Flame arrester structure

Abstract

A flame arrester structure, comprising: a housing (1) provided with a pressure relief intake end (11), a pressure relief exhaust end (12) and a chamber (13) connecting the pressure relief intake end and the pressure relief exhaust end; a fire resistant structure arranged at the pressure relief exhaust end, the fire resistant structure comprising a plurality of fire resistant layers (2) successively arranged at intervals in the axial direction of the pressure relief exhaust end; and a flow guide structure arranged inside the housing, located upstream of the fire resistant structure in the flowing direction of a pressure relief airflow inside the housing, and used for dividing the pressure relief airflow inside the housing into multiple regional airflows that flow towards different regions of the fire resistant structure. When accidents such as fire occur in pressure relief positions of storage tanks of petrochemical devices, the flame arrester structure can provide long-duration fire resistance protection, thus preventing the accidents from further escalating and allowing more readiness time for emergency rescue.

Description

Fire-blocking structure

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] The present invention claims the benefit of Chinese patent applications 202311709174.0, 202311713798.X, 202311713610.1, 202311709183.X, 202311713805.6, 202311713619.2, 202311709192.9, 202323402124.6, and 202323402131.6 filed on December 13, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The invention belongs to the technical field of flame arresters, and in particular relates to a fire arrester structure. Background Art

[0004] During the loading and unloading process or when the ambient temperature rises, the gas pressure inside a petrochemical plant tank increases. To prevent overpressure or pressure buildup, a breather valve is typically installed on the tank top. However, an external ignition source could ignite the flammable gas exhaled from the tank, causing flames to propagate back into the tank, potentially causing a fire or explosion. Therefore, the breather valve must have a flame-blocking function, and all-weather flame-blocking breathers should be tested for overall flame-blocking properties.

[0005] However, most of the combustible gases exhaled from storage tanks are premixed combustible gases with high combustion calorific value. Existing pipe end flame arresters or flame arrester breathing valves generally have problems such as inability to withstand long-term burning. As a result, when a long-term combustion occurs at the pipe end and effective emergency rescue measures are in place, they cannot provide long-term burning protection, thereby causing the accident to further expand.

[0006] Summary of the Invention

[0007] The purpose of the present invention is to provide a fire-blocking structure that can provide long-term fire-resistant protection when an accident such as a fire at the pressure relief position of a petrochemical device storage tank occurs, so as to prevent the accident from further expanding and leave more preparation time for emergency rescue.

[0008] In order to achieve the above object, the present invention provides a fire-blocking structure comprising:

[0009] The housing is provided with a pressure relief air inlet end, a pressure relief air outlet end, and a cavity communicating with the pressure relief air inlet end and the pressure relief air outlet end;

[0010] a burn-resistant structure, provided at the pressure relief and exhaust end, the burn-resistant structure comprising a plurality of burn-resistant layers sequentially spaced apart along the axial direction of the pressure relief and exhaust end; and

[0011] A flow guide structure is arranged in the shell. Along the flow direction of the pressure relief airflow in the shell, the flow guide structure is located upstream of the burn-resistant structure and is used to divide the pressure relief airflow in the shell into multiple regional airflows flowing toward different areas of the burn-resistant structure.

[0012] Optionally, the flow guiding structure includes:

[0013] The cavity guide structure is arranged in the cavity and is used to divide the pressure relief airflow flowing into the cavity into an outer area airflow and an inner area airflow flowing in the outer area and inner area of ​​the cavity respectively, and make the flow rate of the outer area airflow greater than the flow rate of the inner area airflow, and / or make the flow rate of the outer area airflow greater than the flow rate of the inner area airflow.

[0014] Optionally, the flow guiding structure includes:

[0015] The cavity guide structure is arranged in the cavity and is used to divide the pressure relief airflow flowing into the cavity into an outer ring area airflow, an inner ring area airflow and a middle area airflow, which are distributed in sequence from the outside to the inside in the cavity, and make the flow rate of the outer ring area airflow, the flow rate of the middle area airflow, and the flow rate of the inner ring area airflow distributed from large to small, and / or make the flow rate of the outer ring area airflow, the flow rate of the middle area airflow, and the flow rate of the inner ring area airflow distributed from large to small.

[0016] Optionally, the flow guiding structure includes a cavity flow guiding structure provided in the cavity, and the cavity flow guiding structure includes:

[0017] The middle guide member is arranged in alignment with the pressure relief air inlet end, and is used to divide the pressure relief airflow flowing into the cavity from the pressure relief air inlet end into an outer area airflow and an inner area airflow flowing in the outer area and inner area of ​​the cavity respectively.

[0018] Optionally, the central flow guide is provided with an overflow structure, and the central flow guide is further configured to divide the pressure relief airflow into an outer ring area airflow, an inner ring area airflow and a central area airflow which are distributed sequentially from the outside to the inside in the cavity.

[0019] Optionally, the middle flow guide is a curved plate with the curved convex surface facing the pressure relief air inlet end.

[0020] Optionally, the middle flow guide member is a pressure relief valve disc for switching the on / off state between the cavity and the pressure relief air inlet end.

[0021] Optionally, the cavity guide structure further includes:

[0022] The first annular flow guide is arranged on the downstream side of the middle flow guide, and the outer circumferential wall of the first annular flow guide is spaced apart from the inner circumferential wall of the cavity. The first annular flow guide is used to further divide the outer area airflow and the inner area airflow into an outer annular area airflow, an inner annular area airflow and a middle area airflow distributed in sequence from the outside to the inside in the cavity.

[0023] Optionally, the cavity guide structure further includes:

[0024] The second annular flow guide is arranged on the downstream side of the first annular flow guide, the outer circumferential wall of the second annular flow guide is spaced apart from the inner circumferential wall of the cavity, and the outer ring radius of the second annular flow guide is larger than the outer ring radius of the first annular flow guide.

[0025] Optionally, the flow guiding structure includes:

[0026] The air inlet end guide structure is arranged in the pressure relief air inlet end, and is used to divide the pressure relief airflow flowing into the pressure relief air inlet end into an outer area airflow and an inner area airflow flowing in the outer area and inner area of ​​the pressure relief air inlet end respectively, and make the flow rate of the outer area airflow greater than the flow rate of the inner area airflow, and / or make the flow rate of the outer area airflow greater than the flow rate of the inner area airflow.

[0027] Optionally, the flow guiding structure includes:

[0028] The air inlet end guide structure is arranged in the pressure relief air inlet end, and is used to divide the pressure relief airflow flowing into the pressure relief air inlet end into an outer layer area airflow, an inner layer area airflow and a middle layer area airflow flowing in the outer layer area, the inner layer area and the middle layer area respectively in the pressure relief air inlet end, and make the flow rate of the outer layer area airflow, the flow rate of the middle layer area airflow and the flow rate of the inner layer area airflow distributed from large to small, and / or make the flow rate of the outer layer area airflow, the flow rate of the middle layer area airflow and the flow rate of the inner layer area airflow distributed from large to small.

[0029] Optionally, the flow-guiding structure includes an air intake end flow-guiding structure provided in the pressure relief air intake end, and the air intake end flow-guiding structure includes:

[0030] A first annular partition, wherein the outer peripheral wall of the first annular partition is spaced apart from the inner peripheral wall of the pressure relief air inlet end, and the first annular partition is used to divide the pressure relief airflow flowing into the pressure relief air inlet end into an outer area airflow flowing between the inner peripheral wall of the pressure relief air inlet end and the outer peripheral wall of the first annular partition and an inner area airflow flowing inside the first annular partition.

[0031] Optionally, the air inlet end guide structure further includes:

[0032] The second annular partition is arranged inside the first annular partition and is spaced apart from the inside and outside of the first annular partition. The second annular partition is used to divide the internal area airflow into an inner layer area airflow flowing between the first annular partition and the second annular partition and an intermediate area airflow flowing inside the second annular partition.

[0033] Optionally, the burn-resistant layer includes an outer circulation structure, an inner circulation structure, and an intermediate circulation structure for respectively circulating the airflow in the outer layer area, the airflow in the inner layer area, and the airflow in the intermediate area; the porosities of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are σ1, σ2, and σ3, respectively; and the circulation areas of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are S1, S2, and S3, respectively;

[0034] The inlet split ratio of the annular area between the inner circumferential wall of the pressure relief inlet end and the outer circumferential wall of the first annular partition, the inlet split ratio of the annular area between the first annular partition and the second annular partition, and the inlet split ratio of the inner area of ​​the second annular partition are a, b, and c respectively;

[0035] The total flow area at the inlet end of the inlet end guide structure is S0; it satisfies:

[0036] (S1*σ1) / (S0*a)≤2 / 3;

[0037] (S2*σ2) / (S0*b)≥5;

[0038] 1≤(S3*σ3) / (S0*c)≤3.

[0039] Optionally, the burn-resistant layer includes an outer ring region of the burn-resistant layer and an inner ring region of the burn-resistant layer located inside the outer ring region of the burn-resistant layer, and the porosity of the outer ring region of the burn-resistant layer is greater than the porosity of the inner ring region of the burn-resistant layer.

[0040] Optionally, the inner area of ​​the burn-resistant layer includes an inner ring area of ​​the burn-resistant layer and a middle area of ​​the burn-resistant layer. The outer ring area of ​​the burn-resistant layer, the inner ring area of ​​the burn-resistant layer and the middle area of ​​the burn-resistant layer are arranged in sequence from outside to inside, and the porosity of the outer ring area of ​​the burn-resistant layer, the porosity of the middle area of ​​the burn-resistant layer and the porosity of the inner ring area of ​​the burn-resistant layer are set from large to small.

[0041] Optionally, the fire-blocking structure further includes:

[0042] The heat-insulating support structure is arranged between two adjacent burn-resistant layers and contacts the two adjacent burn-resistant layers.

[0043] Optionally, the thermal insulation support structure is a multi-layer thermal insulation support structure, which includes a plurality of thermal insulation support units stacked in sequence along the axial direction; or, the multi-layer thermal insulation support structure includes a thermal insulation support main body and a thermal insulation support protrusion formed by protruding from the thermal insulation support main body along the axial direction.

[0044] Optionally, the thermal insulation support structure forms point contact, line contact or surface contact with the burn-resistant layer.

[0045] Optionally, the burn-resistant layer includes an outer ring area of ​​the burn-resistant layer and an inner area of ​​the burn-resistant layer located inside the outer ring area of ​​the burn-resistant layer. The outer ring area of ​​the burn-resistant layer can allow pressure relief airflow to circulate, and the inner area of ​​the burn-resistant layer is a closed insulation area.

[0046] Optionally, the burn-resistant layer includes a first closed thermal insulation disk and multiple first fire-retardant disks, the outer ring area of ​​the burn-resistant layer and the inner area of ​​the burn-resistant layer are both arranged on the first closed thermal insulation disk, and the outer ring area of ​​the burn-resistant layer of the first closed thermal insulation disk is provided with multiple first embedding openings formed in sequence along the circumferential direction, and the multiple first fire-retardant disks are embedded in the multiple first embedding openings one by one.

[0047] Optionally, each of the burn-resistant layers includes an outer ring area of ​​the burn-resistant layer, an inner ring area of ​​the burn-resistant layer and a middle area of ​​the burn-resistant layer arranged in sequence from the outside to the inside. The outer ring area of ​​the burn-resistant layer and the middle area of ​​the burn-resistant layer can both provide for the circulation of pressure relief airflow, and the inner ring area of ​​the burn-resistant layer is a closed insulation area.

[0048] Optionally, the burn-resistant layer includes a second closed thermal insulation disk, multiple second fire-retardant disks and a single third fire-retardant disk, the outer ring area of ​​the burn-resistant layer, the inner ring area of ​​the burn-resistant layer and the middle area of ​​the burn-resistant layer are all arranged on the second closed thermal insulation disk, and the outer ring area of ​​the burn-resistant layer of the second closed thermal insulation disk is provided with multiple second embedding openings formed in sequence along the circumferential direction, and multiple second fire-retardant disks are embedded in the multiple second embedding openings one by one, and the middle area of ​​the burn-resistant layer of the second closed thermal insulation disk is provided with a third embedding opening, and the third fire-retardant disk is embedded in the third embedding opening.

[0049] Optionally, the burn-resistant layer includes a fire-retardant ring, a closed thermal insulation ring and a fourth fire-retardant disk nested in sequence from the outside to the inside, the outer ring area of ​​the burn-resistant layer is arranged on the fire-retardant ring, the inner ring area of ​​the burn-resistant layer is arranged on the closed thermal insulation ring, and the middle area of ​​the burn-resistant layer is arranged on the fourth fire-retardant disk.

[0050] Optionally, the burn-resistant layer includes a stacked porous burn-resistant layer, which includes a first shell and a plurality of stacked particles stacked in the first shell. The upstream side wall and the downstream side wall of the first shell are both provided with a plurality of first shell through holes, and the diameter of the first shell through holes is smaller than the diameter of the stacked particles.

[0051] Optionally, the distance between the upstream inner sidewall and the downstream inner sidewall of the first shell is the same as the total stacking thickness of the plurality of stacked particles along the axial direction of the stacked porous burn-resistant layer.

[0052] Optionally, the burn-resistant layer includes a stacked porous burn-resistant layer, which includes a second shell and a plurality of lightweight spheres stacked in the second shell and capable of rotating under the drive of the pressure relief airflow. The upstream side wall and the downstream side wall of the second shell are both provided with a plurality of second shell through holes, and the diameter of the second shell through holes is smaller than the diameter of the lightweight spheres.

[0053] Optionally, among the multiple burn-resistant layers, the burn-resistant layer located at the most downstream is formed as a combustion side burn-resistant layer, and the combustion side burn-resistant layer includes a burn-resistant layer disc portion and a burn-resistant layer convex portion connected to the downstream side of the burn-resistant layer disc portion, and the downstream side surface of the burn-resistant layer convex portion is a local spherical surface protruding toward the downstream.

[0054] Through the above technical solution, when the flammable pressure relief airflow is continuously discharged through the pressure relief exhaust end and ignited on the downstream side of the combustion side burn-resistant layer, the combustion side burn-resistant layer will be burned for a long time. Due to the provision of a diversion structure in the fire-blocking structure of the present invention, compared with the long-term combustion condition of the existing flame arrester in which the combustion heat is concentrated in a local area (usually the middle area) of the fire-blocking structure, which makes it difficult for the combustion heat to dissipate and even causes the fire-blocking structure to be burned through, the pressure relief airflow flowing into the shell can be actively diverted, and the diverted multiple regional airflows can flow through different areas of the burn-resistant structure, thereby dispersing the heat in the burn-resistant structure, so as to effectively reduce the risk of tempering and burn-through, and effectively extend the fire-blocking time. It can be seen that the fire-blocking structure of the present invention can provide long-term burn-resistant protection when an accident such as a fire at the pressure relief position of a petrochemical device storage tank occurs, thereby preventing the accident from further expanding and leaving more preparation time for emergency rescue.

[0055] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without inventive work. In the accompanying drawings:

[0057] FIG1 is a schematic diagram of a fire-blocking structure according to a specific embodiment of the present invention;

[0058] FIG2 is a schematic diagram of another fire barrier structure in a specific embodiment of the present invention, in which the fire barrier structure is provided with two protective side burn-resistant layers;

[0059] FIG3 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which the fire-blocking structure is provided with a central flow guide;

[0060] FIG4 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which the fire-blocking structure is provided with a central flow guide, and the central flow guide is a curved plate with a flow-through structure;

[0061] FIG5 is an axial schematic diagram of a middle flow guide member in a specific embodiment of the present invention, wherein the middle flow guide member includes a middle circular area provided with a flow-through structure;

[0062] FIG6 is a schematic diagram of a fire-blocking structure applied to an exhalation valve in a specific embodiment of the present invention;

[0063] FIG7 is a schematic diagram of a fire-blocking structure applied as a breathing valve in a specific embodiment of the present invention;

[0064] FIG8 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which the fire-blocking structure is provided with a middle flow guide and a first annular flow guide;

[0065] FIG9 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which the fire-blocking structure is provided with a central flow guide, a first annular flow guide, and two protective side burn-resistant layers;

[0066] FIG10 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which the fire-blocking structure includes a central flow guide, a first annular flow guide, and a second annular flow guide;

[0067] FIG11 is a diagram showing regional airflow distribution within a cavity when a cavity guide structure is provided in a fire-blocking structure according to a specific embodiment of the present invention;

[0068] FIG12 is a diagram showing regional airflow distribution within a cavity when another fire-blocking structure is provided with a cavity guide structure in a specific embodiment of the present invention;

[0069] FIG13 is a schematic diagram of structural parameters of the fire-blocking structure in FIG3 ;

[0070] FIG14 is a schematic diagram of an air intake end guide structure according to a specific embodiment of the present invention;

[0071] FIG15 is a diagram showing regional airflow distribution within a cavity of a fire-blocking structure when an air inlet guide structure is provided in a specific embodiment of the present invention;

[0072] FIG16 is a diagram showing regional airflow distribution within a cavity when another fire-blocking structure is provided with an air inlet guide structure in a specific embodiment of the present invention;

[0073] 17 to 19 are axial schematic diagrams of three optional thermal insulation support structures in specific embodiments of the present invention;

[0074] 20 and 21 are side views of two other optional thermal insulation support structures in a specific embodiment of the present invention;

[0075] FIG22 is a schematic diagram of another fire barrier structure in a specific embodiment of the present invention, in which each fire-resistant layer is provided with an outer ring area and an inner area of ​​the fire-resistant layer, and the inner area of ​​the fire-resistant layer can be a closed heat-insulating area;

[0076] FIG23 is an axial schematic diagram of a burn-resistant layer according to a specific embodiment of the present invention, wherein the burn-resistant layer includes a first closed heat-insulating disk and a plurality of first fire-blocking disks;

[0077] FIG24 is a schematic diagram of another fire-blocking structure in a specific embodiment of the present invention, in which each fire-resistant layer is provided with an outer ring area, an inner ring area, and an intermediate area, and the inner ring area can be a closed heat-insulating area.

[0078] FIG25 is an axial schematic diagram of another fire-resistant layer in a specific embodiment of the present invention, in which the fire-resistant layer includes a fire-blocking ring, a closed heat-insulating ring, and a fourth fire-blocking disk;

[0079] FIG26 is an axial schematic diagram of another burn-resistant layer in a specific embodiment of the present invention, in which the burn-resistant layer includes a second closed heat-insulating disk, a plurality of second fire-blocking disks, and a single third fire-blocking disk;

[0080] FIG27 is a schematic diagram of a stacked porous burn-resistant layer according to a specific embodiment of the present invention;

[0081] FIG28 is a schematic diagram of a combustion-side burn-resistant layer according to a specific embodiment of the present invention, in which the combustion-side burn-resistant layer is provided with a burn-resistant layer disc portion and a burn-resistant layer convex portion;

[0082] FIG29 is a schematic diagram of a fire barrier structure used for comparative experiments in a specific embodiment of the present invention. In the fire barrier structure in the figure, no spacing is left between the combustion-side burn-resistant layer and the protection-side burn-resistant layer.

[0083] DESCRIPTION OF THE REFERENCE NUMERALS 1. Shell; 11. Pressure relief inlet end; 12. Pressure relief exhaust end; 13. Cavity; 2. Burn-resistant layer; 21a. Combustion-side burn-resistant layer; 21b. Protective-side burn-resistant layer; 22a. Outer ring area of ​​the burn-resistant layer; 22b. Inner ring area of ​​the burn-resistant layer; 22c. Intermediate area of ​​the burn-resistant layer; 23a. First closed heat-insulating disk; 23b. First fire-stop disk; 24a. Second closed heat-insulating disk; 24b. Second fire-stop disk; 24c. Third fire-stop disk; 25a. Fire-stop ring; 25b. Closed heat-insulating ring; 25c. Fourth fire-stop disk; 26a. First shell; 26b. Accumulated particles; 27a. Disc portion of the burn-resistant layer; 27b. Convex portion of the burn-resistant layer; 3. Insulation support structure; 31. Insulation support unit; 32a. Insulation support body; 32b. Insulation support protrusion; 4. Middle flow guide; 41 Flow structure, 42 Bend plate, 43 Pressure relief valve disc; 5 First annular flow guide; 6 Second annular flow guide; 7 First annular baffle; 8 Second annular baffle; G11 Outer area airflow, G12 Inner area airflow; G21 Outer annular area airflow, G22 Inner annular area airflow, G23 Middle area airflow; G31 Outer area airflow, G32 Inner area airflow, G321 Inner area airflow, G322 Middle area airflow DETAILED DESCRIPTION

[0084] The following describes in detail specific embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are intended solely to illustrate and explain the present invention and are not intended to limit the present invention. Furthermore, it should be noted that references to positions such as "upstream," "downstream," and "most downstream" herein are based on the direction of the pressure relief airflow through the fire-blocking structure.

[0085] The fire-blocking structure according to the present invention will be described below with reference to the accompanying drawings.

[0086] After analysis, it is found that when the existing pipe end flame arrester or flame arrester breathing valve burns for a long time, the combustion heat is transferred in three directions: one is transferred to the inside of the flame arrester through heat conduction and heat radiation, the second is carried away by part of the combustible gas discharged by the flame arrester, and the third is dissipated into the outside atmosphere through heat conduction and heat radiation.

[0087] The second and third heat transfer directions mentioned above both help prevent combustion heat from accumulating in the flame arrester, improving its flame-blocking effectiveness. The first heat transfer direction, on the other hand, transfers combustion heat into the flame arrester, increasing the risk of flashback and burn-through.

[0088] However, the existing pipe end flame arrester or fire-arresting breathing valve is restricted by its fire-arresting structure and internal structure. When the fire-arresting structure burns, the transfer direction of the combustion heat is mainly the first one mentioned above. Therefore, the combustion heat will quickly accumulate in the fire-arresting structure and will accumulate in a local area of ​​the fire-arresting structure (usually the middle area), which is prone to burn-through in this local area.

[0089] To address the deficiencies in the prior art, the fire-blocking structure of the present invention is optimized primarily based on two design directions: one is to enhance heat transfer in the second and third heat transfer directions as much as possible, i.e., to enhance the dissipation of combustion heat; the other is to weaken heat transfer in the first heat transfer direction as much as possible, i.e., to weaken the transfer of combustion heat to the interior of the fire-blocking structure.

[0090] A number of optional embodiments of the fire-blocking structure of the present invention will be provided below. Each embodiment adopts at least one of the two design directions mentioned above, and can effectively extend the fire-blocking time.

[0091] In each optional embodiment, first referring to Figure 1, the basic structure of the fire-blocking structure includes a shell 1 and a burn-resistant structure. Specifically, the shell 1 is provided with a pressure relief air inlet 11, a pressure relief exhaust 12, and a cavity 13 connecting the pressure relief air inlet 11 and the pressure relief exhaust 12. When the pressure of the combustible gas needs to be released through the fire-blocking structure, the pressure relief airflow passes through the pressure relief air inlet 11, the cavity 13, and the pressure relief exhaust 12 in sequence. In addition, the burn-resistant structure is provided at the pressure relief exhaust 12. In order to ensure that the pressure relief airflow can be discharged from the pressure relief exhaust 12, the burn-resistant structure needs to be provided with structures such as holes and gaps.

[0092] When an external ignition source ignites the pressure relief airflow on the downstream side of the fire-resistant structure, there are two operating conditions:

[0093] One is a non-long-term fire-resistant working condition, in which the pressure relief airflow is not continuously discharged through the pressure relief exhaust port 12. Therefore, under the quenching and outward heat transfer effect of the fire-resistant structure, the fire-resistant structure can prevent the flame from spreading to the upstream of the fire-resistant structure (i.e., the interior of the fire-blocking structure);

[0094] The other is a long-term burn-resistant condition, in which the pressure relief airflow is continuously discharged through the pressure relief exhaust port 12, and flames will exist for a long time on the downstream side of the burn-resistant structure. The burn-resistant structure may not be able to prevent the flames from spreading to the upstream of the burn-resistant structure, and the flames may even burn through the burn-resistant structure. These situations are likely to cause more serious accidents such as tank fires or explosions.

[0095] The following are several optional embodiments that can effectively extend the fire arresting time:

[0096] Airflow control method 1 (cavity guide structure)

[0097] 3 and 11 , the fire-blocking structure may include a cavity flow-guiding structure disposed within the cavity 13. Specifically, the cavity flow-guiding structure may include a central flow-guiding member 4 positioned in alignment with the pressure relief air inlet end 11. Under the guidance of the central flow-guiding member 4, the pressure relief airflow flowing from the pressure relief air inlet end 11 into the cavity 13 may be divided into an outer region airflow G11 flowing in the outer region of the cavity 13 and an inner region airflow G12 flowing in the inner region of the cavity 13.

[0098] Compared with the long-term combustion conditions of existing flame arresters, in which the combustion heat is concentrated in a local area (usually the middle area) of the fire-blocking structure, making it difficult for the combustion heat to dissipate and even causing the fire-blocking structure to be burned through, the fire-blocking structure of this embodiment can actively divert the pressure relief airflow flowing into the cavity 13 by setting a middle guide member 4. The diverted outer area airflow G11 and inner area airflow G12 can disperse the heat in the burn-resistant structure to different areas, thereby effectively reducing the risk of tempering and burn-through, and effectively extending the fire-blocking time.

[0099] Further, referring to Figures 4 and 12, the middle flow guide 4 may be provided with a flow structure 41 (such as multiple holes or gaps) throughout. At this time, the pressure relief airflow flowing into the cavity 13 from the pressure relief air inlet end 11 will pass through the middle flow guide 4 from the outer periphery of the middle flow guide 4 and the flow structure 41. The pressure relief airflow passing through the outer periphery of the middle flow guide 4 will be split into two airflows, of which the airflow in the outer area is the outer ring area airflow G21, and part of the airflow in the inner area will converge with the pressure relief airflow passing through the flow structure 41, so that the airflow in the inner area is further formed into two split airflows with different flow rates and / or flow rates, namely the inner ring area airflow G22 and the middle area airflow G23.

[0100] In other words, overall, after the pressure relief airflow passes through the central flow guide 4 with the flow-through structure 41, the cavity 13 downstream of the central flow guide 4 will have an outer annular region airflow G21, an inner annular region airflow G22, and a central region airflow G23 distributed from the outside to the inside. This flow pattern disperses heat from the fire-resistant structure to more diverse areas, further extending the fire-retardant duration.

[0101] Referring to Figure 4 , to reduce the pressure relief airflow resistance, the central air guide 4 can be configured as a curved plate 42 (e.g., an arc-shaped plate), with the curved convex surface of the curved plate 42 facing the pressure relief air inlet 11. This reduces the airflow resistance as the pressure relief airflow passes through the outer peripheral edge of the central air guide 4, ensuring a high pressure relief speed for the fire arrester structure and more quickly removing heat from the cavity 13.

[0102] In addition to being configured as a curved plate 42 , the middle flow guide 4 may also be configured as other streamlined shapes, such as a cone, a spindle, a teardrop, etc., which is not limited in the present invention.

[0103] 6 and 7 , when the fire-blocking structure is used in a breathing valve (or exhalation valve), the central flow guide 4 can also serve as the breathing valve (or exhalation valve)'s pressure relief valve disc 43 to switch the connection between the cavity 13 and the pressure relief inlet port 11. When the pressure relief valve disc 43 moves downstream to open, connecting the cavity 13 with the pressure relief inlet port 11, the pressure relief valve disc 43 performs the aforementioned flow diversion and diversion functions.

[0104] 5 , the flow-through structure 41 may include a plurality of flow-through holes formed in the central circular area of ​​the central flow guide 4. In addition to roughly limiting the flow range of the central area airflow G23 to the central cylindrical area of ​​the cavity 13, the flow velocity and flow rate of the central area airflow G23 may also be adjusted by designing different aperture sizes and hole density.

[0105] In a specific embodiment, the total flow area of ​​the flow structure 41 is no more than one-third of the flow area of ​​the pressure relief air inlet end 11, so as to prevent the flow rate of the air flow G23 in the middle area from being too large, thereby preventing the middle area of ​​the refractory structure from overheating and failing to effectively solve the problem.

[0106] In a specific embodiment, the axial projection area of ​​the central flow guide 4 is not larger than the axial projection area of ​​the pressure relief air inlet end 11, so as to prevent the radial size of the central flow guide 4 from being too large and affecting the discharge speed of the pressure relief airflow.

[0107] In a specific embodiment, referring to FIG13 , the diameter of the central guide member 4 is D1, the distance between the central guide member 4 and the inner wall of the upstream end of the cavity 13 is H1, the distance between the central guide member 4 and the inner wall of the downstream end of the cavity 13 is H2, the inner diameter of the cavity 13 is D, and the inner diameter of the pressure relief inlet end 11 is d, satisfying:

[0108] Among them, e is a natural constant, and its value is approximately 2.718.

[0109] The above relationship primarily defines the optimal size and position of the central flow guide 4. Typically, to achieve better flow performance, the inner diameter D of the cavity 13 is at least twice the inner diameter d of the pressure relief inlet end 11. However, without the central flow guide 4, the pressure relief airflow entering the cavity 13 from the pressure relief inlet end 11 will experience a higher velocity in the central region than in the outer annular region of the cavity. This results in the pressure relief airflow being concentrated in the central region of the burn-resistant structure, resulting in a significant pressure drop.

[0110] The above relationship is designed from the perspective of optimizing the flow field distribution, and a specific range of the diameter D1 of the middle guide member 4 is designed, and the range of the distance H1 between the middle guide member 4 and the inner wall of the upstream end of the cavity 13 and the range of the distance H2 between the middle guide member 4 and the inner wall of the downstream end of the cavity 13 are respectively limited.

[0111] Specifically, the diameter D1 is mainly considered to ensure that the main airflow of the pressure relief airflow hits the middle guide member 4 and then flows from the outer periphery of the middle guide member 4 to the downstream. If the diameter D1 is too large, the circulation space of the outer airflow will be reduced. Therefore, based on experimental data and basic principles of fluid mechanics, the diameter D1 is limited to the above range.

[0112] The spacing H1 is mainly considered to have a flow area required for the pressure relief airflow to pass therethrough, which should be larger than the incoming flow area of ​​the pressure relief air inlet end 11 to reduce the pressure loss caused by the 90° bend.

[0113] The spacing H2 takes into account that the incoming flow must be fully developed after passing through the middle guide member 4, so that the refracted flow generated by the airflow hitting the inner wall of the downstream end of the cavity 13 has a good disturbing effect on the airflow, thereby forming a relatively consistent flow velocity distribution. It is mainly derived through fluid mechanics theory, numerical simulation and experimental results.

[0114] 8 , 9 , and 12 , the cavity flow guide structure may further include a first annular flow guide 5 disposed downstream of the central flow guide 4 . The outer circumferential wall of the first annular flow guide 5 is spaced apart from the inner circumferential wall of the cavity 13 . When the central flow guide 4 has already separated the outer region airflow G11 and the inner region airflow G12 , the outer region airflow G11 and the inner region airflow G12 can be further separated by the first annular flow guide 5 as they pass through the first annular flow guide 5 . At this time, the airflow of the outer part of the outer area airflow G11 flows downstream through the gap area between the outer circumferential wall of the first annular guide member 5 and the inner circumferential wall of the cavity 13, and this part of the airflow is the outer annular area airflow G21; while the airflow of the inner part of the outer area airflow G11 and the airflow of the outer part of the inner area airflow G12 are diverted when passing through the inner ring periphery of the first annular guide member 5, and the diverted airflow close to the inner ring periphery of the first annular guide member 5 is the inner annular area airflow G22, and the diverted airflow away from the inner ring periphery of the first annular guide member 5 (that is, the diverted airflow flowing in the middle area of ​​the cavity 13) is the middle area airflow G23.

[0115] In other words, overall, after the pressure relief airflow is split by the central guide 4 and the first annular guide 5, the area of ​​the cavity 13 downstream of the first annular guide 5 will have an outer annular region airflow G21, an inner annular region airflow G22, and a central region airflow G23, distributed from the outside to the inside. This flow pattern disperses heat from the fire-resistant structure to more diverse areas, further extending the fire arresting time.

[0116] It should be noted that when the middle guide member 4 is provided with a flow-through structure 41 and the cavity guide structure is provided with a first annular guide member 5, an outer ring area airflow G21, an inner ring area airflow G22 and a middle area airflow G23 distributed from the outside to the inside will also be formed in the area of ​​the cavity 13 downstream of the first annular guide member 5. This is because the flow-through structure 41 mainly affects the flow rate and / or flow velocity of the middle area airflow G23.

[0117] Referring to Figure 10 , the cavity flow guide structure may further include a second annular flow guide 6 disposed downstream of the first annular flow guide 5. The outer circumferential wall of the second annular flow guide 6 is spaced apart from the inner circumferential wall of the cavity 13, and the outer ring radius of the second annular flow guide 6 is greater than the outer ring radius of the first annular flow guide 5. Clearly, the second annular flow guide 6 can further guide and divert the flow fields of the outer annular region airflow G21, the inner annular region airflow G22, and the middle region airflow G23 to adjust the flow rate and / or flow velocity of each region of airflow, or further divide the airflow into more regional streams to disperse the heat in the fire-resistant structure as evenly as possible, thereby achieving an excellent effect of extending the fire-retardant duration.

[0118] The present invention only lists some optional forms of the cavity guide structure for illustration. It is understandable that other cavity guide structures that can also divide the pressure relief airflow in the cavity 13 into multiple regional airflows should also fall within the scope of the present invention.

[0119] Airflow control method 2 (intake end guide structure)

[0120] 14 and 15 , the fire-blocking structure may include an air intake guide structure disposed within the pressure relief air intake port 11. Specifically, the air intake guide structure may include a first annular baffle 7, the outer circumferential wall of which is spaced from the inner circumferential wall of the pressure relief air intake port 11. In this manner, the pressure relief airflow flowing into the pressure relief air intake port 11, guided by the first annular baffle 7, is divided into an outer region airflow G31 flowing between the inner circumferential wall of the pressure relief air intake port 11 and the outer circumferential wall of the first annular baffle 7, and an inner region airflow G32 flowing within the first annular baffle 7.

[0121] Compared with the long-term combustion condition of the existing flame arrester, in which the combustion heat is concentrated in a local area (usually the middle area) of the fire-blocking structure, which makes it difficult to dissipate the combustion heat and even causes the fire-blocking structure to be burned through, the fire-blocking structure of this embodiment can actively divert the pressure relief airflow flowing into the pressure relief air inlet end 11 by setting a first annular partition 7. The diverted outer area airflow G31 and the internal area airflow G32 can disperse the heat in the burn-resistant structure to different areas, thereby effectively reducing the risk of tempering and burn-through, effectively extending the fire-blocking time, and achieving long-term fire-blocking.

[0122] Furthermore, referring to Figures 14 and 16 , the air inlet-end guide structure may further include a second annular baffle 8 disposed within the first annular baffle 7, spaced apart from the first annular baffle 7. In this case, the inner region airflow G32, guided by the second annular baffle 8, can be further divided into an inner region airflow G321 flowing between the first and second annular baffles 7, 8, and an intermediate region airflow G322 flowing within the second annular baffle 8.

[0123] In other words, overall, when the pressure relief airflow passes through the inlet-end flow guide structure equipped with the first annular baffle 7 and the second annular baffle 8, the pressure relief inlet end 11 will have an outer region airflow G31, an inner region airflow G321, and an intermediate region airflow G322 distributed from the outside to the inside. This flow pattern disperses the heat in the fire-resistant structure to more different areas, further extending the fire-retardant duration.

[0124] In a specific embodiment, the structural parameter relationship between the burn-resistant structure and the air intake end guide structure is defined. Specifically, the burn-resistant structure may include an outer circulation structure, an inner circulation structure, and an intermediate circulation structure for respectively ventilating the outer region airflow G31, the inner region airflow G321, and the intermediate region airflow G322; the porosity of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are σ1, σ2, and σ3, respectively; and the flow areas of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are S1, S2, and S3, respectively.

[0125] In addition, the inlet end diversion ratio of the annular area between the inner circumferential wall of the pressure relief inlet end 11 and the outer circumferential wall of the first annular partition 7, the inlet end diversion ratio of the annular area between the first annular partition 7 and the second annular partition 8, and the inlet end diversion ratio of the inner area of ​​the second annular partition 8 are a, b, and c, respectively.

[0126] Furthermore, the total flow area of ​​the inlet end of the air intake end guide structure is S0.

[0127] Based on the principle of flow conservation, the following relationship is set so that the pressure relief airflow rate flowing into the annular area between the inner peripheral wall of the pressure relief air inlet end 11 and the outer peripheral wall of the first annular partition 7 is equal to the pressure relief airflow rate flowing through the outer layer circulation structure of the burn-resistant structure, the pressure relief airflow rate flowing into the annular area between the first annular partition 7 and the second annular partition 8 is equal to the pressure relief airflow rate flowing through the inner layer circulation structure of the burn-resistant structure, and the pressure relief airflow rate flowing into the inner area of ​​the second annular partition 8 is equal to the pressure relief airflow rate flowing through the middle circulation structure of the burn-resistant structure. The specific relationship is as follows:

[0128] (S1*σ1) / (S0*a)≤2 / 3;

[0129] (S2*σ2) / (S0*b)≥5;

[0130] 1≤(S3*σ3) / (S0*c)≤3.

[0131] It should be noted that the air inlet end guide structure can also be provided with a greater number of annular baffles in addition to the first annular baffle 7 and the second annular baffle 8 to divide more regional airflows and disperse the heat in the fire-resistant structure as evenly as possible to achieve an excellent effect of extending the fire-retardant time.

[0132] The present invention only lists some optional forms of the air intake end guide structure for illustration. It can be understood that other air intake end guide structure forms that can also divide the pressure relief airflow in the pressure relief air intake end 11 into multiple regional airflows should also fall within the scope of the present invention.

[0133] Furthermore, in addition to the cavity flow-guiding structure and the air inlet end flow-guiding structure provided above, other forms of flow-guiding structures may be provided within the housing 1. For example, an integral housing flow-guiding structure may be designed that occupies space in both the cavity 13 and the pressure-relief air inlet end 11. In other words, the present invention is not limited to the specific form of the flow-guiding structure provided within the housing 1. As long as the flow-guiding structure is located upstream of the burn-resistant structure and is capable of dividing the pressure-relief airflow within the housing 1 into multiple regional airflows flowing toward different regions of the burn-resistant structure, the effect of extending the fire-retardant duration can be achieved.

[0134] Airflow control method three (porosity distribution of burn-resistant structure)

[0135] By providing multiple refractory layer partitions with varying porosities within the refractory structure, the pressure relief airflow can have varying velocities and / or flow rates when passing through the partitions. For example, in areas of the refractory structure prone to localized overheating during combustion, the porosity of these areas can be relatively low to reduce the flow rate through them, thereby reducing the combustion heat in those areas.

[0136] Compared with the long-term combustion conditions of existing flame arresters, in which the combustion heat is concentrated in a local area (usually the middle area) of the fire-resistant structure, making it difficult for the combustion heat to dissipate and even causing the fire-resistant structure to be burned through, the fire-resistant structure of this embodiment can actively divert the pressure relief airflow flowing through the fire-resistant structure by reasonably setting the porosity of multiple fire-resistant layer partitions, thereby preventing local overheating of the fire-resistant structure, thereby effectively reducing the risk of tempering and burn-through, effectively extending the fire-resistant time, and achieving long-term fire-resistant.

[0137] Referring to Figure 22 , the burn-resistant layer partitions may include an outer ring zone 22a and an inner zone located within the outer ring zone 22a. Thus, when the pressure relief airflow flows through the burn-resistant structure, it is divided into two regional airflows, which are discharged through the outer ring zone 22a and the inner zone, respectively.

[0138] Further, referring to Figure 24 , the inner area of ​​the burn-resistant layer may include an inner ring area 22b and a middle area 22c. In this case, the outer ring area 22a, the inner ring area 22b, and the middle area 22c are arranged from the outside to the inside. Thus, when the pressure relief airflow flows through the burn-resistant structure, it is divided into three regional airflows, which are discharged through the outer ring area 22a, the inner ring area 22b, and the middle area 22c, respectively.

[0139] In a specific embodiment, the radius of the middle zone 22c of the burn-resistant layer is r1, the outer radius of the inner ring zone 22b of the burn-resistant layer is r2, and the outer radius of the outer ring zone 22a of the burn-resistant layer is R, satisfying the following: 0≤r1≤R / 3, R / 3≤r2≤2R / 3. In particular, when r1=0, it is equivalent to the burn-resistant layer partition including the outer ring zone 22a of the burn-resistant layer and the inner zone of the burn-resistant layer, and the inner zone of the burn-resistant layer is not further divided into the inner ring zone 22b of the burn-resistant layer and the middle zone 22c of the burn-resistant layer.

[0140] It should be noted that the fire-resistant structure can be divided into more annular fire-resistant layer partitions to divide more regional airflows and disperse the heat in the fire-resistant structure as evenly as possible to achieve an excellent effect of extending the fire-retardant time.

[0141] The specific structural forms of the outer annular region 22a, the inner region 22b, and the intermediate region 22c of the refractory layer can be found in the embodiment of radial heat insulation of the refractory structure described later and will not be described in detail here. It is understood that other refractory layer partitioning structures that can also divide the pressure relief airflow into multiple regional airflows are also within the scope of the present invention.

[0142] Flow rate and flow distribution under airflow control

[0143] Experiments conducted by the designers of the present invention have shown that when the fire-resistant structure burns, the faster the flow rate of the pressure relief airflow through the fire-resistant structure, the less combustion heat is transferred to the interior of the fire-resistant structure. Theoretical analysis shows that this is mainly because the airflow with a high flow rate can carry away the combustion heat accumulated in the fire-resistant structure more quickly, thereby accelerating the dissipation of the combustion heat to the outside.

[0144] Therefore, when the pressure relief airflow is divided into multiple regional airflows through active diversion technology (i.e., the aforementioned airflow control methods one, two, and three), the porosity distribution of the cavity guide structure, the air inlet end guide structure, or the burn-resistant structure can be adjusted in structure and parameters so that the flow rate distribution of the airflow in each region meets the need to extend the fire-blocking time.

[0145] Two optional flow rate distribution forms are available to extend the fire arresting time:

[0146] The first distribution form is to direct the high-velocity, high-flow area of ​​air to the outer area of ​​the refractory structure, and direct the low-velocity, low-flow area of ​​air to the inner area of ​​the refractory structure. In particular, no air flow may pass through the inner area of ​​the refractory structure.

[0147] When the refractory structure burns, the high-flow regional airflow will pass through the outer area of ​​the refractory structure, which already has a relatively high heat dissipation efficiency, at high speed, removing a large amount of combustion heat more quickly and further increasing the rate of heat dissipation. The low-flow regional airflow will pass through the inner area of ​​the refractory structure (including the middle area) at a low speed, or no regional airflow will pass through the inner area of ​​the refractory structure. Compared with existing flame arresters that pass a large flow of pressure relief air through the middle area of ​​the refractory structure, this can effectively solve the problem of local heat concentration in the middle area of ​​the refractory structure and effectively reduce the risk of tempering and burn-through of the middle area.

[0148] The second distribution form is to direct the high-velocity, high-flow area of ​​air through the outer annular region of the refractory structure, direct the low-velocity, low-flow area of ​​air through the inner annular region of the refractory structure, and direct the medium-velocity, medium-flow area of ​​air through the middle region of the refractory structure. Furthermore, the inner annular region of the refractory structure may not have any airflow passing through it.

[0149] When the burn-resistant structure burns, the regional airflow with a large flow rate will pass through the outer ring area of ​​the burn-resistant structure, which originally has a relatively high heat dissipation efficiency, at a high speed, taking away a large amount of combustion heat more quickly, and further increasing the rate of heat loss from combustion. The regional airflow with a medium flow rate will pass through the middle area of ​​the burn-resistant structure at a high speed. Compared with the existing flame arrester with a large flow of pressure relief airflow passing through the middle area of ​​the burn-resistant structure, it can effectively solve the problem of local heat concentration in the middle area of ​​the burn-resistant structure, and effectively reduce the risk of tempering and burn-through of the middle area. In addition, the regional airflow with a low flow rate will pass through the inner ring area of ​​the burn-resistant structure at a low speed, or there will be no regional airflow passing through the inner ring area of ​​the burn-resistant structure, which is equivalent to forming the inner ring area of ​​the burn-resistant structure into a low thermal conductivity area between the outer ring area and the middle area, thereby weakening the transfer of combustion heat from the outer ring area of ​​the burn-resistant structure to the middle area, and further reducing the risk of tempering and burn-through in the middle area of ​​the burn-resistant structure.

[0150] In a specific embodiment, the average velocity of the airflow in the area with high flow rate and large flow is defined as v1 and the flow area is defined as s1, the average velocity of the airflow in the area with low flow rate and low flow is defined as v2 and the flow area is defined as s2, the average velocity of the airflow in the area with medium flow rate and medium flow is defined as v3 and the flow area is defined as s3, and the average flow velocity of the pressure relief airflow flowing into the pressure relief air inlet end 11 is defined as v and the flow area is defined as s.

[0151] At this time, the porosity distribution of the cavity guide structure, the air inlet end guide structure or the burn-resistant structure can be adjusted in terms of structure and parameters to satisfy the following relationship:

[0152] v1 ≥ 1.2v, preferably v1 ≥ 1.5v;

[0153] v3≤0.8v, preferably v3≤0.5v;

[0154] v2≤0.4v, preferably v2≤0.2v;

[0155] v1*s1≥0.5v*s, preferably v1*s1≥0.7v*s;

[0156] v3*s3≤0.5v*s, preferably v3*s3≤0.3v*s;

[0157] v2*s2≤0.3v*s, preferably v2*s2≤0.1v*s.

[0158] For the cavity guide structure (airflow control method 1):

[0159] Referring to Figure 11, when the cavity guide structure divides the cavity 13 into an outer area airflow G11 and an inner area airflow G12, the flow velocity of the outer area airflow G11 can be greater than the flow velocity of the inner area airflow G12, and / or the flow rate of the outer area airflow G11 can be greater than the flow rate of the inner area airflow G12, so as to satisfy the aforementioned first flow velocity and flow distribution form.

[0160] Referring to Figure 12, when the cavity guide structure divides the cavity 13 into an outer ring area airflow G21, an inner ring area airflow G22, and a middle area airflow G23, the flow velocity of the outer ring area airflow G21, the flow velocity of the middle area airflow G23, and the flow velocity of the inner ring area airflow G22 can be distributed from large to small, and / or the flow rate of the outer ring area airflow G21, the flow rate of the middle area airflow G23, and the flow rate of the inner ring area airflow G22 can be distributed from large to small to meet the aforementioned second flow velocity and flow distribution form.

[0161] It should be noted that a series of parameters such as the radius of the middle guide member 4, the first annular guide member 5, and the second annular guide member 6 of the cavity guide structure, the spacing along the upstream and downstream directions, and the spacing between the inner wall of the cavity 13 can be adjusted to meet the actual required flow rate distribution.

[0162] For the air intake guide structure (air flow control method 2):

[0163] 15 , when the air inlet end guide structure divides the pressure relief air inlet end 11 into an outer airflow region G31 and an inner airflow region G32, the flow velocity of the outer airflow region G31 can be greater than the flow velocity of the inner airflow region G32, and / or the flow rate of the outer airflow region G31 can be greater than the flow rate of the inner airflow region G32, so as to satisfy the first flow velocity and flow rate distribution form described above.

[0164] For example, the flow area at the inlet end of the annular region between the inner peripheral wall of the pressure relief air inlet end 11 and the first annular partition 7 can be made larger than the flow area at the inlet end of the inner region of the first annular partition 7, so that the flow rate of the airflow G31 in the outer region is greater than the flow rate of the airflow G32 in the inner region.

[0165] In addition, the outlet flow area of ​​the annular area between the inner circumferential wall of the pressure relief inlet end 11 and the first annular partition 7 can be made smaller than the outlet flow area of ​​the inner area of ​​the first annular partition 7, so as to achieve a flow rate of the airflow G31 in the outer area greater than the flow rate of the airflow G32 in the inner area.

[0166] 16 , when the air inlet end guide structure divides the pressure relief air inlet end 11 into an outer layer airflow area G31, an inner layer airflow area G321, and an intermediate layer airflow area G322, the flow velocity of the outer layer airflow area G31, the flow velocity of the intermediate layer airflow area G322, and the flow velocity of the inner layer airflow area G321 can be distributed from large to small, and / or the flow rate of the outer layer airflow area G31, the flow rate of the intermediate layer airflow area G322, and the flow rate of the inner layer airflow area G321 can be distributed from large to small, so as to meet the second flow velocity and flow rate distribution form described above;

[0167] For example, the split ratio at the inlet end of the annular area between the inner peripheral wall of the pressure relief air inlet end 11 and the first annular partition 7 can be a, the split ratio at the inlet end of the annular area between the first annular partition 7 and the second annular partition 8 can be b, and the split ratio at the inlet end of the inner area of ​​the second annular partition 8 can be c, satisfying: a>c>b, so as to achieve the flow rate of the airflow G31 in the outer layer area, the flow rate of the airflow G322 in the middle area, and the flow rate of the airflow G321 in the inner layer area distributed from large to small;

[0168] In addition, the outlet flow area of ​​the annular area between the inner circumferential wall of the pressure relief inlet end 11 and the first annular baffle 7, the outlet flow area of ​​the inner area of ​​the second annular baffle 8, and the outlet flow area of ​​the annular area between the first annular baffle 7 and the second annular baffle 8 can be set from small to large to achieve the flow rate of the airflow G31 in the outer layer area, the flow rate of the airflow G322 in the middle area, and the flow rate of the airflow G321 in the inner layer area distributed from large to small.

[0169] For the porosity distribution of the burn-resistant structure (airflow control method three):

[0170] Referring to Figure 22, when the burn-resistant structure is provided with an outer ring area 22a of the burn-resistant layer and an inner zone of the burn-resistant layer located inside the outer ring area 22a of the burn-resistant layer, the porosity of the outer ring area 22a of the burn-resistant layer can be made greater than the porosity of the inner zone of the burn-resistant layer to satisfy the aforementioned first flow velocity distribution form.

[0171] Referring to Figure 24, when the burn-resistant structure is provided with a burn-resistant layer outer ring zone 22a, a burn-resistant layer inner ring zone 22b, and a burn-resistant layer middle zone 22c arranged in sequence from the outside to the inside, the porosity of the burn-resistant layer outer ring zone 22a, the porosity of the burn-resistant layer middle zone 22c, and the porosity of the burn-resistant layer inner ring zone 22b can be set from large to small to meet the aforementioned second flow rate distribution form.

[0172] Porosity must primarily meet fire-retardant and burn-resistant requirements while also taking into account flow performance requirements. Furthermore, the porosity design must be able to alter the flow field distribution. For fire-retardant requirements, porosity requirements vary for different combustible gases. It should be noted that the porosity of the middle region 22c of the burn-resistant layer must be lower than the minimum porosity of the outer annular region 22a of the burn-resistant layer.

[0173] Multi-layer fire-resistant structure

[0174] 1 and 2 , the burn-resistant structure may include a plurality of burn-resistant layers 2 sequentially spaced apart in the axial direction of the pressure relief exhaust port 12. The burn-resistant layer 2 located most downstream is formed as a combustion-side burn-resistant layer 21 a, and the burn-resistant layer 2 located upstream of the combustion-side burn-resistant layer 21 a is formed as a protection-side burn-resistant layer 21 b.

[0175] When the combustible pressure relief airflow is continuously discharged through the pressure relief exhaust end 12 and is ignited on the downstream side of the combustion side burn-resistant layer 21a, the combustion side burn-resistant layer 21a will be burned for a long time. At this time, since at least one protective side burn-resistant layer 21b is provided upstream of the combustion side burn-resistant layer 21a, the heat dissipation area of ​​the combustion heat can be greatly increased, and the risk of the combustion side burn-resistant layer 21a being burned through due to heat accumulation can be effectively reduced. Even if the combustion side burn-resistant layer 21a is burned through, the protective side burn-resistant layer 21b can take over and play a fire-retardant role, thereby greatly extending the fire-retardant time of the burn-resistant structure.

[0176] In a specific embodiment, the protective side burn-resistant layer 21b closest to the combustion side burn-resistant layer 21a is defined as the first protective side burn-resistant layer, the distance between the combustion side burn-resistant layer 21a and the first protective side burn-resistant layer is L, the diameter of the first protective side burn-resistant layer is D2, and L is related to D2 and the fire resistance level (the fire resistance level is expressed by the MESG value of the representative gas).

[0177] It should be noted that the spacing L has a significant impact on the fire-retardant and burn-resistant performance. When the spacing L is small, since the heat transferred by the combustion-side resistant layer 21a is mainly heat conduction and heat radiation, the heat transfer will increase exponentially. The increase in heat will cause the temperature of the first protective side resistant layer to rise rapidly, increasing the risk of fire-retardant failure. When the spacing L is large, after a long period of combustion, the temperature on the upstream side of the combustion-side resistant layer 21a is high, which can easily ignite the combustible gas in the gap between the combustion-side resistant layer 21a and the first protective side resistant layer. The combustible gas in a larger gap or continuous combustion can easily cause smoldering. The combustion heat in the gap is more difficult to dissipate outward, and most of it is transferred upstream, also increasing the risk of fire-retardant failure.

[0178] Therefore, to achieve a better fire-retardant effect, L can be limited to prevent it from being too large. This reduces the risk of the high-temperature refractory layer directly igniting the decompressed airflow in the area between the combustion-side refractory layer 21a and the first protective-side refractory layer, leading to interlayer smoldering, thereby reducing the risk of fire-retardant failure. Furthermore, L can be prevented from being too small, thereby preventing increased thermal conductivity between the combustion-side refractory layer 21a and the first protective-side refractory layer.

[0179] In a specific embodiment, the flow area of ​​each burning-resistant layer 2 is not less than the flow area of ​​the pressure relief air inlet end 11 .

[0180] Axial insulation of burn-resistant structure (insulation support structure)

[0181] 1 and 2 , the fire-blocking structure may include a heat-insulating support structure 3 disposed between two adjacent fire-resistant layers 2 , wherein the heat-insulating support structure 3 is in contact with the two adjacent fire-resistant layers 2 .

[0182] The thermal insulation support structure 3 has a thermal insulation function, which can effectively weaken the heat radiation and heat conduction between the two adjacent burn-resistant layers 2, thereby reducing and delaying the transfer of combustion heat to the inside of the shell 1; at the same time, the thermal insulation support structure 3 also has a supporting function. When the downstream burn-resistant layer 2 is deformed by heat, it can support the deformed burn-resistant layer 2 to avoid direct contact with the upstream burn-resistant layer 2 too quickly, thereby slowing down the transfer of combustion heat to the inside of the shell 1, and taking into account the overall structural integrity of the burn-resistant structure.

[0183] To improve support strength, the thermal insulation support structure 3 can be configured to provide support throughout the entire radial range of the burn-resistant layer 2, thereby effectively preventing deformation and collapse of the downstream burn-resistant layer 2 after prolonged combustion. For example, referring to Figure 18 , a triangular thermal insulation support structure 3 can be used, with the diameter of the circumscribed circle of the triangle equal to the diameter of the burn-resistant layer 2. Alternatively, referring to Figure 17 , a cross-shaped thermal insulation support structure 3 can be used, with the lengths of the two straight line segments forming the cross equal to the diameter of the burn-resistant layer 2.

[0184] In order to improve the thermal insulation effect, the total contact area between the thermal insulation support structure 3 and two adjacent fire-resistant layers 2 should be as small as possible.

[0185] In a specific embodiment, the thermal insulation support structure 3 forms point contact with the burn-resistant layer 2. For example, the thermal insulation support structure 3 may be in contact with the burn-resistant layer 2 by providing a convex structure.

[0186] In a specific embodiment, the heat-insulating support structure 3 forms a line contact with the burn-resistant layer 2 . For example, a slender cylindrical heat-insulating support structure 3 may be used.

[0187] In a specific embodiment, the heat-insulating support structure 3 forms surface contact with the burn-resistant layer 2 . For example, a slender rectangular heat-insulating support structure 3 may be used.

[0188] In order to improve the thermal insulation effect, it can also be achieved by increasing the thickness of the thermal insulation support structure 3.

[0189] In a specific embodiment, the thermal insulation support structure 3 is a multi-layer thermal insulation support structure. For example, referring to Figures 19 and 20, the multi-layer thermal insulation support structure may include a plurality of thermal insulation support units 31 stacked in sequence along the axial direction, i.e., the total thickness of the thermal insulation support structure 3 is increased by stacking a plurality of independent thermal insulation support units 31; or, referring to Figure 21, the multi-layer thermal insulation support structure may also include a thermal insulation support body 32a and a thermal insulation support protrusion 32b protruding axially from the thermal insulation support body 32a, i.e., the total thickness of the thermal insulation support structure 3 is increased by providing a heightened structure (thermal insulation support protrusion 32b) in the integrated thermal insulation support structure 3.

[0190] In addition, the thermal insulation support structure 3 should be made of high temperature resistant material to ensure that when the fire-resistant structure burns for a long time and continuously transfers heat to the thermal insulation support structure 3, the thermal insulation support structure 3 will not deform or deform excessively and lose its good supporting strength.

[0191] In a specific embodiment, the heat-resistant temperature of the thermal insulation support structure 3 is not less than 1000°C.

[0192] In a specific embodiment, the linear variation rate of the thermal insulation support structure 3 is no more than 10%. Preferably, the linear variation rate of the thermal insulation support structure 3 is no more than 5%, so that the thermal insulation support structure 3 can be heated for a long time without obvious deformation.

[0193] Furthermore, the present invention does not limit the internal structure of the thermal insulation support structure 3. For example, the thermal insulation support structure 3 can be a solid thermal insulation support structure, a porous thermal insulation support structure with a porous structure, or a hollow thermal insulation support structure with a hollow cavity.

[0194] Radial insulation of fire-resistant structure

[0195] Based on the content in the embodiment of the aforementioned airflow control method three, it is obvious that when the burn-resistant structure is provided with one or more burn-resistant layers 2, a single burn-resistant layer 2 can be divided into a burn-resistant layer outer ring area 22a and a burn-resistant layer inner area located on the inner side of the burn-resistant layer outer ring area 22a with reference to Figure 22; or, a single burn-resistant layer 2 can be divided into a burn-resistant layer outer ring area 22a, a burn-resistant layer inner ring area 22b and a burn-resistant layer middle area 22c arranged in sequence from the outside to the inside with reference to Figure 24.

[0196] Referring to Figure 22, when the burn-resistant layer 2 is provided with an outer ring area 22a of the burn-resistant layer and an inner area of ​​the burn-resistant layer, the porosity of the inner area of ​​the burn-resistant layer can be zero, thereby the inner area of ​​the burn-resistant layer can be set as a closed insulation area, while the outer ring area 22a of the burn-resistant layer can be used for pressure relief airflow.

[0197] Because the inner area of ​​the refractory layer is closed and insulated, the pressure relief airflow cannot flow directly through this inner area to the downstream inner area of ​​the refractory layer 2, thereby reducing the generation of combustion heat in this downstream inner area. Furthermore, the inner area of ​​the refractory layer effectively slows the transfer of combustion heat from the outer annular area 22a of the refractory layer to the inner side. Therefore, a large amount of combustion heat can be quickly dissipated outward from the outer annular area 22a of the refractory layer, effectively extending the fire arrest duration.

[0198] In a specific embodiment, referring to Figure 23 , the burn-resistant layer 2 may include a first closed heat-insulating disk 23a and a plurality of first fire-retardant disks 23b. The outer annular region 22a and the inner region of the burn-resistant layer are both disposed on the first closed heat-insulating disk 23a. The outer annular region 22a of the burn-resistant layer of the first closed heat-insulating disk 23a is provided with a plurality of first mounting openings spaced circumferentially therefrom. The plurality of first fire-retardant disks 23b are mounted in the plurality of first mounting openings in a one-to-one correspondence.

[0199] With such an arrangement, multiple first fire-blocking discs 23b can provide pressure relief airflow for circulation, thereby ensuring the flowability of the outer ring area 22a of the burn-resistant layer. Except for the area in which multiple first fire-blocking discs 23b are embedded, the remaining areas of the first closed heat-insulating disc 23a cannot provide pressure relief airflow for circulation. At the same time, it has a heat insulation function, which can not only effectively slow down the transfer of combustion heat from the outer ring area 22a of the burn-resistant layer to the inside, but also slow down the mutual heat transfer between multiple first fire-blocking discs 23b, so that the combustion heat is dissipated to the outside atmosphere in greater quantities.

[0200] Referring to Figure 24, when the burn-resistant layer 2 is provided with a burn-resistant layer outer ring area 22a, a burn-resistant layer inner ring area 22b and a burn-resistant layer middle area 22c, the porosity of the burn-resistant layer inner ring area 22b can be zero, thereby the burn-resistant layer inner ring area 22b can be set as a closed heat-insulating area, while the burn-resistant layer outer ring area 22a and the burn-resistant layer middle area 22c can both provide pressure relief airflow.

[0201] The above arrangement takes into account the circulation efficiency of the pressure relief airflow and preserves the flowability of the middle area 22c of the burn-resistant layer. At the same time, the inner annular area 22b of the burn-resistant layer is closed and has a heat-insulating function, which can effectively slow the transfer of combustion heat from the outer annular area 22a of the burn-resistant layer to the middle area 22c of the burn-resistant layer, thereby preventing the accumulation of large amounts of combustion heat in the middle area 22c of the burn-resistant layer from causing flashback and burn-through. The large amount of combustion heat can be quickly dissipated outward from the outer annular area 22a of the burn-resistant layer, thereby effectively extending the fire-retardant duration.

[0202] In a specific embodiment, referring to Figure 26 , the burn-resistant layer 2 may include a second closed heat-insulating disk 24a, a plurality of second fire-retardant disks 24b, and a single third fire-retardant disk 24c. The outer ring region 22a, the inner ring region 22b, and the middle region 22c of the burn-resistant layer are all disposed on the second closed heat-insulating disk 24a. The outer ring region 22a of the burn-resistant layer of the second closed heat-insulating disk 24a is provided with a plurality of second mounting openings spaced circumferentially therefrom. The plurality of second fire-retardant disks 24b are mounted in the plurality of second mounting openings in a one-to-one correspondence. The middle region 22c of the burn-resistant layer of the second closed heat-insulating disk 24a is provided with a third mounting opening, and the third fire-retardant disk 24c is mounted in the third mounting opening.

[0203] With this arrangement, the third fire-blocking disc 24c and the plurality of second fire-blocking discs 24b are both capable of allowing pressure relief airflow to circulate, thereby ensuring flowability in the middle region 22c and the outer annular region 22a of the burn-resistant layer. However, the second closed heat-insulating disc 24a, except for the area where the third fire-blocking disc 24c and the plurality of second fire-blocking discs 24b are embedded, is unable to allow pressure relief airflow to circulate. Furthermore, the second closed heat-insulating disc 24a also provides a heat-insulating function, effectively slowing the transfer of combustion heat from the outer annular region 22a of the burn-resistant layer to the middle region 22c of the burn-resistant layer. It also slows down heat transfer between the plurality of second fire-blocking discs 24b, allowing a greater amount of combustion heat to be dissipated into the atmosphere.

[0204] In a specific embodiment, referring to Figure 25 , the burn-resistant layer 2 may include a fire-blocking ring 25a, a closed heat-insulating ring 25b, and a fourth fire-blocking disk 25c, which are nested in sequence from the outside in. The outer ring region 22a of the burn-resistant layer is disposed on the fire-blocking ring 25a, the inner ring region 22b of the burn-resistant layer is disposed on the closed heat-insulating ring 25b, and the middle region 22c of the burn-resistant layer is disposed on the fourth fire-blocking disk 25c.

[0205] With this arrangement, both the fire arrester ring 25a and the fourth fire arrester disk 25c allow for the flow of pressure relief air, thereby ensuring the flow of air between the outer ring area 22a and the middle area 22c of the refractory layer. The closed heat-insulating ring 25b, however, does not allow for the flow of pressure relief air and also provides a heat-insulating function, effectively slowing the transfer of combustion heat from the outer ring area 22a of the refractory layer to the middle area 22c, allowing a greater amount of combustion heat to be dissipated into the atmosphere.

[0206] It should be noted that the above-mentioned first closed insulation disk 23a, second closed insulation disk 24a, closed insulation ring 25b or other forms of closed insulation structures should use low thermal conductivity materials. The interior of these closed insulation structures can be set as a hollow structure, for example. In the hollow state, it can be vacuumed or filled with low thermal conductivity materials to achieve good insulation performance.

[0207] Accumulated porous fire-resistant layer

[0208] The fire-resistant layer 2 can be a corrugated plate fire-resistant disk with a porous structure, a sintered porous fire-resistant layer, a stacked porous fire-resistant layer, etc. In this embodiment, some specific embodiments are provided for the stacked porous fire-resistant layer to achieve a better fire-retardant time extension effect.

[0209] In a specific embodiment, referring to FIG. 27 , the stacked porous burning-resistant layer may include a first shell 26 a and a plurality of stacked particles 26 b stacked in the first shell 26 a .

[0210] Both the first shell 26a and the accumulated particles 26b are resistant to high temperatures. Numerous interparticle gaps are formed between the multiple accumulated particles 26b, creating a porous structure that provides a certain degree of flow. Furthermore, both the upstream and downstream sidewalls of the first shell 26a are provided with multiple first shell through-holes. The pressure relief airflow can flow through the multiple first shell through-holes in the upstream sidewall into the burn-resistant layer, then flow through the multiple interparticle gaps to the downstream sidewall, and finally exit the burn-resistant layer through the multiple first shell through-holes in the downstream sidewall. To ensure that the accumulated particles 26b do not fall out of the first shell through-holes, the diameter of the first shell through-holes should be smaller than that of the accumulated particles 26b.

[0211] It should be noted that the thermal expansion of the multiple accumulated particles 26b may cause the interparticle spaces in certain areas to expand excessively. This excessive increase in the airflow flowing through the interparticle spaces in these areas can easily cause flashback and lead to flame arrester failure. Therefore, thermal deformation of the accumulated particles 26b should be minimized.

[0212] For example, the spacing between the upstream inner wall and the downstream inner wall of the first shell 26a can be made the same as the total stacking thickness of the multiple stacked particles 26b along the axial direction of the stacked porous fire-resistant layer, so as to compact the multiple stacked particles 26b, which can effectively reduce the thermal expansion amplitude of the multiple stacked particles 26b and avoid excessive expansion of the particle gap, thereby effectively reducing the probability of fire-blocking failure.

[0213] In addition, the diameter d1 of the stacked particles 26b and the total stacking thickness T3 of multiple stacked particles 26b along the axial direction of the stacked porous fire-resistant layer are related to the gas explosion level. In order to achieve a better fire-retardant time extension effect, d1 and T3 can be optimized.

[0214] For the stacked porous fire-resistant layer, the pressure relief airflow needs to pass through the particle stacking gap. When the particle size of the stacked particles 26b is larger, the particle stacking gap is also larger. An excessively large particle stacking gap will cause the flame to burn in the gap, thereby causing backfire and leading to fire-blocking failure.

[0215] By optimizing the design of d1 and T3, the flame can be quenched between the pores, thereby achieving fire resistance while ensuring flow performance.

[0216] In a specific embodiment, the stacked porous burning-resistant layer may include a second shell and a plurality of lightweight spheres stacked in the second shell.

[0217] Both the second shell and the lightweight spheres are heat-resistant. Multiple gaps between the spheres form a porous structure, resulting in a certain degree of fluidity. Furthermore, both the upstream and downstream sidewalls of the second shell are provided with multiple second shell through-holes. The pressure-relief airflow can flow through the multiple second shell through-holes on the upstream sidewall into the burn-resistant layer, then flow through the multiple gaps between the spheres to the downstream sidewall, and finally out of the burn-resistant layer through the multiple second shell through-holes on the downstream sidewall. To ensure that the lightweight spheres do not fall out of the second shell through-holes, the diameter of the second shell through-holes should be smaller than that of the lightweight spheres.

[0218] In particular, due to the small mass of the lightweight spheres, the pressure relief airflow can drive multiple lightweight spheres to rotate when passing through multiple gaps between the spheres, realizing the hot and cold cycle of the lightweight spheres, extending the heat transfer time, and helping to improve the fire retardant performance.

[0219] Convex design of the burning-resistant layer on the combustion side

[0220] By setting at least part of the downstream side surface of the combustion side fire-resistant layer 21a to protrude toward the downstream, the downstream side surface area of ​​the combustion side fire-resistant layer 21a is expanded, which can enhance the heat dissipation effect of the downstream side and effectively improve the problem of combustion heat accumulation, thereby extending the fire-retardant time of the combustion side fire-resistant layer 21a.

[0221] For example, the downstream side surface of the combustion side resistant layer 21a can be set as a resistant layer curved surface, which has at least one protruding position and can be a variable curvature curved surface, a constant curvature curved surface, and other different specific forms; when using a constant curvature curved surface with a single protruding position, the resistant layer curved surface is a partial spherical surface (that is, a part of a complete spherical surface), which can take into account both improving the heat dissipation effect and simplifying processing, which is conducive to reducing production costs.

[0222] In other words, this embodiment does not limit the specific shape of the protruding area on the downstream side of the combustion-side burn-resistant layer 21 a, as long as it is conducive to improving the heat dissipation effect.

[0223] In one specific embodiment, referring to FIG. 28 , the combustion-side burn-resistant layer 21a includes a burn-resistant layer disc portion 27a and a burn-resistant layer convex portion 27b connected to the downstream side of the burn-resistant layer disc portion 27a. The downstream side surface of the burn-resistant layer convex portion 27b is configured as a partial spherical surface that protrudes toward the downstream. Thus, in the downstream portion of the combustion-side burn-resistant layer 21a, the burn-resistant layer convex portion 27b can enhance heat dissipation. In the upstream portion of the combustion-side burn-resistant layer 21a, the burn-resistant layer disc portion 27a has the same shape as the protective-side burn-resistant layer 21b. Both the upstream side surface of the burn-resistant layer disc portion 27a and the downstream side surface of the protective-side burn-resistant layer 21b are flat surfaces. This ensures that the spacing between the upstream side surface of the burn-resistant layer disc portion 27a and the downstream side surface of the protective-side burn-resistant layer 21b is uniform throughout the radial range, thereby avoiding increased heat conduction due to an excessively small spacing in a local area or smoldering due to an excessively large spacing.

[0224] In addition, the curvature corresponding to the local sphere is β, which is related to the structural size and fire resistance grade of the combustion-side fire-resistant layer 21a.

[0225] High temperature resistant coating

[0226] In order to improve the fire-resistant and burning-resistant performance, a high-temperature resistant coating can be coated on at least the downstream side of the burning-resistant layer 2 itself. Preferably, a high-temperature resistant coating that does not deteriorate in performance under long-term combustion conditions of not less than 2 hours and above 450°C is coated.

[0227] In a specific embodiment, the high-temperature resistant coating is arranged to cover the outer surface of the burn-resistant layer 2, including the entire surface composed of the downstream side, upstream side, peripheral wall surface, hole or gap surface of the burn-resistant layer 2 itself, so as to improve the fire-resistant and burn-resistant performance of the burn-resistant layer 2 over a larger area.

[0228] In a specific embodiment, the combustion-side burn-resistant layer 21a is preferably coated with a high-temperature resistant coating having high thermal emissivity or high reflectivity.

[0229] In a specific embodiment, the protection-side fire-resistant layer 21 b is preferably coated with a high-temperature resistant coating having low thermal conductivity.

[0230] In a specific embodiment, the thickness of the high temperature resistant coating is T t At this time, the characteristic value of the fire-resistant gap of the burning-resistant layer 2 is h g , the thickness of the refractory layer 2 is T0.

[0231] It should be noted that the characteristic value of the fire-resistant gap h of the fire-resistant layer 2 is g It is closely related to the fire resistance and burning resistance. When the characteristic value of the fire resistance gap h gWhen it is larger, the flow rate of the pressure relief airflow is larger, and the combustion heat is high, so that more heat per unit area is transferred to the downstream resistant layer 2, thereby affecting the fire retardant effect; and when the characteristic value of the fire retardant gap h g When it is small, although the flow rate of the pressure relief air flow that can flow is small and its combustion heat is low, the circulation performance is poor. Therefore, in order to obtain better circulation performance in practical applications, a larger area of ​​the burn-resistant layer is required. However, as the area of ​​the burn-resistant layer increases, the total combustion heat does not decrease. The heat in the middle area of ​​the burn-resistant layer will be more difficult to dissipate due to the increase in the area of ​​the burn-resistant layer, thereby affecting the fire-retardant and burn-resistant performance.

[0232] In the case of high temperature resistant coating, the characteristic value of the fire retardant gap of the burning resistant layer 2 is h g changes, so preferably, the characteristic value of the fire-blocking gap can be h g And the characteristic value of the fire-blocking gap h g Thickness T of high temperature resistant coating t Make a limitation.

[0233] Long-term fire retardant conditions of not less than 2 hours

[0234] Currently, some domestic storage tanks or tank farms struggle to meet nitrogen blanketing requirements, resulting in a Zone 1 vapor phase. API 2000 recommends that for tanks with a Zone 1 vapor phase after nitrogen blanketing (or other gas sealing), the flame arrester or flame-blocking breather valve on the tank should be a long-lasting atmospheric deflagration-type flame arrester with a flame-blocking duration of at least two hours. However, existing flame arresters or flame-blocking breather valves struggle to meet the required minimum flame-blocking duration of two hours.

[0235] Based on the above concept, the present invention further provides multiple embodiments of fire-retardant structures with a fire-retardant time of not less than 2 hours, and sets up multiple comparative examples for comparison to better reflect the improvement effect of the present invention on the fire-retardant time.

[0236] In the experimental tests of multiple embodiments and comparative examples, the diameter of the pressure relief inlet port 11 was DN100. The test medium used a mixture of n-hexane and air as recommended by ISO 16852, with a volume fraction of n-hexane in the mixture of 2.1%. Furthermore, the experimental tests focused on the temperature changes on the upstream and downstream sides of the fire-resistant structure, the time required for the upstream side to rise by 20°C, and whether the fire could be prevented after burning for two hours.

[0237] Example 1:

[0238] Referring to Figures 8 and 18, the specific structural parameters of the fire-blocking structure are as follows:

[0239] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0240] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0241] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0242] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0243] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0244] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0245] Example 2:

[0246] Referring to Figures 4, 5 and 18, the specific structural parameters of the fire-blocking structure are as follows:

[0247] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0248] The central flow guide 4 is a curved metal circular plate with a plurality of through-holes disposed within its central circular region. The maximum span of the curved metal circular plate along the radial direction of the pressure relief inlet port 11 is equal to the diameter d of the pressure relief inlet port 11. Furthermore, the upstreammost end of the curved metal circular plate is spaced 0.25d from the upstream sidewall of the cavity 13. Furthermore, the boundary diameter of the central circular region of the central flow guide 4 is 0.5d, and the total flow area of ​​all through-holes is half the total area of ​​the central circular region.

[0249] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0250] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0251] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0252] Example 3:

[0253] Referring to Figures 10 and 18, the specific structural parameters of the fire-blocking structure are as follows:

[0254] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0255] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0256] The first annular flow guide 5 is a metal annular plate with inner and outer diameters d and 1.4d respectively, and is axially spaced 0.15d from the middle flow guide 4;

[0257] The second annular flow guide 6 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.15d from the first annular flow guide 5;

[0258] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0259] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0260] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0261] Example 4:

[0262] Referring to Figures 24 and 18, the specific structural parameters of the fire-blocking structure are as follows:

[0263] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0264] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0265] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0266] The protective-side fire-resistant layer 21b comprises a corrugated plate fire-blocking disc, a closed heat-insulating metal ring, and a corrugated plate fire-blocking ring, which are sequentially sleeved from the inside out. The closed heat-insulating metal ring has a hollow cavity or a cavity filled with a low-thermal-conductivity material. The corrugated plate fire-blocking disc has a diameter of 0.8d, a thickness of 15mm, and a fire-blocking gap of 0.45mm. The corrugated plate fire-blocking ring has inner and outer diameters of 1.3d and 1.6d, respectively, a thickness of 15mm, and a fire-blocking gap of 0.45mm.

[0267] The combustion-side burn-resistant layer 21a comprises a corrugated plate fire-stop disk, a closed heat-insulating metal ring, and a corrugated plate fire-stop ring, which are sequentially sleeved from the inside out. The closed heat-insulating metal ring has a hollow cavity or a cavity filled with a low-thermal-conductivity material. The corrugated plate fire-stop disk has a diameter of 0.8d, a thickness of 15mm, and a fire-stop gap of 0.45mm. The corrugated plate fire-stop ring has an inner and outer diameter of 1.3d and 1.6d, respectively, a thickness of 15mm, and a fire-stop gap of 0.45mm.

[0268] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0269] Example 5:

[0270] Referring to Figures 9 and 18, the specific structural parameters of the fire-blocking structure are as follows:

[0271] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0272] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0273] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0274] The two protective side fire-resistant layers 21b are both made of corrugated plate fire-retardant disks, each with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0275] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0276] The two heat-insulating support structures 3 are both made of high-temperature resistant metal wires, and their cross-sectional diameters are both 2 mm. The two heat-insulating support structures 3 are both arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0277] Example 6:

[0278] Referring to Figures 8 and 19, the specific structural parameters of the fire-blocking structure are as follows:

[0279] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0280] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0281] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0282] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0283] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0284] The heat-insulating support structure 3 uses a double layer of high-temperature resistant metal wires. The cross-sectional diameter of each layer of high-temperature resistant metal wires is 2 mm and they are all arranged into a triangle. The diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21a.

[0285] Example 7:

[0286] Referring to Figures 8 and 21, the specific structural parameters of the fire-blocking structure are as follows:

[0287] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0288] The middle guide member 4 is a metal circular plate with a diameter of 0.8d and a distance of 0.25d from the upstream side wall of the cavity 13;

[0289] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0290] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0291] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0292] The thermal insulation support structure 3 uses a high-temperature resistant metal wire with a thermal insulation support body 32a and a thermal insulation support protrusion 32b. The cross-sectional diameter of the thermal insulation support body 32a is 2mm, the thickness of the thermal insulation support protrusion 32b protruding from the thermal insulation support body 32a is 1mm, and the thermal insulation support protrusion 32b is a hemispherical structure.

[0293] Example 8:

[0294] 6 and 18, the fire-blocking structure can be applied as a call valve, and its specific structural parameters are as follows:

[0295] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0296] A first flange is provided at the upstream end of the pressure relief air inlet end 11;

[0297] The central guide member 4 serves as a pressure relief valve disc 43 of the call valve. The pressure relief valve disc 43 is connected to a first guide rod, which can slide in the upstream and downstream directions within the first guide groove. The pressure relief valve disc 43 can switch the on-off state between the cavity 13 and the pressure relief inlet end 11. When the pressure relief valve disc 43 moves downstream to open, thereby connecting the cavity 13 with the pressure relief inlet end 11, the pressure relief valve disc 43 plays a guiding and diverting role. The diameter of the pressure relief valve disc 43 is d, and the distance between it and the upstream side wall of the cavity 13 is 0.25d.

[0298] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0299] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0300] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0301] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0302] Example 9:

[0303] Referring to Figures 7 and 18, the fire-blocking structure can be applied to the breathing valve, and its specific structural parameters are as follows:

[0304] The cavity 13 is a coaxial cavity with equal diameter. The diameter of the cavity 13 is D, the diameter of the pressure relief air inlet end 11 is d, and D=2d.

[0305] A second flange is provided at the upstream end of the pressure relief air inlet end 11;

[0306] The middle guide member 4 serves as a pressure relief valve disc 43 of the breathing valve. The pressure relief valve disc 43 is connected to the second guide rod, which can slide in the upstream and downstream directions within the second guide groove. The pressure relief valve disc 43 can switch the on-off state between the cavity 13 and the pressure relief air inlet end 11. When the pressure relief valve disc 43 moves downstream to open and connect the cavity 13 with the pressure relief air inlet end 11, the pressure relief valve disc 43 plays a guiding and diverting role. The diameter of the pressure relief valve disc 43 is d, and it is separated from the upstream side wall of the cavity 13 by 0.25d.

[0307] The first annular flow guide 5 is a metal annular plate with inner and outer diameters of 1.3d and 1.6d respectively, and is axially spaced 0.25d from the middle flow guide 4;

[0308] The fire-resistant layer 21b on the protection side is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0309] The combustion side fire-resistant layer 21a is made of a corrugated plate fire-retardant disk with a diameter of 2d, a thickness of 15mm, and a fire-retardant gap value of 0.45mm;

[0310] The heat-insulating support structure 3 is made of high-temperature resistant metal wire with a cross-sectional diameter of 2 mm. The heat-insulating support structure 3 is arranged in a triangle shape, and the diameter of the circumscribed circle of the triangle is equal to the diameter of the combustion-side resistant layer 21 a.

[0311] Comparative Example 1:

[0312] 29 , the fire-blocking structure in the figure can be regarded as a simplified and adjusted structure based on the fire-blocking structure provided in Example 1. Except for the differences specifically described below, the structural parameters of the common structure in Comparative Example 1 are consistent with those in Example 1.

[0313] The difference between Comparative Example 1 and Example 1 is that the fire-blocking structure in Comparative Example 1 is not provided with a heat-insulating support structure 3, a central flow guide 4 and a first annular flow guide 5, and no spacing is left between the combustion side burn-resistant layer 21a and the protection side burn-resistant layer 21b.

[0314] Comparative Example 2:

[0315] Continuing with Figure 29 as an example, the only difference between Comparative Example 2 and Comparative Example 1 is that the fire-retardant gap values ​​of the combustion side burn-resistant layer 21a and the protection side burn-resistant layer 21b in Comparative Example 1 are both 0.45 mm, while the fire-retardant gap values ​​of the combustion side burn-resistant layer 21a and the protection side burn-resistant layer 21b in Comparative Example 2 are both 0.85 mm.

[0316] The following table compares the experimental data of Examples 1-9 and Comparative Examples 1-2:

[0317] As can be seen from the above table, the fire-retardant structure of the present invention, when provided with a multi-layered burn-resistant structure, a heat-insulating support structure 3 and the active diversion technology, has been experimentally proven to achieve a fire-retardant and burn-resistant time of not less than 2 hours, and the fire-retardant effect is significantly improved compared to the existing technology.

[0318] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0319] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0320] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0321] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A fire-blocking structure, characterized in that: The fire-blocking structure comprises: A housing (1) is provided with a pressure relief air inlet end (11), a pressure relief air outlet end (12), and a cavity (13) communicating with the pressure relief air inlet end (11) and the pressure relief air outlet end (12); A burn-resistant structure, arranged at the pressure relief and exhaust end (12), the burn-resistant structure comprising a plurality of burn-resistant layers (2) sequentially spaced apart along the axial direction of the pressure relief and exhaust end (12); and A flow guide structure is arranged in the shell (1), along the flow direction of the pressure relief airflow in the shell (1), the flow guide structure is located upstream of the burn-resistant structure, and is used to divide the pressure relief airflow in the shell (1) into multiple regional airflows flowing toward different regions of the burn-resistant structure.

2. The fire-blocking structure according to claim 1, characterized in that: The flow guiding structure comprises: A cavity guide structure is arranged in the cavity (13) and is used to divide the pressure relief airflow flowing into the cavity (13) into an outer area airflow (G11) and an inner area airflow (G12) flowing in the outer area and the inner area of ​​the cavity (13) respectively, and to make the flow velocity of the outer area airflow (G11) greater than the flow velocity of the inner area airflow (G12), and / or to make the flow rate of the outer area airflow (G11) greater than the flow rate of the inner area airflow (G12).

3. The fire-blocking structure according to claim 1, characterized in that: The flow guiding structure comprises: A cavity guide structure is arranged in the cavity (13) and is used to divide the pressure relief airflow flowing into the cavity (13) into an outer ring area airflow (G21), an inner ring area airflow (G22) and a middle area airflow (G23) which are distributed in sequence from the outside to the inside in the cavity (13), and to make the flow velocity of the outer ring area airflow (G21), the flow velocity of the middle area airflow (G23) and the flow velocity of the inner ring area airflow (G22) distributed from large to small, and / or make the flow rate of the outer ring area airflow (G21), the flow rate of the middle area airflow (G23) and the flow rate of the inner ring area airflow (G22) distributed from large to small.

4. The fire-blocking structure according to claim 1, characterized in that: The flow guiding structure comprises a cavity flow guiding structure arranged in the cavity (13), and the cavity flow guiding structure comprises: The middle guide member (4) is arranged in alignment with the pressure relief air inlet end (11), and is used to divide the pressure relief airflow flowing from the pressure relief air inlet end (11) into the cavity (13) into an outer area airflow (G11) and an inner area airflow (G12) flowing in the outer area and the inner area of ​​the cavity (13) respectively.

5. The fire-blocking structure according to claim 4, characterized in that: The middle flow guide (4) is provided with a flow structure (41) running through it, and the middle flow guide (4) is further configured to divide the pressure relief airflow into an outer ring area airflow (G21), an inner ring area airflow (G22) and a middle area airflow (G23) which are sequentially distributed from the outside to the inside in the cavity (13).

6. The fire-blocking structure according to claim 4, characterized in that: The middle flow guide (4) is a curved plate (42) and the curved convex surface faces the pressure relief air inlet end (11).

7. The fire-blocking structure according to claim 4, characterized in that: The middle flow guide member (4) is a pressure relief valve disc (43) used for switching the on / off state between the cavity (13) and the pressure relief air inlet end (11).

8. The fire-blocking structure according to claim 4, characterized in that: The cavity guide structure also includes: A first annular flow guide (5) is arranged on the downstream side of the middle flow guide (4), the outer circumferential wall of the first annular flow guide (5) being spaced apart from the inner circumferential wall of the cavity (13), and the first annular flow guide (5) is used to further divide the outer area airflow (G11) and the inner area airflow (G12) into an outer annular area airflow (G21), an inner annular area airflow (G22) and a middle area airflow (G23) which are sequentially distributed from the outside to the inside in the cavity (13).

9. The fire-blocking structure according to claim 8, characterized in that: The cavity guide structure also includes: The second annular flow guide member (6) is arranged on the downstream side of the first annular flow guide member (5), the outer circumferential wall of the second annular flow guide member (6) is spaced apart from the inner circumferential wall of the cavity (13), and the outer ring radius of the second annular flow guide member (6) is greater than the outer ring radius of the first annular flow guide member (5).

10. The fire barrier structure according to any one of claims 1 to 9, characterized in that: The flow guiding structure comprises: An air inlet end guide structure is arranged in the pressure relief air inlet end (11) and is used to divide the pressure relief airflow flowing into the pressure relief air inlet end (11) into an outer area airflow (G31) and an inner area airflow (G32) flowing in the outer area and the inner area of ​​the pressure relief air inlet end (11) respectively, and to make the flow rate of the outer area airflow (G31) greater than the flow rate of the inner area airflow (G32), and / or to make the flow rate of the outer area airflow (G31) greater than the flow rate of the inner area airflow (G32).

11. The fire barrier structure according to any one of claims 1 to 9, characterized in that: The flow guiding structure comprises: The air inlet end guide structure is arranged in the pressure relief air inlet end (11) and is used to divide the pressure relief airflow flowing into the pressure relief air inlet end (11) into an outer area airflow (G31), an inner area airflow (G321) and an intermediate area airflow (G322) flowing in the outer area, the inner area and the middle area of ​​the pressure relief air inlet end (11) respectively, and makes the flow rate of the outer area airflow (G31), the flow rate of the middle area airflow (G322) and the flow rate of the inner area airflow (G321) distributed from large to small, and / or makes the flow rate of the outer area airflow (G31), the flow rate of the middle area airflow (G322) and the flow rate of the inner area airflow (G321) distributed from large to small.

12. The fire barrier structure according to any one of claims 1 to 9, characterized in that: The flow guiding structure comprises an air intake end flow guiding structure arranged in the pressure relief air intake end (11), and the air intake end flow guiding structure comprises: a first annular baffle (7), wherein the outer peripheral wall of the first annular baffle (7) is spaced apart from the inner peripheral wall of the pressure relief air inlet end (11), and the first annular baffle (7) is used to divide the pressure relief airflow flowing into the pressure relief air inlet end (11) into an outer layer area airflow (G31) flowing between the inner peripheral wall of the pressure relief air inlet end (11) and the outer peripheral wall of the first annular baffle (7) and an outer layer area airflow (G31) flowing in the pressure relief air inlet end (11) The inner area airflow (G32) flows inside the first annular partition (7).

13. The fire-blocking structure according to claim 12, characterized in that: The air intake end guide structure also includes: The second annular partition (8) is arranged inside the first annular partition (7) and is spaced apart from the first annular partition (7) inside and outside. The second annular partition (8) is used to divide the internal area airflow (G32) into an inner area airflow (G321) flowing between the first annular partition (7) and the second annular partition (8) and an intermediate area airflow (G322) flowing inside the second annular partition (8).

14. The fire-blocking structure according to claim 13, characterized in that: The burn-resistant layer (2) comprises an outer circulation structure, an inner circulation structure, and an intermediate circulation structure for respectively circulating the outer region airflow (G31), the inner region airflow (G321), and the intermediate region airflow (G322); the porosity of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are σ1, σ2, and σ3, respectively; the circulation areas of the outer circulation structure, the inner circulation structure, and the intermediate circulation structure are S1, S2, and S3, respectively; The inlet split ratio of the annular area between the inner circumferential wall of the pressure relief inlet end (11) and the outer circumferential wall of the first annular partition (7), the inlet split ratio of the annular area between the first annular partition (7) and the second annular partition (8), and the inlet split ratio of the inner area of ​​the second annular partition (8) are a, b, and c respectively; The total flow area at the inlet end of the inlet end flow guide structure is S0; it satisfies: (S1*σ1) / (S0*a)≤2 / 3; (S2*σ2) / (S0*b)≥5; 1≤(S3*σ3) / (S0*c)≤3.

15. The fire barrier structure according to any one of claims 1 to 14, characterized in that: The burn-resistant layer (2) comprises a burn-resistant layer outer ring zone (22a) and a burn-resistant layer inner zone located inside the burn-resistant layer outer ring zone (22a), and the porosity of the burn-resistant layer outer ring zone (22a) is greater than the porosity of the burn-resistant layer inner zone.

16. The fire-blocking structure according to claim 15, characterized in that: The inner area of ​​the burn-resistant layer includes an inner ring area (22b) of the burn-resistant layer and a middle area (22c) of the burn-resistant layer. The outer ring area (22a) of the burn-resistant layer, the inner ring area (22b) of the burn-resistant layer and the middle area (22c) of the burn-resistant layer are arranged in sequence from the outside to the inside. The porosity of the outer ring area (22a) of the burn-resistant layer, the porosity of the middle area (22c) of the burn-resistant layer and the porosity of the inner ring area (22b) of the burn-resistant layer are arranged from large to small.

17. The fire barrier structure according to any one of claims 1 to 16, characterized in that: The fire-blocking structure also includes: The heat-insulating support structure (3) is arranged between two adjacent burn-resistant layers (2) and is in contact with the two adjacent burn-resistant layers (2).

18. The fire-blocking structure according to claim 17, characterized in that: The thermal insulation support structure (3) is a multi-layer thermal insulation support structure, which includes a plurality of thermal insulation support units (31) stacked in sequence along the axial direction; or, the multi-layer thermal insulation support structure includes a thermal insulation support body portion (32a) and a thermal insulation support protrusion portion (32b) protruding from the thermal insulation support body portion (32a) along the axial direction.

19. The fire barrier structure according to claim 17 or 18, characterized in that: The heat-insulating support structure (3) forms point contact, line contact or surface contact with the burn-resistant layer (2).

20. The fire barrier structure according to any one of claims 1 to 19, characterized in that: The burn-resistant layer (2) comprises a burn-resistant layer outer ring area (22a) and a burn-resistant layer inner area located inside the burn-resistant layer outer ring area (22a), wherein the burn-resistant layer outer ring area (22a) can allow pressure relief air to flow, and the burn-resistant layer inner area is a closed heat-insulating area.

21. The fire-blocking structure according to claim 20, characterized in that: The burn-resistant layer (2) comprises a first closed heat-insulating disk (23a) and a plurality of first fire-blocking disks (23b); the outer ring area (22a) of the burn-resistant layer and the inner area of ​​the burn-resistant layer are both arranged on the first closed heat-insulating disk (23a); the outer ring area (22a) of the burn-resistant layer of the first closed heat-insulating disk (23a) is provided with a plurality of first embedding openings which are formed in a circumferential direction and are spaced in sequence; the plurality of first fire-blocking disks (23b) are embedded in the plurality of first embedding openings in a one-to-one correspondence.

22. The fire barrier structure according to any one of claims 1 to 19, characterized in that: Each of the burn-resistant layers (2) comprises a burn-resistant layer outer ring zone (22a), a burn-resistant layer inner ring zone (22b) and a burn-resistant layer middle zone (22c) arranged in sequence from the outside to the inside; the burn-resistant layer outer ring zone (22a) and the burn-resistant layer middle zone (22c) are both capable of allowing pressure relief airflow to circulate; and the burn-resistant layer inner ring zone (22b) is a closed heat-insulating zone.

23. The fire-blocking structure according to claim 22, characterized in that: The burn-resistant layer (2) comprises a second closed heat-insulating disk (24a), a plurality of second fire-blocking disks (24b) and a single third fire-blocking disk (24c); the outer ring area (22a) of the burn-resistant layer, the inner ring area (22b) of the burn-resistant layer and the middle area (22c) of the burn-resistant layer are all arranged on the second closed heat-insulating disk (24a); a plurality of second embedding openings formed in a circumferential direction and spaced in sequence are arranged in the outer ring area (22a) of the burn-resistant layer of the second closed heat-insulating disk (24a); a plurality of second fire-blocking disks (24b) are embedded in the plurality of second embedding openings in a one-to-one correspondence; a third embedding opening is arranged in the middle area (22c) of the burn-resistant layer of the second closed heat-insulating disk (24a); the third fire-blocking disk (24c) is embedded in the third embedding opening.

24. The fire-blocking structure according to claim 22, characterized in that: The burn-resistant layer (2) comprises a fire-blocking ring (25a), a closed heat-insulating ring (25b) and a fourth fire-blocking disk (25c) which are nested in sequence from the outside to the inside; the outer ring area (22a) of the burn-resistant layer is arranged on the fire-blocking ring (25a); the inner ring area (22b) of the burn-resistant layer is arranged on the closed heat-insulating ring (25b); and the middle area (22c) of the burn-resistant layer is arranged on the fourth fire-blocking disk (25c).

25. The fire barrier structure according to any one of claims 1 to 24, characterized in that: The burn-resistant layer (2) comprises a stacked porous burn-resistant layer, the stacked porous burn-resistant layer comprises a first shell (26a) and a plurality of stacked particles (26b) stacked in the first shell (26a), the upstream side wall and the downstream side wall of the first shell (26a) are both provided with a plurality of first shell through holes, the diameter of the first shell through holes is smaller than the diameter of the stacked particles (26b).

26. The fire-blocking structure according to claim 25, characterized in that: The distance between the upstream inner wall and the downstream inner wall of the first shell (26a) is the same as the total stacking thickness of the plurality of stacked particles (26b) along the axial direction of the stacked porous burn-resistant layer.

27. The fire barrier structure according to any one of claims 1 to 26, characterized in that: The burn-resistant layer (2) comprises a stacked porous burn-resistant layer, which comprises a second shell and a plurality of lightweight spheres stacked in the second shell and capable of rotating under the drive of a pressure relief airflow, wherein the upstream side wall and the downstream side wall of the second shell are both provided with a plurality of second shell through holes, and the diameter of the second shell through holes is smaller than the diameter of the lightweight spheres.

28. The fire barrier structure according to any one of claims 1 to 27, characterized in that: Among the plurality of burn-resistant layers (2), the burn-resistant layer (2) located most downstream is formed as a combustion-side burn-resistant layer (21a), and the combustion-side burn-resistant layer (21a) includes a burn-resistant layer disc portion (27a) and a burn-resistant layer convex portion (27b) connected to the downstream side of the burn-resistant layer disc portion (27a), and the downstream side surface of the burn-resistant layer convex portion (27b) is a partial spherical surface convexly arranged toward the downstream.

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