaming of Disc Wood Particles Under External Radiation: Autoignition and Size Effect. Front Mech Eng 2021;7.

Claims

1. A wood smoldering water spray fire extinguishing test device, characterized in that: Including fire source simulation system, water sprinkler system and measurement system; The fire source simulation system includes a hollow cylindrical heating barrel, a fuel fixing bracket and a pressure regulator; The hollow cylindrical heating barrel is cylindrical and has openings at both ends; A pulley is provided at the bottom of the hollow cylindrical heating barrel; The hollow cylindrical heating barrel is provided with a plurality of silicon carbon rods connected in series, and the silicon carbon rods are evenly arranged against the inner barrel wall; the positive and negative poles of the silicon carbon rods are connected in sequence to form a total positive and negative terminal; the total positive and negative terminals are connected to a voltage regulator disposed outside the barrel via connecting wires through pre-set wiring holes on the hollow cylindrical heating barrel body; the voltage regulator is also connected to a power supply; A cylindrical quartz glass barrel is also provided in the hollow cylindrical heating barrel, which is coaxially arranged with the hollow cylindrical heating barrel, and the silicon carbon rod is located between the inner wall of the hollow cylindrical heating barrel and the outer wall of the quartz glass barrel; The fuel fixing bracket is used to fix the fuel sample to be tested, and has a vertical floor rod and a horizontal rod connected thereto, and the horizontal rod is used to support the fuel sample; The open end of the hollow cylindrical heating barrel faces the horizontal rod, and the hollow cylindrical heating barrel is moved by the pulley so that the horizontal rod can move into or out of the hollow cylindrical heating barrel; The water spray system includes a spray head, a flow meter, a switch valve and a water tank with a water pump; The nozzle is arranged above the fuel fixing bracket through the nozzle bracket, the water spraying direction is toward the horizontal rod, and the nozzle is connected to the water pump of the water tank through a water pipe; the flow meter and the switch valve are arranged on the water pipe; The measurement system includes a heat flow sensor, a heat flow data acquisition instrument, a temperature sensor and a temperature data acquisition instrument; The heat flow sensor is connected to a heat flow data acquisition instrument. When the heat flow sensor is placed in the hollow cylindrical heating barrel, the heat flow data acquisition instrument collects instantaneous thermal radiation data of the hollow cylindrical heating barrel. The temperature sensor is connected to a temperature data collector. When the temperature sensor is placed on the fuel sample, the temperature gradient change data inside the fuel sample can be collected by the temperature data collector. Asbestos for heat insulation is also provided between the inner wall of the hollow cylindrical heating barrel and the silicon carbon rod; The nozzle is a direct current nozzle or a spray nozzle.

2. The wood smoldering water spray fire extinguishing test device according to claim 1, characterized in that: The nozzle support is height-adjustable, thereby adjusting the distance between the horizontal rod and the nozzle, that is, the distance between the fuel sample and the nozzle.

3. The wood smoldering water spray fire extinguishing test device according to claim 1, characterized in that: An anti-electric shock circuit breaker is also provided between the voltage regulator and the hollow cylindrical heating barrel.

4. The wood smoldering water spray fire extinguishing test device according to any one of claims 1 to 3, characterized in that: The measuring system also includes a camera and an infrared thermal imager; The camera is facing the fire source simulation system and the water sprinkler system to record the entire fire extinguishing process; The infrared thermal imager is directed toward the fuel sample on the fuel fixing bracket and can observe the temperature distribution on the surface of the fuel sample in real time.

5. The wood smoldering water spray fire extinguishing test device according to claim 4, characterized in that: The fire source simulation system, water sprinkler system and measurement system are arranged on a large platform; The fuel fixing bracket is fixed on the platform, and a pulley track is provided on the platform along the horizontal rod direction of the fuel fixing bracket. The pulley under the hollow cylindrical heating barrel is provided on the track and slides, so that the hollow cylindrical heating barrel can move back and forth along the track toward the horizontal rod of the fuel fixing bracket; The nozzle bracket and the water tank are also fixed on the platform.

6. The wood smoldering water spray fire extinguishing test device according to claim 5, characterized in that: The water tank is provided with a capacity scale and a liquid level observation window, and the actual water consumption for fire extinguishing is measured by observing the capacity scale number corresponding to the liquid level.

7. The wood smoldering water spray fire extinguishing test device according to claim 5, characterized in that: The water outlet and water intake ends of the water pump are connected to the flow meter and water tank respectively through DN15 plastic water pipes. The water pump operates at a power of 200w and 300w, and the water outlet flow rate is adjustable within the range of 8~10L / min.

8. An operating method of the wood smoldering water spray fire extinguishing test device according to claim 4, characterized in that: The specific steps are as follows: (1) Select the fuel sample to be simulated, i.e. wood, and drill a transverse through-hole in the wood along its length. Align the transverse through-hole in the wood with the horizontal rod of the fuel fixing bracket, so that the horizontal rod passes through the through-hole. Fix the thermocouple on the wood. (2) Set a calibration heat flow value in advance; First, use a long operating tube with a heat flux sensor fixed to one end of the operating tube. Insert one end of the heat flux sensor through the opening at either end of the hollow cylindrical heating barrel to the center area. Start the voltage regulator. The silicon carbon rod begins to heat up after being energized, evenly heating the heat flux sensor in the barrel until the heat flux data acquisition instrument displays the calibrated heat flux value. Record the voltage value of the voltage regulator. Then turn off the voltage regulator and remove the heat flux sensor. (3) Push the hollow cylindrical heating barrel toward the horizontal rod of the fuel fixing bracket so that the fuel sample is located in the center area of ​​the hollow cylindrical heating barrel; start the voltage regulator and set the voltage to the voltage value recorded in step (2); the silicon carbon rod starts to heat up after being energized, and evenly heats the wood in the barrel. At the same time, observe the temperature data of the temperature sensor read by the temperature data acquisition instrument to make the wood reach the required smoldering state; turn off the voltage regulator; move the hollow cylindrical heating barrel away so that the wood simulating the smoldering effect is exposed to the nozzle; (4) Install the sprinkler with the spray effect to be simulated on the sprinkler bracket, connect the water pipe, adjust the height of the sprinkler bracket, simulate the fire extinguishing distance, and record the current liquid level in the water tank through the page observation window on the water tank; start the camera and infrared thermal imager and start shooting; open the switch valve and start the water pump. The water pump simulates different water spraying speeds by adjusting different powers, and reads the flow data through the flow meter; the sprinkler sprays the smoldering wood to extinguish the fire; when the temperature data acquisition instrument reads the temperature sensor data and reaches the specified temperature, it means that the fire extinguishing state is achieved; close the switch valve and water pump, record the current liquid level in the water tank, and calculate the amount of water consumed for fire extinguishing; the infrared thermal imager can also be used to observe and determine whether the fire is extinguished. The temperature sensor is used to measure the temperature inside the wood, and the infrared thermal imager records the surface temperature; the camera records the entire heating and fire extinguishing process for subsequent review and research operations.

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