A new energy transport ship carbon dioxide fire extinguishing cooling system and a cooling method thereof

Abstract

The application relates to the technical field of ship design and construction, in particular to a new energy transport ship CO2 fire extinguishing and cooling system and a cooling method thereof. The system comprises a connecting pipeline, a first supply part, one end of which is connected with a CO2 supply device, the other end of which is communicated with the connecting pipeline, a second supply part, one end of which is connected with a fire water supply device, the other end of which is communicated with the connecting pipeline, and a terminal nozzle, one end of which is communicated with the connecting pipeline, the other end of which is communicated with a vehicle cabin. More effective temperature control means are introduced into the vehicle cabin fire extinguishing system, so that the temperature of a fire area is reduced, and the rekindling condition is inhibited, thereby improving the overall fire prevention and control capability of the new energy automobile.

Description

Technical Field

[0001] This application relates to the field of ship design and construction technology, and in particular to a carbon dioxide fire extinguishing and cooling system and cooling method for a new energy transport ship. Background Technology

[0002] Vehicle compartments are typically used for transport vehicles, and their internal environmental control and fire safety design are crucial to the overall vehicle operation safety. Traditional vehicle compartment ventilation systems usually only have a single air supply or exhaust function to meet daily ventilation needs. In terms of fire protection, the conventional strategy is to shut down all fans and vents in the event of a fire in the vehicle compartment, cutting off the air supply and fuel supply to prevent outside air from entering and to prevent oxygen from fueling combustion; simultaneously, a CO2 fire suppression system or a water sprinkler system is used for firefighting. These traditional technical solutions can play a certain role in dealing with fires caused by conventional fuels.

[0003] However, with the rapid development of the new energy vehicle industry, new energy vehicles, represented by lithium battery electric vehicles, hydrogen fuel cell vehicles, and natural gas vehicles, have been widely used. The power battery systems in these vehicles exhibit significant fire characteristics under thermal runaway conditions: First, the combustion temperature is extremely high; the external temperature of the power lithium battery can reach 283~1090℃, and the internal temperature can reach even higher, 572~1121℃, enough to quickly ignite other flammable materials inside the vehicle. Second, the fire spreads extremely rapidly; after localized thermal runaway of the lithium battery, it can rapidly expand within the battery module within seconds, igniting adjacent cells. Third, the fire reignites significantly; because the combustion reaction occurs inside the battery casing, conventional extinguishing agents are difficult to reach the root of the fire source for effective extinguishing, and secondary reignition is highly likely after the external open flames are extinguished, posing significant challenges to firefighting and rescue operations.

[0004] Existing fire suppression systems for new energy vehicles lack ideal fire suppression effects, and the risk of reignition is particularly prominent in high-temperature environments. Relying solely on traditional fire suppression methods cannot fundamentally solve the above-mentioned safety hazards. Summary of the Invention

[0005] Therefore, it is necessary to provide a carbon dioxide fire extinguishing cooling system and its cooling method for new energy transport ships that introduces a more effective temperature control method into the vehicle compartment fire extinguishing system to reduce the temperature of the fire area and suppress reignition conditions, thereby improving the overall fire prevention and control capabilities of new energy vehicles.

[0006] To solve the above-mentioned technical problems, this application provides the following technical solution: A carbon dioxide fire suppression and cooling system for new energy transport vessels, comprising: Connecting pipes; The first supply section is connected to the carbon dioxide supply equipment at one end and to the connecting pipeline at the other end. The second supply section is connected to the fire water supply equipment at one end and to the connecting pipeline at the other end; and, The end nozzle is connected to the connecting pipe at one end and to the vehicle compartment at the other end.

[0007] By adopting the above technical solution, the carbon dioxide supply equipment and the fire water supply equipment are connected to the first and second supply sections respectively, and the two share the connecting pipes and terminal nozzles. This allows the same set of pipe terminals to perform both CO2 fire extinguishing and seawater cooling functions after fire extinguishing. The structure is compact and the layout is reasonable, avoiding the space waste and cost increase caused by laying two complete sets of delivery pipes for the two media. It is especially suitable for space-constrained places such as ship and vehicle cabins. After the CO2 extinguishing agent is released, fire-fighting seawater is introduced through the second supply section and sprayed to cool the fire area through the same connecting pipes and terminal nozzles. This can quickly remove a large amount of heat from the battery pack and the surrounding environment, reducing the temperature below the safety threshold for lithium battery thermal runaway, suppressing the occurrence of reignition from the root, and significantly improving the safety and reliability of fire extinguishing.

[0008] In one embodiment, the second supply unit is connected to the connecting pipe via a detachable short pipe.

[0009] In one embodiment, the end nozzle includes an interconnected end branch pipe, a nozzle seat, and a nozzle, the end branch pipe being connected to the connecting pipeline, and the nozzle being mounted on the nozzle seat to spray the medium inside the end branch pipe.

[0010] In one embodiment, a switching valve is provided on the connecting pipeline, the switching valve being used to switch the connection between the first supply unit or the second supply unit and the connecting pipeline.

[0011] In one embodiment, the second supply unit is also connected to an external seawater supply device.

[0012] A cooling method, applied to the aforementioned carbon dioxide fire extinguishing cooling system of a new energy transport vessel, includes the following steps: S10: Sequentially open the main valve and the partition valve in the carbon dioxide release valve box, and connect the pipeline through the first supply section to start releasing carbon dioxide; S20: Close the main valve of the carbon dioxide main pipe, connect the connecting pipeline through the second supply section, turn on the fire pump, and the medium reaches the nozzle of the fire extinguishing area through the second supply section and the connecting pipeline to spray the medium to cool the fire area.

[0013] In one embodiment, prior to S10, preliminary preparations are performed, including: S11: Open the carbon dioxide release valve box in the engine compartment. At the same time the carbon dioxide release valve box is opened, the system will automatically send a pre-alarm signal, a light pole alarm signal, and a wind and oil cut-off reminder signal. S12: Confirm that all personnel in the fire area have been evacuated; S13: Close all exit doors, windows and passageways of the fire site, and shut down the corresponding fans and oil pumps; S14: Open the gas cylinder box, and open nitrogen cylinder No. 1 and nitrogen cylinder No. 2 in sequence.

[0014] In one embodiment, in S10, the system releases carbon dioxide after a delay of 20-40 seconds.

[0015] In one embodiment, in S20, a temperature sensor is installed inside the vehicle compartment, and the fire pump is shut down when the temperature drops to the lower limit of thermal runaway.

[0016] Compared with existing technologies, a new energy transport ship carbon dioxide fire extinguishing and cooling system connects the carbon dioxide supply equipment and the fire water supply equipment through a first supply section and a second supply section, respectively. The two share the connecting pipes and terminal nozzles, allowing the same set of pipe terminals to perform both CO2 fire extinguishing and seawater cooling functions after fire extinguishing. The system has a compact structure and reasonable layout, avoiding the space waste and cost increase caused by laying two complete sets of delivery pipes for the two media. It is especially suitable for space-constrained places such as ship vehicle compartments. After the CO2 extinguishing agent is released, fire-fighting seawater is introduced through the second supply section and sprayed to cool the fire area through the same connecting pipes and terminal nozzles. This can quickly remove a large amount of heat from the battery pack and the surrounding environment, reducing the temperature below the safety threshold for lithium battery thermal runaway, suppressing the occurrence of reignition from the root, and significantly improving the safety and reliability of fire extinguishing. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of a carbon dioxide fire extinguishing and cooling system for a new energy transport vessel, provided in this application.

[0019] Figure 2 This application provides a schematic diagram of the structure of the terminal nozzle of a carbon dioxide fire extinguishing and cooling system for a new energy transport vessel.

[0020] The component labels are as follows: 1. Connecting pipe; 2. First supply section; 3. Second supply section; 4. Terminal nozzle; 41. Terminal branch pipe; 42. Nozzle seat; 43. Nozzle. Detailed Implementation

[0021] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0022] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0024] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0026] Vehicle compartments are typically used for transport vehicles, and their internal environmental control and fire safety design are crucial to the overall vehicle operation safety. Traditional vehicle compartment ventilation systems usually only have a single air supply or exhaust function to meet daily ventilation needs. In terms of fire protection, the conventional strategy is to shut down all fans and vents in the event of a fire in the vehicle compartment, cutting off the air supply and fuel supply to prevent outside air from entering and to prevent oxygen from fueling combustion; simultaneously, a CO2 fire suppression system or a water sprinkler system is used for firefighting. These traditional technical solutions can play a certain role in dealing with fires caused by conventional fuels.

[0027] However, with the rapid development of the new energy vehicle industry, new energy vehicles, represented by lithium battery electric vehicles, hydrogen fuel cell vehicles, and natural gas vehicles, have been widely used. The power battery systems in these vehicles exhibit significant fire characteristics under thermal runaway conditions: First, the combustion temperature is extremely high; the external temperature of the power lithium battery can reach 283~1090℃, and the internal temperature can reach even higher, 572~1121℃, enough to quickly ignite other flammable materials inside the vehicle. Second, the fire spreads extremely rapidly; after localized thermal runaway of the lithium battery, it can rapidly expand within the battery module within seconds, igniting adjacent cells. Third, the fire reignites significantly; because the combustion reaction occurs inside the battery casing, conventional extinguishing agents are difficult to reach the root of the fire source for effective extinguishing, and secondary reignition is highly likely after the external open flames are extinguished, posing significant challenges to firefighting and rescue operations.

[0028] Existing fire suppression systems for new energy vehicles lack ideal fire suppression effects, and the risk of reignition is particularly prominent in high-temperature environments. Relying solely on traditional fire suppression methods cannot fundamentally solve the above-mentioned safety hazards.

[0029] Therefore, it is necessary to provide a carbon dioxide fire extinguishing and cooling system for new energy transport ships that introduces a more effective temperature control method into the vehicle compartment fire extinguishing system to reduce the temperature of the fire area, suppress reignition conditions, and thus improve the overall fire prevention and control capabilities of new energy vehicles.

[0030] Please see Figures 1 to 2 This application provides a carbon dioxide fire extinguishing and cooling system for a new energy transport vessel, comprising a connecting pipe 1, a first supply unit 2, a second supply unit 3, and a terminal nozzle 4. The connecting pipe 1 is used to transport the fire extinguishing or cooling medium from the supply end to the protected area of ​​the vehicle compartment.

[0031] The material for connecting pipe 1 can be seamless steel pipe No. 20 or galvanized steel pipe resistant to seawater corrosion. For pipes with a nominal diameter equal to or less than 80 mm, threaded connections are preferred for easy on-site installation, disassembly, and maintenance; for pipes with a nominal diameter greater than 80 mm, flange connections are preferred to ensure sealing and structural strength. Connecting pipe 1 is arranged along the ship's deck or bulkheads, and further, it can run along air ducts or other existing piping systems for protection. Connecting pipe 1 exposed in the cargo hold area is equipped with a protective cover or other protective measures to prevent mechanical damage.

[0032] The laying path of connecting pipeline 1 avoids areas frequently used by crew members, such as living quarters, service areas, and control stations, to ensure that pipeline leaks or accidental discharges will not pose a threat to personnel safety. Additionally, connecting pipeline 1 is equipped with a check valve to prevent backflow of extinguishing agent or cooling water, a pressure gauge for daily monitoring of the system's operating pressure, and a flushing connection for regular cleaning and maintenance. To ensure the effective spraying of CO2 extinguishing agent, tee fittings are preferentially used in connecting pipeline 1 to maintain a balance of extinguishing agent flow and pressure across all branches.

[0033] One end of the first supply unit 2 is connected to the carbon dioxide supply equipment, and the other end is connected to the aforementioned connecting pipeline 1. This supply unit is the inlet control unit of the entire CO2 fire extinguishing system, and is mainly responsible for safely and quickly releasing the high-pressure liquid CO2 stored in the gas cylinder group into the connecting pipeline 1.

[0034] Carbon dioxide supply equipment is typically housed in a dedicated CO2 cylinder room on board. The cylinders are high-pressure seamless steel cylinders, and multiple cylinders are connected in parallel via high-pressure hoses or manifolds to form a cylinder group, meeting the total dosage requirements for a single fire suppression operation. The first supply unit 2, as a piping integration module, internally includes at least a container valve, a selector valve, and a main release valve. The container valve is installed at the neck of each cylinder and remains sealed to prevent CO2 leakage when not in operation. The selector valve is used on ships equipped with multiple vehicle compartments or protected zones to release CO2 to designated fire areas as needed. The main release valve is the master control switch for system activation.

[0035] During operation, first confirm that all personnel in the fire area have evacuated and that all doors, windows, ventilation openings, and passageways in the fire area are closed. Then, open the gas cylinder box and sequentially open the corresponding nitrogen drive cylinders, which are filled with high-pressure nitrogen as a power source. Next, sequentially open the main valve and the corresponding zone valve in the first supply unit 2. To prevent accidental CO2 release into non-fire areas, each ball valve and operating handle is equipped with a clear nameplate and operation markings. In addition, the first supply unit 2 is equipped with a delay device to ensure that the system automatically issues a pre-alarm signal, including an audible and visual alarm and a ventilation and oil cut-off signal, within a delay of approximately 20 to 40 seconds after the release valve is opened, so that personnel have sufficient time to evacuate the protected area. After completing the above operations, the high-pressure liquid CO2 enters the connecting pipeline 1 through the first supply unit 2 and is delivered to the vehicle compartment for total flooding fire suppression.

[0036] One end of the second supply unit 3 is connected to the fire water supply equipment, and the other end is connected to the aforementioned connecting pipe 1. It is used to introduce fire seawater into the main CO2 pipeline after the CO2 system has finished releasing water to achieve efficient cooling of the fire area.

[0037] In marine engineering, ships are equipped with independent fire-fighting water systems, which consist of fire pumps, fire-fighting pipelines, and outdoor fire hydrants. Specifically, the second supply section 3 is a bypass branch pipe connected to the main CO2 pipe. The diameter of this branch pipe can be the same as or slightly smaller than that of the main CO2 pipe to ensure adequate cooling water supply. Normally, the port of this branch pipe is sealed with a flange blind plate to prevent leakage of CO2 extinguishing agent during release and to prevent foreign objects from entering the pipeline and causing blockages. During normal navigation, the flange blind plate should be locked and sealed with a lead seal.

[0038] After the CO2 system completes a one-time release of extinguishing agent, if the temperature inside the vehicle compartment is still high or there is a risk of lithium battery reignition, the operator shall perform a cooling operation: First, close the main valve on the CO2 main pipe to prevent cooling water from flowing back into the CO2 cylinder group; second, remove the flange blind plate at the branch pipe port of the second supply section 3; then, connect the branch pipe port of the second supply section 3 to the fire hydrant or fire water pipeline outlet of the ship's fire water system through a detachable short pipe.

[0039] Both ends of the detachable short pipe have standard flange interfaces or fire-fighting connectors, allowing for quick connection in emergencies. After connection, the fire pump is started, and seawater or fire-fighting water from outside the ship, under the pressure of the fire pump, enters the main CO2 pipeline through the fire-fighting water pipeline and the branch pipe of the second supply section 3, and is finally sprayed to the fire area in the vehicle compartment through the terminal nozzles 4. The setting of the second supply section 3 allows the system to achieve pipeline sharing and functional integration with almost no change to the main structure of the original CO2 fire extinguishing system and the main structure of the fire-fighting water system, simply by adding branch pipes and detachable short pipes. The equipment modification cost is low, the construction period is short, and it has good engineering applicability. To prevent seawater from accumulating in the pipeline and causing corrosion, the connecting pipeline 1 can be flushed with compressed air or fresh water after the cooling operation is completed.

[0040] One end of the terminal nozzle 4 is connected to the connecting pipe 1, and the other end is connected to the interior space of the vehicle compartment. This nozzle serves as the interface terminal between the system and the vehicle compartment environment, and is responsible for spraying CO2 extinguishing agent or cooling water in a suitable form to the protected area.

[0041] The terminal nozzle 4 is designed to accommodate both gas extinguishing and liquid cooling modes. In CO2 extinguishing mode, the terminal nozzle 4 is an open nozzle without heat-sensitive elements. Its internal channel design ensures that CO2 gas rapidly diffuses throughout the vehicle compartment within a short time, reaching the required extinguishing concentration. In specific embodiments, the nozzle orifice diameter and number of the terminal nozzle 43 need to be hydraulically calculated based on the volume of the protected area and the CO2 supply intensity.

[0042] In cooling mode, when switching to fire water supply, the terminal nozzle 4 acts as the spray terminal for cooling water mist. To achieve better cooling effect, the terminal nozzle 4 can be designed as a fine water mist nozzle 43. Specifically, the nozzle 43 has a spiral inner flow channel. When the cooling water passes through this spiral flow channel under high pressure, it rotates at high speed and forms a water mist with a certain atomization angle and droplet size distribution after leaving the nozzle 43. The fine water mist has a very large specific surface area, which can quickly absorb the heat in the fire smoke and vaporize it. A large amount of heat energy is dissipated through the phase change heat transfer, thereby rapidly reducing the ambient temperature inside the vehicle compartment and the surface temperature of the burning object. According to thermodynamic principles, the latent heat of vaporization of water is approximately 2257 kJ / kg, so water mist cooling has extremely high thermal efficiency. The arrangement and spacing of the terminal nozzles 4 inside the vehicle compartment must ensure that the water mist can cover the entire protected area, especially with a denser arrangement in the heat accumulation areas at the top of the vehicle compartment and near the battery pack.

[0043] Meanwhile, a network of temperature sensors is installed inside the vehicle compartment to monitor the temperature data of each zone in real time. Once operators receive feedback from the temperature sensors indicating that the temperature in a given area has dropped below the safe threshold for lithium battery thermal runaway, they can manually shut off the fire pump to stop water spraying. Considering that lithium battery fires may experience temperature rebound due to internal chemical reactions, the system can intermittently or continuously spray water for cooling based on temperature monitoring data until the temperature stabilizes within a safe range. This effectively prevents the fire from reigniting and maximizes the safety of the transport vehicle and the ship itself.

[0044] The terminal nozzle 4 includes an interconnected terminal branch pipe 41, a nozzle seat 42, and a nozzle 43. The terminal branch pipe 41 serves as a transitional connecting section between the connecting pipeline 1 and the terminal spray structure. One end of the branch pipe is connected to the connecting pipeline 1, and the other end is fixedly connected to the nozzle seat 42. The terminal branch pipe 41 is made of seamless steel pipe of the same material as the main pipe of the connecting pipeline 1. Its nominal diameter can be reasonably selected according to the required flow rate of extinguishing agent and cooling water in the protected area of ​​the vehicle compartment. However, under normal circumstances, the diameter of the terminal branch pipe 41 is not greater than the diameter of the main pipe of the connecting pipeline 1 to ensure that the medium can maintain sufficient spray pressure before entering the nozzle 43.

[0045] The terminal branch pipe 41 can be connected to the connecting pipe 1 by welding or threaded flange. Welding has the advantages of robust structure and low leakage risk, and is especially suitable for permanent pipe connections in the vibration environment of ships. Flange connection facilitates subsequent maintenance and replacement. To prevent pipe damage caused by seawater corrosion or high temperature during long-term use, the outer wall of the terminal branch pipe 41 is coated with a high-temperature resistant and corrosion-resistant coating, and it is firmly fixed to the top structure or bulkhead of the vehicle compartment by pipe clamps or brackets along its length to resist the swaying and vibration impact during ship navigation.

[0046] The nozzle seat 42 serves as a hollow transitional connection base, reliably assembling the end branch pipe 41 and the nozzle 43 into an integrated spray unit. One end of the nozzle seat 42 has a connection interface adapted to the port of the end branch pipe 41. This connection interface can be configured as a socket weld joint or an internal threaded joint according to actual process requirements. When a socket weld connection is used, the end of the end branch pipe 41 is inserted into the socket hole of the nozzle seat 42 and sealed and fixed through a circumferential fillet weld, resulting in high connection strength suitable for high-pressure conditions. When a threaded connection is used, the internal thread of the nozzle seat 42 engages with the external thread of the end branch pipe 41, and PTFE sealing tape or thread sealant is wrapped between the threaded mating surfaces to achieve effective sealing under high-pressure media conditions. The other end of the nozzle seat 42 has a mounting chamber for installing the nozzle 43. This mounting chamber is typically configured with an internally threaded hole, the thread specification of which matches the external thread of the nozzle 43 base. To ensure the sealing performance of the nozzle 43 after installation, an annular sealing groove is provided at the contact end face between the nozzle seat 42 and the nozzle 43. An O-ring or a spiral wound gasket is embedded in this sealing groove. When the nozzle 43 and nozzle seat 42 are tightened by the threads, the O-ring is compressed and undergoes elastic deformation, thereby blocking the path of media leakage outward along the thread gap.

[0047] The nozzle holder 42 can be designed as a hexagonal prism or a cylindrical structure with relatively parallel wrench faces, facilitating the disassembly and assembly of the nozzle holder 42 by operators using adjustable wrenches or special socket tools. The nozzle holder 42 is preferably made of 316L austenitic stainless steel or high-strength copper alloy forgings, which offer excellent resistance to seawater corrosion. These materials not only possess good mechanical strength and machinability but also effectively resist pitting corrosion and stress corrosion cracking caused by chloride ions after prolonged contact with seawater cooling media, thus ensuring the reliability of the nozzle holder 42 throughout the ship's entire lifespan.

[0048] The nozzle 43, installed within the mounting chamber of the nozzle seat 42, is the terminal element that determines the final spray pattern and coverage area of ​​the medium. The nozzle 43 has an axially extending through-cavity inside its main body. The front port of this through-cavity is sequentially connected to the mounting chamber of the nozzle seat 42 and the internal flow channel of the end branch pipe 41, allowing the high-pressure medium from the connecting pipe 1 to smoothly enter the nozzle 43. A specific diameter and number of nozzle orifices are formed on the spray end face of the nozzle 43. The nominal diameter and number of orifices need to be precisely calculated based on factors such as the vehicle compartment volume, the required fire extinguishing concentration, or the density of the cooling water mist.

[0049] As a preferred embodiment, the nozzle 43 has a swirling guide structure within its through-cavity. This swirling guide structure can be specifically configured as a spiral guide groove or a swirling core with tangential oblique holes. When the high-pressure liquid medium flows through this spiral guide structure, the medium acquires a strong tangential velocity and generates high-speed centrifugal rotation. At the moment of exiting the nozzle, the liquid film breaks into fine and uniformly distributed droplets under the combined action of centrifugal force and aerodynamic force. The droplet diameter of the fine water mist can typically be controlled between 100μm and 400μm. Water mist with this particle size has a very large specific surface area, enabling it to quickly absorb heat from a fire and vaporize. Through the latent heat of phase change, it efficiently removes heat energy, achieving rapid physical cooling of the high-temperature environment inside the vehicle compartment and the thermal runaway area of ​​the lithium battery.

[0050] Meanwhile, when the system operates in CO2 fire suppression mode, the nozzle 43's orifice area and flow channel design ensure that high-pressure CO2 gas can rapidly diffuse throughout the entire vehicle compartment, achieving the total flooding fire suppression effect required by regulations. The nozzle 43 can be made of a wear-resistant copper-based alloy or precision stainless steel, and the machining accuracy of its orifices must be controlled within a high tolerance range to ensure good consistency in the spray flow rate and atomization angle of each batch of nozzles 43.

[0051] Through the sequential connection and cooperation of the aforementioned end branch pipe 41, nozzle seat 42 and nozzle 43, this system can be compatible with CO2 extinguishing medium and fire water cooling medium on the same end spray terminal. This not only meets the need for rapid extinguishing of initial fires in the vehicle compartment, but also allows for continuous water spraying and cooling after the fire is extinguished to prevent the lithium battery from thermally running away and reigniting, thereby significantly improving the overall fire safety level of the vehicle compartment of new energy transport ships.

[0052] A switching valve is installed on the connecting pipeline 1, which is used to switch the connection between the first supply unit 2 or the second supply unit 3 and the connecting pipeline 1. In one embodiment, the switching valve adopts a valve group structure adapted to the system pipeline layout, including a main shut-off valve installed on the main pipe of the connecting pipeline 1 and a branch switching valve installed on the branch pipe connected to the second supply unit 3. The inlet end of the main shut-off valve is connected to the output end of the first supply unit 2, and its outlet end is connected to the downstream pipe section of the connecting pipeline 1 near the end nozzle 4; the branch switching valve is installed on a branch pipe leading out from the CO2 main pipe, one end of which is connected to the connecting pipeline 1 between the main shut-off valve and the end nozzle 4, and the other end forms the connection port of the second supply unit 3.

[0053] When the system operates in CO2 extinguishing mode, the switching valve is set to the first operating state: the main shut-off valve is in the fully open position, allowing the high-pressure CO2 extinguishing agent output from the first supply unit 2 to flow through the main shut-off valve and enter the downstream of the connecting pipeline 1; simultaneously, the branch switching valve is in the fully closed position, and its port is sealed by a flange blind plate, thereby cutting off the passage between the second supply unit 3 and the connecting pipeline 1. The high-pressure CO2 extinguishing agent can only enter the connecting pipeline 1 through the first supply unit 2 and the open main shut-off valve, and is finally released from the terminal nozzle 4 into the vehicle compartment, ensuring that the extinguishing agent concentration and spray pressure are not affected by diversion.

[0054] When the CO2 system completes the release of the extinguishing agent and needs to activate the cooling mode, the operator must first completely close the main shut-off valve to cut off the connection between the first supply unit 2 and the connecting pipeline 1. This prevents the subsequent introduction of fire-fighting seawater from flowing back into the CO2 cylinder group or nitrogen-driven pipeline, causing equipment damage or safety hazards. Then, remove the flange blind plate at the branch switching valve port and quickly connect the outlet of the ship's fire-fighting water system to the inlet of the branch switching valve using a detachable short pipe. Next, open the branch switching valve. At this point, the switching valve is switched to the second operating state: fire-fighting seawater flows through the second supply unit 3, the branch switching valve, and the branch pipe into the main pipeline of connecting pipeline 1, and is then delivered to the terminal nozzles 4 for spraying and cooling.

[0055] Through the linkage switching of the main shut-off valve and the branch switching valve, the system can conveniently select to connect the first supply section 2 or the second supply section 3 according to different stages of the fire extinguishing operation, while sharing a set of terminal connection pipeline 1 and terminal nozzle 4. There is no need to lay two complete sets of terminal delivery pipelines for the two media, thereby effectively reducing the space occupied by pipelines on the top and sides of the vehicle compartment, reducing the consumption of pipe materials and the difficulty of construction.

[0056] This application also provides a cooling method applied to the aforementioned carbon dioxide fire suppression cooling system of new energy transport vessels. In the event of a fire in the vehicle compartment of a new energy transport vessel, the cooling method first utilizes a CO2 fire suppression system for rapid total flooding extinguishing, and then, after the CO2 has been released, uses seawater for continuous physical cooling of the vehicle compartment, thereby effectively suppressing the risk of reignition of lithium batteries due to high temperatures.

[0057] When a fire is confirmed to have occurred in the vehicle compartment and portable fire extinguishers are no longer effective in extinguishing the fire, the operator shall perform the following preliminary preparations in accordance with the emergency response procedure.

[0058] First, perform step S11: Open the CO2 release valve box in the engine compartment. This release valve box is usually located in an easily accessible, secure area outside the vehicle compartment. The front of the box has a transparent tempered glass observation window and a sealed key box. The operator must first break the glass cover of the key box, remove the release box key, and use the key to unlock the CO2 release valve box door.

[0059] When the release valve box door is opened, the limit switch inside the system is triggered. This limit switch is electrically connected to the ship's fire alarm control cabinet, which then automatically issues a pre-alarm signal. Specifically, the audible and visual alarms in the vehicle compartment and adjacent areas will emit a continuous buzzing sound and flashing red lights to warn all personnel that a CO2 extinguishing agent is about to be released from the fire. At the same time, the alarm signal lights located at the entrances to the bridge, engine room control room, and vehicle compartment will illuminate, conveying a clear emergency status message to all personnel on board. In addition, the system automatically issues a ventilation and fuel cut-off reminder signal. This reminder signal is broadcast as a "ventilation and fuel cut-off" voice prompt through the ship's public address system and also transmitted as an electrical signal to the ventilation fan control cabinet and fuel pump control cabinet in the engine room, preparing for the subsequent ventilation and fuel cut-off operation.

[0060] Next, proceed to step S12: Confirm that all personnel in the fire area have evacuated. Because the release of CO2 extinguishing agent will rapidly create a high-concentration CO2 atmosphere within the protected area, operators must verify, through multiple methods including the infrared thermal imaging monitoring system installed inside the vehicle compartment, the entry / exit registration sign at the door, and visual inspection, that no personnel remain inside the vehicle compartment. After confirming that all personnel have safely evacuated, operators should close and lock all watertight doors, fire doors, and personnel access entrances / exits in the vehicle compartment to ensure that no one can accidentally re-enter.

[0061] Then, execute step S13: Close all exit doors, windows, and passageways in the fire area, and shut down the corresponding fans and oil pumps. Specifically, the operator remotely shuts down the vehicle compartment's supply and exhaust fans and their corresponding fire dampers by pressing the "air and oil cut-off" button on the engine room control console or fire control station, ensuring that the ventilation channels between the vehicle compartment and the outside atmosphere are completely blocked. At the same time, cut off the power supply to all fuel pumps and lubricating oil pumps in the vehicle compartment area to eliminate the risk of fire spread that may be caused by continuous fuel supply. By closing doors, windows, passageways, and ventilation systems, the vehicle compartment is made into a sealed protective space, creating the necessary conditions for maintaining a sufficient extinguishing concentration of CO2 extinguishing agent, while preventing fresh air from entering the vehicle compartment and preventing oxygen from continuously fueling combustion.

[0062] Finally, proceed to step S14: Open the cylinder box, and then open nitrogen cylinders No. 1 and No. 2 in sequence. Carbon dioxide cylinder groups are typically housed in a dedicated CO2 cylinder room on board. Each cylinder group is equipped with one or more nitrogen drive cylinders filled with high-pressure nitrogen, serving as the power source for opening the CO2 cylinder valves. The operator first opens the valve of nitrogen cylinder No. 1. The high-pressure nitrogen enters the manifold through the drive line, actuating the pilot valve of the CO2 cylinder group. Then, nitrogen cylinder No. 2 is opened to provide backup or supplementary driving force, ensuring that all CO2 cylinder valves can be reliably opened.

[0063] After completing the above preliminary preparations, proceed to step S10: sequentially open the main valve and zone valves in the CO2 release valve box, and connect to pipeline 1 through the first supply unit 2 to begin releasing CO2. Following the clearly marked operating sequence on the valve control panel inside the release valve box, the operator first opens the CO2 release main valve, connecting the main output pipe of the CO2 cylinder group to the main pipe of pipeline 1; then, based on the fire location, opens the corresponding zone valve to direct the CO2 extinguishing agent to the specific vehicle compartment protection area.

[0064] To prevent misoperation, each ball valve in the release valve box is equipped with a nameplate indicating the name of the area controlled by the valve. After the main valve and the zone valve are opened, high-pressure nitrogen drives the cylinder head valve of the CO2 cylinder to operate, and liquid CO2 flows out of the cylinder, through the manifold, main valve, and zone valve into the connecting pipeline 1, and then through the first supply unit 2 to the end nozzle 4 in the vehicle compartment.

[0065] In step S10, because the first supply unit 2 is equipped with a delay device, the system does not immediately release CO2 after the main valve and zone valves are opened, but releases it after a delay of 20 to 40 seconds. This delay provides a final safe evacuation window for any few personnel who may remain in the vehicle compartment, and also allows operators to use this time to confirm that all doors, windows, and ventilation openings are completely closed. After the delay ends, the high-pressure CO2 extinguishing agent is sprayed out at high speed from the terminal nozzle 4 in liquid form, and rapidly vaporizes and expands upon leaving the nozzle, its volume expanding to 400 to 500 times its liquid volume, thereby quickly filling the entire vehicle compartment space and achieving total flooding fire suppression.

[0066] Subsequently, after the CO2 system completes the release of the extinguishing agent, step S20 is executed: the main valve of the CO2 main pipe is closed, the connecting pipe 1 is connected through the second supply unit 3, and the fire pump is turned on. Fire water reaches the nozzle 43 in the fire-extinguishing area through the second supply unit 3 and the connecting pipe 1, and seawater is sprayed onto the fire area for cooling. Since the CO2 fire extinguishing system is a single-use system with a limited extinguishing agent reserve, it cannot be replenished to the vehicle compartment after release. Furthermore, new energy vehicles, especially lithium-ion battery electric vehicles, may still be in a critical state of thermal runaway after being exposed to high temperatures. Once the external temperature rises or the internal chemical reaction of the battery is reactivated, reignition is highly likely.

[0067] Therefore, the operator first closes the main valve on the CO2 main pipe to prevent the subsequently introduced fire-fighting seawater from backflowing into the CO2 cylinder group and drive pipeline, causing equipment damage. Then, the operator removes the flange blind plate of the pre-set branch port on the CO2 main pipe and connects the outlet of the ship's fire-fighting water system to the branch port through a detachable short pipe, thereby connecting the second supply unit 3 to the connecting pipeline 1. After the connection is completed, the fire pump is started. Under the pressure of the fire pump, the seawater from outside the ship flows through the fire-fighting water pipeline and the branch pipe of the second supply unit 3 into the CO2 main pipeline, and is transported along the connecting pipeline 1 to the end nozzle 4. The nozzle 43 continuously sprays seawater onto the fire area for physical cooling.

[0068] In step S20, to precisely control the endpoint of the cooling operation, a network of temperature sensors is pre-installed inside the vehicle compartment. These sensors can be K-type thermocouples or platinum resistance temperature sensors, with their probes positioned at the top of the vehicle compartment near the end nozzle 4 and in the middle of the compartment near the battery pack level, respectively, to collect and transmit real-time ambient temperature data for different heights and areas within the vehicle compartment. The signal output of the temperature sensors is electrically connected to the fire monitoring display panel in the ship's central control room, allowing operators to remotely read the temperature values ​​at each measuring point from a safe location. When the feedback data from the temperature sensors shows that the temperature inside the vehicle compartment has continuously decreased to the safe lower limit for lithium battery thermal runaway, the operator manually shuts off the fire pump and stops spraying water. However, considering the unique temperature fluctuation characteristics of lithium battery fires—that is, the residual chemical energy inside the battery may re-accumulate heat and cause a secondary temperature rise after the external open flame is extinguished—operators need to continuously monitor the temperature sensor readings. If a temperature rebound is detected, the fire pump can be restarted to resume water spraying for cooling, gradually reducing the overall temperature of the vehicle compartment through intermittent or continuous water spraying until the temperature stabilizes below the safe threshold for an extended period.

[0069] By sequentially executing steps S10 to S20, this cooling method, based on the traditional CO2 gas fire extinguishing process, introduces a post-cooling stage using seawater as the cooling medium. Without adding complex specialized cooling equipment, it utilizes the ship's existing fire-fighting water system to achieve long-term physical cooling of the high-temperature environment in the vehicle compartment, thereby effectively reducing the probability of reignition in new energy lithium battery fires and maximizing the safety of the transport vehicles and the ship itself. The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A carbon dioxide fire extinguishing and cooling system for new energy transport ships, characterized in that, include: Connecting pipe (1); The first supply unit (2) is connected to the carbon dioxide supply equipment at one end and to the connecting pipeline (1) at the other end. The second supply unit (3) is connected at one end to the fire water supply equipment and at the other end to the connecting pipe (1); and, The end nozzle (4) is connected at one end to the connecting pipe (1) and at the other end to the vehicle compartment.

2. The carbon dioxide fire extinguishing and cooling system for new energy transport vessels according to claim 1, characterized in that, The second supply unit (3) is connected to the connecting pipe (1) via a detachable short pipe.

3. The carbon dioxide fire extinguishing and cooling system for new energy transport vessels according to claim 1, characterized in that, The end nozzle (4) includes an end branch pipe (41), a nozzle seat (42) and a nozzle (43) that are interconnected. The end branch pipe (41) is connected to the connecting pipe (1), and the nozzle (43) is installed on the nozzle seat (42) to spray the medium in the end branch pipe (41).

4. The carbon dioxide fire extinguishing and cooling system for new energy transport vessels according to claim 1, characterized in that, A switching valve is provided on the connecting pipeline (1), and the switching valve is used to switch the connection between the first supply unit (2) or the second supply unit (3) and the connecting pipeline (1).

5. The carbon dioxide fire extinguishing and cooling system for new energy transport vessels according to claim 1, characterized in that, The second supply unit (3) is also connected to external seawater supply equipment.

6. A cooling method applied to the carbon dioxide fire extinguishing and cooling system for new energy transport vessels according to any one of claims 1-5, characterized in that, Includes the following steps: S10: Open the main valve and the partition valve in the carbon dioxide release valve box in sequence, and connect the connecting pipeline (1) through the first supply part (2) to start releasing carbon dioxide; S20: Close the main valve of the carbon dioxide main pipe, connect the connecting pipe (1) through the second supply section (3), turn on the fire pump, and the medium reaches the nozzle (43) of the fire extinguishing area through the second supply section (3) and the connecting pipe (1) to spray the medium to cool the fire area.

7. The cooling method according to claim 6, characterized in that, Before S10, preliminary preparations were carried out, including: S11: Open the carbon dioxide release valve box in the engine compartment. At the same time the carbon dioxide release valve box is opened, the system will automatically send a pre-alarm signal, a light pole alarm signal, and a wind and oil cut-off reminder signal. S12: Confirm that all personnel in the fire area have been evacuated; S13: Close all exit doors, windows and passageways of the fire site, and shut down the corresponding fans and oil pumps; S14: Open the gas cylinder box, and open nitrogen cylinder No. 1 and nitrogen cylinder No. 2 in sequence.

8. The cooling method according to claim 6, characterized in that, In S10, the system releases carbon dioxide with a delay of 20-40 seconds.

9. The cooling method according to claim 6, characterized in that, In the S20, a temperature sensor is installed inside the vehicle compartment. When the temperature drops to the lower limit of thermal runaway, the fire pump is shut down.

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