A warehouse special compressed air foam fire extinguishing device

Abstract

The application relates to the technical field of warehouse fire extinguishing, and particularly provides a compressed air foam fire extinguishing device special for warehouses, which comprises a body, the body is used for identifying fire and supplying pressure water, foam raw liquid and compressed air for fire extinguishing, further comprises a mixing nozzle, the mixing nozzle is internally provided with a mixing cavity and a Hartmann resonance structure, compressed air forms a standing wave at the Hartmann resonance structure, pressure water and foam raw liquid are mixed and then enter the standing wave area and form foam which is sprayed from a nozzle opening. The application adopts the Hartmann resonance structure to realize ultrasonic mixing of gas and liquid at the end of the nozzle, when a fire breaks out, foam is directly formed at the mixing nozzle without premixing, the long-distance foam conveying link in the main pipeline is omitted, the response speed is greatly improved, and the decay and pipe wall deposition and blockage problems of the premixed foam in the main pipeline due to static placement are avoided.

Description

Technical Field

[0001] This invention relates to the field of fire extinguishing technology for warehouses, and in particular to a compressed air foam fire extinguishing device specifically for warehouses. Background Technology

[0002] Compressed air foam fire extinguishing systems are a highly efficient fire suppression technology. By injecting compressed air into a foam mixture, a uniform and fine bubble structure is generated. Due to its excellent coverage, penetration, and insulation properties, it is widely used. Compressed air foam fire extinguishing systems generally adopt a "premixed" technical architecture. Its typical process flow is as follows: At the outlet of the water pump and air compressor, compressed air and a certain proportion of foam mixture are introduced into a static mixer or large premixing tank located near the pump station. Inside the mixer, through built-in baffles, porous media, or spiral channels, the gas and liquid phases undergo sufficient contact and mixing for a relatively long time under turbulent shearing action, pre-generating finished foam. Subsequently, the foamed finished foam is transported to the protected area via a main pipeline and finally released to the ignition point through terminal nozzles.

[0003] However, this method suffers from a delayed start-stop response. When a premixed system starts, the air in the main pipeline needs to be purged and filled with pre-mixed foam, a process that takes a considerable amount of time, resulting in a significant delay between the fire alarm and the actual foam dispensing from the terminal nozzles. In rapidly spreading warehouse fires, even a delay of a few seconds can cause the fire to escalate dramatically. Therefore, this application proposes a compressed air foam fire extinguishing device specifically for warehouses. Summary of the Invention

[0004] The purpose of this invention is to provide a compressed air foam fire extinguishing device specifically for warehouses, in order to solve the problem of slow response in current warehouse fire extinguishing devices.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A warehouse-specific compressed air foam fire extinguishing device includes a main body for identifying fires and supplying pressurized water, foam concentrate, and compressed air for fire extinguishing; and a mixing nozzle comprising: The nozzle housing is a hollow cavity structure. The nozzle housing is provided with a liquid inlet, which is connected to a mixing chamber located inside the nozzle housing. There are two liquid inlets, which are respectively connected to the structures on the main body that supply pressurized water and the structures that supply foam concentrate. A compressed air nozzle is fixedly connected to one end of the nozzle housing, and the nozzle outlet of the nozzle housing is located at the end away from the compressed air nozzle. The compressed air nozzle is in communication with the structure inside the body that supplies compressed gas. A resonant tube is located inside the nozzle housing. The resonant tube has a reflective hole that faces the compressed air nozzle at its outlet. The compressed air nozzle and the resonant tube form a Hartmann resonance structure. A gap is provided between the outer side of the resonant tube and the inner wall of the nozzle housing to form a foam flow channel. Pressurized water and foam concentrate are mixed in the mixing chamber and then enter one side of the gap between the compressed air nozzle and the resonant tube, and then sprayed out from the nozzle through the foam flow channel.

[0006] Furthermore, the compressed air nozzle has a Laval nozzle-shaped air passage at its center. The air passage has a straight section, a contraction section, a throat, and an expansion section arranged sequentially from the inlet end to the nozzle end. The straight section is a constant diameter section. The contraction section is connected to the front end of the straight section and is a tapered flow channel with a gradually narrowing cross section. The throat is connected to the front end of the contraction section and is the position with the smallest cross section in the entire flow channel. The expansion section is connected to the front end of the throat and is a tapered flow channel with a gradually expanding cross section.

[0007] Furthermore, the resonant tube is fixedly connected to the inside of the nozzle housing via a connecting seat, the connecting seat comprising: A connecting tube, wherein the connecting tube is a cylindrical structure with an opening at one end, and the resonant tube is located inside the connecting tube; A connecting block is located at the end of the connecting pipe away from the compressed air nozzle. The connecting block has an annular flange structure and a foam connecting hole that penetrates the connecting block.

[0008] Furthermore, the foam connecting holes are provided in multiple ways, and the multiple foam connecting holes are evenly distributed along the circumference.

[0009] Furthermore, the mixing nozzle also includes: An elastic element is provided, wherein the resonant tube and the connecting tube are in clearance fit, and the elastic element is located between the bottom of the resonant tube and the connecting tube.

[0010] Furthermore, the elastic element is a spring or a wave-shaped washer.

[0011] Furthermore, the mixing nozzle also includes: The mounting base has two connecting arms, one end of which is fixedly connected to the nozzle housing.

[0012] Furthermore, the mounting base is a pan-tilt structure, and the main body includes a fire sensor and a main control unit. The fire sensor integrates a visual positioning structure. After the fire sensor detects a fire source, the main control unit controls the pan-tilt to rotate, so that the mixing nozzle is aligned with the center of the fire source. After spatial locking is completed, the supply of gas, water and foam concentrate is started.

[0013] In summary, the present invention has the following advantages compared with the prior art: The compressed air foam fire extinguishing device for warehouses disclosed in this invention uses a Hartmann resonance structure to achieve gas-liquid ultrasonic mixing at the nozzle end. In the event of a fire, no premixing is required, and foam is formed directly at the mixing nozzle, eliminating the need for long-distance foam transportation in the main pipeline, thereby greatly improving the response speed. At the same time, it avoids the decay and pipe wall blockage problems caused by the premixed foam being left to stand in the main pipeline. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a warehouse-specific compressed air foam fire extinguishing device disclosed in an embodiment of the present invention.

[0015] Figure 2 This is a schematic diagram of the mixing nozzle in the warehouse-specific compressed air foam fire extinguishing device disclosed in an embodiment of the present invention.

[0016] Figure 3 This is an exploded view of the mixing nozzle in the warehouse-specific compressed air foam fire extinguishing device disclosed in an embodiment of the present invention.

[0017] Figure 4 This is a front view of the mixing nozzle in the warehouse-specific compressed air foam fire extinguishing device disclosed in an embodiment of the present invention.

[0018] Figure 5 for Figure 4 Sectional view of AA.

[0019] Figure 6 for Figure 2 The front view of the air nozzle in the mixed nozzle disclosed in the paper.

[0020] Figure 7 for Figure 2 A full cross-sectional view of the hybrid nozzle disclosed in the paper.

[0021] Figure 8 for Figure 2 A schematic diagram of the structure of the first housing in the hybrid nozzle disclosed in the paper.

[0022] Figure 9 for Figure 2 A full cross-sectional view of the first housing in the hybrid nozzle disclosed in the paper.

[0023] Figure 10 for Figure 2 A schematic diagram of the structure of the second housing in the disclosed hybrid nozzle.

[0024] Figure 11 for Figure 2 A full cross-sectional view of the second housing in the disclosed hybrid nozzle.

[0025] Figure 12 for Figure 2 A schematic diagram of the resonant tube in the hybrid nozzle disclosed in the paper.

[0026] Figure 13 for Figure 2 A full cross-sectional view of the resonant tube in the hybrid nozzle disclosed in the paper.

[0027] Figure 14 for Figure 2 A schematic diagram of the connecting seat in the hybrid nozzle disclosed in the paper.

[0028] Figure label: 101. Fire sensor; 102. Main control unit; 103. Water supply unit; 104. Foaming agent unit; 105. Gas supply unit; 106. Mixing nozzle; 200. Mounting base; 210. Connecting arm; 300. Nozzle housing; 310. First housing; 311. First connecting section; 312. First flow section; 313. Liquid inlet; 314. Connecting section; 315. Mixing section; 316. Second connecting section; 320. Second housing; 321. Gas nozzle connecting section; 322. First thread; 32 3. Second flow section; 324. Foaming section; 325. Liquid tank; 330. Third shell; 331. Foam outlet; 400. Compressed air nozzle; 401. Tightening head; 402. Air pipe connector; 403. Shell connection section; 410. Air passage; 411. Direct flow section; 412. Contraction section; 413. Throat; 414. Expansion section; 500. Resonance tube; 501. Reflection hole; 600. Connecting seat; 601. Connecting pipe; 602. Connecting block; 603. Foam connecting hole; 700. Elastic element. Detailed Implementation

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

[0030] Example 1: As Figure 1As shown, the warehouse-specific compressed air foam fire extinguishing device disclosed in this embodiment of the present invention includes a main body connected to a mixing nozzle 106. The main body includes a fire sensor 101, a main controller 102, a water supply unit 103, a foaming agent unit 104, and an air supply unit 105. The fire sensor 101 is used to detect fire signals and output them to the main controller 102. The main controller 102 is used to control the operation of the water supply unit 103, the foaming agent unit 104, and the air supply unit 105. The water supply unit 103 is used to input pressure into the mixing nozzle 106. The foaming agent unit 104 is used to input foam concentrate into the mixing nozzle 106. Pressurized water and foam concentrate are mixed in the mixing nozzle 106. The air supply unit 105 is used to input compressed air into the mixing nozzle 106. The mixing nozzle 106 is a Hartmann resonance ultrasonic nozzle with a built-in Hartmann resonance structure. The mixture formed by the pressurized water and foam concentrate flows to the Hartmann resonance structure. After the compressed air and water / foam concentrate are mixed in the mixing nozzle 106, a large amount of foam is generated and sprayed out from the mixing nozzle 106.

[0031] In this embodiment, the fire sensor 101 and the mixing nozzle 106 are installed in the same location, such as on the crossbeam between the shelves of an elevated warehouse, to ensure that the fire is detected nearby. The main control unit 102, the water supply unit 103, the foaming agent unit 104, and the air supply unit 105 are centrally installed in the equipment room or machine room on one side of the shelf. The water supply unit 103 and the foaming agent unit 104 are respectively connected to the mixing nozzle 106 through pipelines, and the air supply unit 105 is connected to the mixing nozzle 106 through pipelines. When the fire sensor 101 detects a fire signal and transmits it to the main control unit 102, the main control unit 102 first controls the air supply unit 105 to start, sending compressed air through the pipeline into the mixing nozzle 106. The compressed air generates Hartmann resonance in the mixing nozzle 106, exciting a self-excited oscillating ultrasonic field of a preset frequency. Subsequently, a stable standing wave is formed in the Hartmann resonance cavity of the mixing nozzle 106, forming an ultrasonic standing wave region. After the compressed air reaches stability, the main control unit 102 delays for 0.1 to 0.5 seconds to start the water supply unit 103 and the main control unit 105. In foaming agent unit 104, pressurized water and foam concentrate are mixed in proportion in the mixing nozzle 106 and injected into the ultrasonic standing wave zone. Under the action of ultrasonic cavitation effect, the mixture is instantly torn into micron-sized droplets, which are violently mixed with compressed air to generate foam with uniform bubble diameter. The generated foam is sprayed out from the nozzle of the mixing nozzle 106 and covers the fire source. After the fire is extinguished, the main control unit 102 first shuts down the water supply unit 103 and the foaming agent unit 104, and then shuts down the air supply unit 105 after a delay of 0.1 to 0.5 seconds, using the subsequent airflow to purge the residual liquid inside the nozzle.

[0032] The compressed air foam fire extinguishing device for warehouses disclosed in this invention uses a Hartmann resonance structure to achieve gas-liquid ultrasonic mixing at the nozzle end. In the event of a fire, no premixing is required, and foam is directly formed at the mixing nozzle 106, eliminating the need for long-distance foam transportation in the main pipeline, thereby greatly improving the response speed. At the same time, it avoids the decay and pipe wall blockage problems caused by the premixed foam being left to stand in the main pipeline.

[0033] Specifically, in this embodiment, the fire sensor 101 to the gas supply unit 105 are all existing technologies. For example, the fire sensor 101 can be a Honeywell infrared flame detector or a Siemens FDO221 smoke / heat composite fire detector; the main control unit 102 can be a Siemens or Honeywell fire alarm controller, and the fire sensor 101 and the main control unit 102 are electrically connected by wires; the water supply unit 103 can be a Wilo or Grundfos vertical multistage centrifugal pump; the foaming agent unit 104 can be a foam concentrate storage tank, with a control valve, which controls the opening of the channel between the storage tank and the mixing nozzle 106 when it is turned on; the gas supply unit 105 can be an Ingersoll Rand or Atlas Copco screw air compressor, with an air tank and a precision pressure regulating valve assembly.

[0034] As a preferred embodiment of this example, Figures 2 to 5 As shown, the mixing nozzle 106 includes a nozzle housing 300, a compressed air nozzle 400, and a resonant tube 500. The nozzle housing 300 is a hollow cavity structure. The compressed air nozzle 400 is fixedly connected to one end of the nozzle housing 300, and the nozzle outlet of the nozzle housing 300 is located at the end away from the compressed air nozzle 400. The resonant tube 500 is located inside the nozzle housing 300, and a reflective hole 501 is provided on the resonant tube 500. The reflective hole 501 is directly opposite the air outlet of the compressed air nozzle 400. The nozzle 400 and the resonant tube 500 constitute a Hartmann resonance structure. A gap is provided between the outer side of the resonant tube 500 and the inner wall of the nozzle housing 300. This gap is used to form a foam flow channel. The nozzle housing 300 is provided with a liquid inlet 313. The liquid inlet 313 communicates with the inside of the nozzle housing 300. There are two liquid inlets 313. The two liquid inlets 313 are respectively connected to the water supply unit 103 and the foaming agent unit 104. The compressed air nozzle 400 is connected to the air supply unit 105.

[0035] Specifically, in this embodiment, such as Figure 5 , Figures 8 to 11As shown, the nozzle housing 300 includes a first housing 310, a second housing 320, and a third housing 330. The first housing 310 is a cylindrical housing, and the third housing 330 is a housing structure with a conical hole inside. The second housing 320 and the third housing 330 are respectively fixedly connected to the two ends of the first housing 310. The compressed air nozzle 400 is fixedly connected to the second housing 320, and the resonant tube 500 is fixedly connected to the inside of the first housing 310.

[0036] like Figure 8 and Figure 9 As shown, the first housing 310 has a through-hole structure extending axially through the first housing 310. The through-hole structure inside the first housing 310 is sequentially provided with a first connecting section 311, a first flow section 312, a connecting section 314, and a second connecting section 316. The first connecting section 311, the first flow section 312, the connecting section 314, and the second connecting section 316 form a stepped hole structure. The first connecting section 311 is a threaded hole, while the first flow section 312 and the connecting section 314 are both smooth holes. A contraction-expansion mixing section 315 is provided between the first flow section 312 and the connecting section 314. The liquid inlet 313 is opened on the side wall of the first housing 310, and its internal opening is located at the first flow section 312.

[0037] like Figure 10 and Figure 11As shown, the exterior of the second housing 320 has a stepped structure, and the interior of the second housing 320 has a through-hole structure extending along its axis. The internal through-hole structure of the second housing 320 is a stepped hole structure. A first thread 322 and a second flow section 323 are sequentially arranged at the middle position of the external steps of the second housing 320. The outer diameter of the first thread 322 is larger than the outer diameter of the second flow section 323. A foaming section 324 is provided at the end of the second housing 320 located at the first housing 310. The foaming section 324 has a conical structure. The first thread 322 has an external thread and is connected to the first connecting section 311 via a threaded structure. A spiral liquid groove 325 is provided on the second flow section 323, extending from the end of the second flow section 323 to the foaming section 324. Section 323 is attached to the first flow section 312. When the first housing 310 is screwed onto the second housing 320, the opening of the liquid inlet 313 inside the second housing 320 is located at the end of the liquid tank 325 away from the foaming section 324. The foaming section 324 and the contraction part of the mixing section 315 cooperate and together form a mixing cavity. After the foam raw liquid enters from the liquid inlet 313, it is spirally guided to the mixing cavity through the liquid tank 325 and forms a mixed liquid in the mixing cavity. The mixed liquid enters the standing wave area from the expansion part of the mixing section 315. The second housing 320 is provided with a nozzle connecting section 321 at the position where it connects to the compressed air nozzle 400. The inner wall of the nozzle connecting section 321 is provided with an internal thread. The outside of the compressed air nozzle 400 is provided with a housing connecting section 403 that is adapted to the nozzle connecting section 321. The housing connecting section 403 is provided with an external thread.

[0038] The third housing 330 is a conical housing. The third housing 330 is connected to the end of the first housing 310 away from the second housing 320 by a threaded structure. Its conical inner cavity forms a tapered flow channel with the end of the stepped hole of the first housing 310.

[0039] like Figure 6 and Figure 7As shown, the compressed air nozzle 400 is a stepped tube. A Laval nozzle-shaped air passage 410 is centrally located on the compressed air nozzle 400. The air passage 410 is machined along the axis of the compressed air nozzle 400 and is used to deliver compressed air from the air pipe connector 402 to the nozzle end. From the inlet end to the nozzle end, the air passage 410 sequentially includes a direct flow section 411, a contraction section 412, a throat 413, and an expansion section 414. The direct flow section 411 is a constant diameter section used to stably supply compressed air into the compressed air nozzle 400. Airflow; the contraction section 412 is connected to the front end of the direct flow section 411 and is a tapered flow channel with a gradually narrowing cross section, used to accelerate the airflow; the throat 413 is connected to the front end of the contraction section 412 and is the position with the smallest cross section in the entire flow channel, with a diameter of 1.2 mm, used to make the airflow reach the speed of sound; the expansion section 414 is connected to the front end of the throat 413 and is a tapered flow channel with a gradually expanding cross section, with an outlet inner diameter of 1.8 mm, used to further accelerate the airflow to supersonic speed and eject it to form a high-speed jet.

[0040] The exterior of the air passage 410 is stepped, and an air pipe connector 402 is provided at its inlet end. The air pipe connector 402 extends axially from the rear end face of the tightening head 401 and is used to connect the compressed air supply pipeline from the air supply unit 105 to introduce high-pressure compressed air into the interior of the compressed air nozzle 400. A tightening head 401 is provided between the air pipe connector 402 and the housing connection section 403. The tightening head 401 is a hexagonal nut structure, which is convenient for tool clamping and fastening. The housing connection section 403 is located near the middle of the outer wall of the compressed air nozzle 400. It is an externally threaded section that is threaded with the first thread 322 to fix the compressed air nozzle 400 axially inside the second housing 320 and ensure the sealing of the installation. The part of the compressed air nozzle 400 located on the housing connection section 403 away from the air pipe connector 402 fits against the small-diameter section of the inner countersunk hole of the second housing 320.

[0041] The resonant tube 500 is a cylindrical tubular part with an outer diameter of 9.0 mm and a smooth outer wall. The rear end face of the resonant tube 500 is an annular plane perpendicular to the axis. The reflective hole 501 is located inside the front end face of the resonant tube 500. It is a blind hole with an inner diameter of 4.0 mm and a depth of 8.5 mm. The bottom of the hole is a hemispherical closed end. The reflective hole 501 is directly opposite the outlet of the expansion section 414 of the compressed air nozzle 400. It is used to receive the supersonic jet and generate an unstable shock wave at the mouth. The shock wave is reflected by the closed end in the hole and interacts with the subsequent jet, causing the air column to self-excite oscillate and generate an ultrasonic field.

[0042] The resonant tube 500 is fixedly connected to the inside of the nozzle housing 300 via a connecting seat 600. The connecting seat 600 includes a connecting tube 601, a connecting block 602, and a foam connecting hole 603. The connecting tube 601 is a cylindrical structure with an opening at one end. The resonant tube 500 is located inside the connecting tube 601. The connecting block 602 is located at the end of the connecting tube 601 away from the compressed air nozzle 400. The connecting block 602 is an annular flange structure with a foam connecting hole 603 penetrating through it. The foam connecting holes 603 are evenly distributed circumferentially around the axis of the connecting tube 601. The axis of the foam connecting holes 603 is parallel to that of the connecting tube 601. The axes of 1 are parallel, and multiple foam connecting holes 603 are provided. The multiple foam connecting holes 603 are evenly distributed along the circumference. In this embodiment, four foam connecting holes 603 are provided. The edges of the foam connecting holes 603 are located inside the second connecting section 316. The inner diameter of the second connecting section 316 is the same as the outer diameter of the foam connecting holes 603. When the third housing 330 is fixed to the first housing 310, the stepped structure on its inner side clamps the connecting block 602 inside the second connecting section 316. The resonant tube 500 and the connecting seat 600 are located inside the connecting section 314, and there is a gap between them and the inner wall of the connecting section 314 to form an annular channel for foam flow.

[0043] In this embodiment, the mixing nozzle 106 further includes a mounting base 200, such as... Figure 3 As shown, the mounting base 200 is a disc structure with two connecting arms 210. Each connecting arm 210 has a through-hole structure at its end away from the mounting base 200, connecting to the nozzle housing 300. The first housing 310 also has studs adapted to the through-hole structure on the connecting arm 210. The nozzle housing 300 is fixedly connected to the end of the connecting arm 210 away from the mounting base 200 by nuts. The mounting base 200 is used to fix the mixing nozzle 106 to a preset position. Example 2: As another embodiment of the present invention, this embodiment differs from Example 1 in that the mixing nozzle 106 further includes an elastic element 700. The resonant tube 500 and the connecting tube 601 are in clearance fit. The elastic element 700 is located between the bottom of the resonant tube 500 and the connecting tube 601. The elastic element 700 is a spring or a wave-shaped washer. When the compressed air nozzle 400 is not in operation, the elastic element 700 presses the resonant tube 500 tightly against the opening of the compressed air nozzle 400. When the compressed air nozzle 400 is in operation, the airflow backlash overcomes the elastic force of the elastic element 700, pushing the resonant tube 500 axially backward, thus forming a variable air gap between the reflector hole 501 and the expansion section 414. The outer diameter of the resonant tube 500 and the connecting tube 601 is smaller than the outer diameter of the small end of the bubbling section 324.

[0044] In this embodiment, the elastic element 700 can be configured to achieve two fire extinguishing modes. When compressed gas is not introduced into the compressed air nozzle 400, and only pressurized water is introduced into the mixing nozzle 106, since the outer diameter of the resonant tube 500 and the connecting pipe 601 is smaller than the outer diameter of the small end of the foaming section 324, most of the pressurized water flows between the resonant tube 500 and the inner wall of the nozzle housing 300. The pressurized water does not push the resonant tube 500, and it is difficult for the pressurized water to enter the inner cavity of the compressed air nozzle 400, preventing water from accidentally entering the gas path. At this time, the nozzle only sprays out water mist, realizing pure water-based fire extinguishing, which is used to extinguish ordinary fires, such as fires involving wood boards and cardboard boxes, reducing fire extinguishing costs. When water-based fire extinguishing is not possible or when it is necessary to enhance the fire extinguishing efficiency, compressed gas is introduced into the compressed air nozzle 400, and pressurized water and foam concentrate are introduced into the nozzle housing 300 at the same time. The airflow backlash pushes the resonant tube 500 backward, and a standing wave is formed between the resonant tube 500 and the compressed air nozzle 400, realizing foam fire extinguishing.

[0045] In this embodiment, the fire extinguishing mode is selected based on the raw material type of the storage location of the nozzle, and the raw material type is obtained from the warehouse management system.

[0046] Example 3: As another embodiment of the present invention, this embodiment differs from Example 2 in that the mounting base 200 adopts an electric pan-tilt unit, and the fire sensor 101 integrates a visual positioning structure.

[0047] In this embodiment, the mounting base 200 is a two-axis electric pan-tilt head in the prior art, with two degrees of freedom: horizontal rotation and vertical pitch. It is driven by a DC servo motor. The hybrid nozzle 106 is fixed to the rotating platform of the pan-tilt head via a connecting arm 210. The fire sensor 101 is an infrared thermal imaging and visible light binocular vision flame detector, integrated on the housing of the hybrid nozzle 106 or on the pan-tilt head. It can acquire infrared thermal images and visible light images of the fire source in real time, and calculate the azimuth and pitch coordinates of the fire source relative to the nozzle through image processing algorithms.

[0048] When the fire sensor 101 detects a fire source, the main control unit 102 first controls the pan-tilt unit to rotate rapidly, so that the foam outlet 331 of the mixing nozzle 106 is precisely aligned with the center of the fire source. After spatial locking is completed, the gas supply, water supply and foam concentrate supply are started according to the timing sequence described in Embodiment 1 or 2 to generate compressed air foam for targeted fire extinguishing. During the fire extinguishing process, the pan-tilt unit makes fine adjustments according to the changes in the fire intensity to ensure that the foam is always sprayed at the base of the flame.

[0049] This embodiment achieves automatic fire source tracking and precise pinpoint fire extinguishing through a gimbal and visual positioning structure, significantly improving the utilization rate of extinguishing agents and the speed of fire extinguishing. It is especially suitable for scenarios with dense shelves and definite fire source locations in high-bay warehouses.

[0050] In this embodiment, the fire source location method is an existing technology, such as the current binocular positioning technology, which combines infrared thermal imaging and visible light image fusion algorithms to achieve spatial location of the fire source.

[0051] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0052] It should be understood that although the present invention may use terms such as first, second, third, etc., to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of the present invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0053] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A warehouse-specific compressed air foam fire extinguishing device, comprising a body for identifying fires and supplying pressurized water, foam concentrate, and compressed air for fire extinguishing, and further comprising a mixing nozzle, characterized in that, The nozzle housing is a hollow cavity structure. The nozzle housing is provided with a liquid inlet, which is connected to a mixing chamber located inside the nozzle housing. There are two liquid inlets, which are respectively connected to the structures on the main body that supply pressurized water and the structures that supply foam concentrate. A compressed air nozzle is fixedly connected to one end of the nozzle housing, and the nozzle outlet of the nozzle housing is located at the end away from the compressed air nozzle. The compressed air nozzle is in communication with the structure inside the body that supplies compressed gas. A resonant tube is located inside the nozzle housing. The resonant tube has a reflective hole that faces the outlet of the compressed air nozzle. The compressed air nozzle and the resonant tube form a Hartmann resonance structure. A gap is provided between the outer side of the resonant tube and the inner wall of the nozzle housing to form a foam flow channel. Pressurized water and foam concentrate are mixed in the mixing chamber and then enter one side of the gap between the compressed air nozzle and the resonant tube, and then sprayed out from the nozzle through the foam flow channel.

2. The warehouse-specific compressed air foam fire extinguishing device according to claim 1, characterized in that, The compressed air nozzle has a Laval nozzle-shaped air passage at its center. The air passage has a straight section, a contraction section, a throat, and an expansion section arranged sequentially from the inlet end to the nozzle end. The straight section is a constant diameter section. The contraction section is connected to the front end of the straight section and is a tapered flow channel with a gradually narrowing cross section. The throat is connected to the front end of the contraction section and is the position with the smallest cross section in the entire flow channel. The expansion section is connected to the front end of the throat and is a tapered flow channel with a gradually expanding cross section.

3. The warehouse-specific compressed air foam fire extinguishing device according to claim 1, characterized in that, The resonant tube is fixedly connected to the inside of the nozzle housing via a connecting seat, the connecting seat comprising: A connecting tube, wherein the connecting tube is a cylindrical structure with an opening at one end, and the resonant tube is located inside the connecting tube; A connecting block is located at the end of the connecting pipe away from the compressed air nozzle. The connecting block has an annular flange structure and a foam connecting hole that penetrates the connecting block.

4. The warehouse-specific compressed air foam fire extinguishing device according to claim 3, characterized in that, The foam has multiple interconnecting holes, which are evenly distributed along the circumference.

5. The warehouse-specific compressed air foam fire extinguishing device according to claim 3, characterized in that, The mixing nozzle also includes: An elastic element is provided, wherein the resonant tube and the connecting tube are in clearance fit, and the elastic element is located between the bottom of the resonant tube and the connecting tube.

6. The warehouse-specific compressed air foam fire extinguishing device according to claim 5, characterized in that, The elastic element is a spring or a wave-shaped washer.

7. The warehouse-specific compressed air foam fire extinguishing device according to any one of claims 1-6, characterized in that, The mixing nozzle also includes: The mounting base has two connecting arms, one end of which is fixedly connected to the nozzle housing.

8. The warehouse-specific compressed air foam fire extinguishing device according to claim 7, characterized in that, The mounting base is a pan-tilt structure. The main body includes a fire sensor and a main control unit. The fire sensor integrates a visual positioning structure. After the fire sensor detects a fire source, the main control unit controls the pan-tilt to rotate, so that the mixing nozzle is aligned with the center of the fire source. After spatial locking is completed, the supply of gas, water and foam concentrate is started.

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