Simulation experiment device for reducing fire accident of sealing ring and accident consequence analysis method

Abstract

The invention relates to the technical field of oil and gas safe storage, and provides a simulation experiment device for reducing sealing ring fire accidents and an accident consequence analysis method. According to the experimental device, a target tank body containing fuel is simulated through a test tank body containing the fuel through a barreled structure with an opening in the upper end, and a floating disc of the target tank body is simulated through a liftable floating disc located in the barreled structure in the test tank body; the lower bottom surface of the liftable floating disc is adsorbed on the surface of the fuel to simulate mutual contact between the floating disc in the target tank body and the fuel, and an annular gap between the liftable floating disc and the inner side wall of the barreled structure of the test tank body simulates a sealing ring gap in the target tank body; the relation between the positions of the floating discs with different heights and a fire accident is simulated by utilizing the height adjustment of the liftable floating disc in the vertical direction when a sealing ring fire disaster occurs in a target tank body, the flame merging situation and the fuel boiling time in different combustion periods are analyzed, and a technical support is provided for fire rescue and personnel evacuation.

Description

Technical Field

[0001] The present application relates to the technical field of safe storage of oil and gas, and in particular to a simulation experimental device for reducing sealing ring fire accidents and an accident consequence analysis method. Background Art

[0002] In oil companies, refineries, petrochemical plants and other places, a large amount of oil products are stored in floating roof tanks. Among the floating roof tank leakage accidents, the most common is the seal ring fire. In the seal ring fire, if the fire is not extinguished in time at the early stage of the fire, it is likely that a special flame phenomenon of the floating roof oil tank seal ring fire will occur - the flame merging phenomenon. This extreme fire phenomenon is very destructive, and the fire will spread rapidly, posing a huge threat to the safety of surrounding personnel and facilities, making it difficult to carry out firefighting and rescue work. Therefore, the analysis of the seal ring fire is very important.

[0003] Based on the view that the fire of the actual tank seal ring is mainly concentrated on the annular seal ring in the early stage of combustion, at present, the hollow annular device (annular oil pool with a hollow center, such as Figure 1 The sealing ring fire is simulated by using a hollow annular oil pool in the middle (as shown). The floating plate part of the real tank is not retained. The parameters measured by the simulated annular fire experiment are far from the real sealing ring fire.

[0004] Therefore, there is an urgent need to provide a technical solution to the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The purpose of the present application is to provide a simulation experimental device for reducing sealing ring fire accidents and an accident consequence analysis method, so as to solve or alleviate the problems existing in the above-mentioned prior art.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] The present application provides a simulation experimental device for reducing sealing ring fire accidents, which is used for simulating sealing ring fire on a target tank body containing fuel, comprising: a test tank body, which is a barrel-shaped structure with an upper end open, and the test tank body contains fuel; a liftable floating plate, which is located in the barrel-shaped structure of the test tank body, and has a lower bottom surface adsorbed on the surface of the fuel, and an annular gap is left between the float and the inner side wall of the barrel-shaped structure of the test tank body; wherein the height of the liftable floating plate can be adjusted in the vertical direction.

[0008] Preferably, the liftable floating plate comprises: a floating plate adsorption unit, whose lower bottom surface is adsorbed on the fuel surface; and a floating plate movable unit, whose lower end is slidably inserted into the floating plate adsorption unit and can move up and down in a vertical direction relative to the floating plate adsorption unit.

[0009] Preferably, the floating plate adsorption unit is a barrel-shaped structure with an opening at the upper end, and an inner annular ear plate extends radially inward from the upper end opening, a plurality of vertical slide grooves evenly distributed along the circumferential direction are arranged on the inner side wall, and a plurality of pressure balance holes are opened on the top surface; the floating plate movable unit is a barrel-shaped structure with an opening at the lower end, and an outer annular ear plate extends radially outward from the lower end opening, and a plurality of vertical sliding blocks evenly distributed along the circumferential direction are arranged on the outer side wall of the outer annular ear plate; wherein, a plurality of the vertical sliding blocks are correspondingly slidably inserted in a plurality of the vertical slide grooves, and the inner annular ear plate, the outer annular ear plate, the inner side wall of the floating plate adsorption unit and the outer side wall of the floating plate movable unit form an annular cavity; the pressure balance hole is connected to the annular cavity.

[0010] Preferably, it also includes: a guide sealing column and an adjusting push rod; the guide sealing column is a cylindrical structure with openings at both ends, the lower end of which is detachably penetrated through the bottom of the barrel structure connected to the test tank body, and the upper end of which penetrates through the bottom of the barrel structure of the floating plate adsorption unit and extends into the barrel structure of the floating plate adsorption unit; an adjusting push rod is slidably mounted in the cylindrical structure of the guide sealing column, the upper end of which is detachably connected to the bottom plate of the barrel structure of the floating plate movable unit, and the lower end of which is connected to a telescopic driving unit; and the adjusting push rod is also provided with an air flow channel, the upper end of which is connected to an air flow hole provided on the bottom plate of the barrel structure of the floating plate movable unit, and the lower end of which is located on the outside of the bottom plate of the barrel structure of the test tank body; wherein the telescopic driving unit is used to drive the adjusting push rod to move up and down in a vertical direction.

[0011] Preferably, a limiting groove is further provided on the side wall of the adjusting push rod, an elastic limiting member is installed in the limiting groove, and the limiting groove is located between the lower end of the air flow channel and the bottom plate of the barrel structure of the test tank body.

[0012] Preferably, the liftable floating plate is made of titanium alloy.

[0013] An embodiment of the present application also provides a consequence analysis method for reducing sealing ring fire accidents, using any of the above-mentioned simulation experimental devices for reducing sealing ring fire accidents to simulate the sealing ring fire of a target oil tank, the analysis method comprising: determining the flame merging probability of the target oil tank when a sealing ring fire occurs based on the mass change rate of the experimental device during the experiment and based on a constructed flame merging probability model; determining the dimensionless duration of the stable period when a sealing ring fire occurs in the target oil tank based on a pre-constructed duration model according to the height of the liftable floating plate of the experimental device during the experiment, the mass change rate of the experimental device during the experiment, and the flame temperature and fuel temperature when a sealing ring fire occurs in the target oil tank.

[0014] Preferably, the flame merging probability model of the target oil tank is:

[0015]

[0016] Where γ1 is a constant, η is the ratio of the inner diameter to the outer diameter of the target oil tank, and A f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature of the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant; λ is the combustion efficiency of the fuel in the target oil tank, ΔH c is the combustion calorific value of the fuel in the target oil tank, δ is the mass change rate when a sealing ring fire occurs in the target oil tank, and β is the air entrainment rate when a sealing ring fire occurs in the target oil tank.

[0017] Preferably, according to the formula:

[0018]

[0019] Determine the air entrainment rate β when a seal ring fire occurs in the target oil tank;

[0020] Where λ is the combustion efficiency of the fuel in the target oil tank, δ is the mass change rate when the seal ring of the target oil tank is on fire, and ΔH c is the combustion calorific value of the fuel in the target oil tank, A f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature of the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant, g=9.8;

[0021] z is the flame height when the sealing ring fire occurs in the target oil tank, T f It is the flame temperature when a sealing ring fire occurs in the target oil tank.

[0022] Preferably, according to the formula:

[0023]

[0024] Determine the dimensionless duration of the stable period when the seal ring fire occurs in the target oil tank

[0025] Where ε is the combustion efficiency factor of the fuel in the target oil tank, δ is the mass change rate when the seal ring fire occurs in the target oil tank, and ΔH c is the combustion calorific value of the fuel in the target oil tank, A is the air volume inside the liftable floating plate of the experimental device; f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank; λ is the combustion efficiency of the fuel in the target oil tank; T f , T l are respectively the flame temperature when a seal ring fire occurs in the target oil tank and the fuel temperature in the target oil tank; η is the ratio of the inner diameter to the outer diameter of the target oil tank;

[0026] d is the diameter of the liftable floating plate of the experimental device; α ′ is the ratio of the maximum height of the floating roof of the target oil tank to the maximum rising height of the liftable floating plate of the experimental device; α″ is the ratio of the diameter of the floating roof of the target oil tank to the diameter of the liftable floating plate of the experimental device; r r is the floating roof radius of the target oil tank;

[0027] ρ Ti is the material density of the experimental device; h f is the height of the floating plate of the experimental device that can be raised and lowered.

[0028] Beneficial effects:

[0029] In the simulation experimental device for reducing sealing ring fire accidents provided in the embodiment of the present application, a test tank body containing fuel through a barrel structure with an opening at the upper end is used to simulate a target tank body containing fuel, a liftable floating plate in the barrel structure inside the test tank body is used to simulate the floating plate of the target tank body, the lower bottom surface of the liftable floating plate is adsorbed on the fuel surface to simulate the mutual contact between the floating plate and the fuel in the target tank body, and the annular gap between the liftable floating plate and the inner wall of the barrel structure of the test tank body is used to simulate the sealing ring gap in the target tank body, so as to simulate the sealing ring fire of the target tank body containing fuel, and the height of the liftable floating plate is adjusted in the vertical direction to simulate the relationship between the position of the floating plate at different heights and the fire accident during fuel combustion when a sealing ring fire occurs in the target tank body, and then the flame merging situation and the fuel boiling time in different combustion periods are analyzed, so as to provide technical support for firefighting rescue and personnel evacuation, so as to ensure that complex fire situations are fully responded to and more sufficient rescue time is provided for trapped personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. Among them:

[0031] Figure 1 It is a structural schematic diagram of a hollow annular device for simulating a sealing ring fire in the prior art;

[0032] Figure 2 A schematic structural diagram of a simulation experimental device for reducing fire accidents of sealing rings provided according to some embodiments of the present application;

[0033] Figure 3 A schematic diagram of the structure of a liftable floating plate provided according to some embodiments of the present application;

[0034] Figure 4 for Figure 3 A cross-sectional view of the liftable floating plate shown;

[0035] Figure 5 for Figure 4 The structural schematic diagram of the floating plate adsorption unit in the liftable floating plate is shown;

[0036] Figure 6 for Figure 5 A schematic diagram of the structure of a floating plate movable unit in a liftable floating plate is shown;

[0037] Figure 7 A schematic diagram of the structure of a guide sealing column provided according to some embodiments of the present application;

[0038] Figure 8 A schematic diagram of the structure of an adjusting push rod provided according to some embodiments of the present application;

[0039] Fig. 9 for Figure 8 A cross-sectional view of the adjustment push rod shown;

[0040] Fig.10 A flowchart of an accident consequence analysis method for reducing sealing ring fire accidents is provided according to some embodiments of the present application;

[0041] Fig.11 A schematic diagram of a sealing ring fire simulation scenario is provided according to some embodiments of the present application;

[0042] Fig.12 for Fig.11 Schematic diagram of the results of the sealing ring fire simulation.

[0043] Description of reference numerals:

[0044] 1: Test tank; 2: Liftable floating plate; 3: Guide sealing column; 4: Adjustment push rod; 5: Lifting drive unit; 6: Elastic limiter;

[0045] 201: floating plate adsorption unit; 203: floating plate movable unit; 211: adsorption cylinder; 221: adsorption bottom cover; 231: vertical slide; 241: pressure balance hole; 251: installation through hole; 212: air vent; 222: air flow hole;

[0046] 401: air flow channel. DETAILED DESCRIPTION

[0047] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present application and does not limit the present application. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as a part of an embodiment may be used in another embodiment to produce yet another embodiment. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the embodiments of the present invention should belong to the scope of protection of the embodiments of the present invention.

[0048] When a seal ring fire occurs in a real storage tank, although the fuel under the floating plate is not burned, there is a complex heat transfer process with the burning liquid surface. In the prior art, the hollow annular device (a hollow annular oil pool in the middle, such as Figure 1 As shown in the figure, only a hollow stainless steel ring structure is used, and a real tank floating plate is lacking, which makes it difficult to truly and effectively simulate the actual situation when a sealing ring fire occurs.

[0049] Based on this, the embodiment of the present application proposes a simulation experimental device for reducing sealing ring fire accidents, which adopts a floating plate type annular oil pool fire that can be raised and lowered to simulate the sealing ring fire, and simulates the floating plate structure of the external floating roof tank (target tank body) through a hollow lifting floating plate, replacing the hollow annular device of the traditional simulation experiment, which is more in line with the actual state of sealing ring fire and annular fire, and is more conducive to the analysis of actual floating roof tank sealing ring fire.

[0050] like Figures 2 to 9As shown, the simulation experimental device for reducing the sealing ring fire accident for simulating the sealing ring fire of the target tank body containing fuel comprises: a test tank body 1 and a liftable floating plate 2, wherein the test tank body 1 is a barrel structure with an upper end opening, and the same fuel as that contained in the target tank body (external floating roof tank) is contained inside, and is used for simulating the external floating roof tank; the liftable floating plate 2 is located in the barrel structure of the test tank body 1, and is used for simulating the floating plate structure in the external floating roof tank; the lower bottom surface of the liftable floating plate 2 is adsorbed on the fuel surface to simulate the mutual contact between the floating plate structure of the external floating roof tank and the fuel; an annular gap is left between the liftable floating plate 2 and the inner side wall of the test tank body 1, and is used for simulating the sealing ring gap between the inner side wall of the external floating roof tank and the floating plate structure of the external floating roof tank, so as to simulate the sealing ring fire of the target tank body containing fuel.

[0051] At the same time, the liftable floating plate 2 can be extended and retracted in the vertical direction inside the test tank body 1 to adjust the height of the liftable floating plate 2, thereby simulating the relationship between the position of the floating plate at different heights and the fire accident during fuel combustion when a sealing ring occurs in the external floating roof tank, and then analyzing the flame merging situation and fuel boiling time in different combustion periods, providing technical support for fire rescue and personnel evacuation, ensuring adequate response to complex fire situations, and providing more sufficient rescue time for trapped personnel.

[0052] In the present application, the test tank body 1 is seated on the fireproof board through the lower bracket, that is, a bracket is provided on the bottom surface of the barrel structure of the test tank body 1 for supporting the test tank body 1; at the same time, the bracket is seated on the fireproof board, and a weighing sensor is provided on the fireproof board. The weighing sensor is used to monitor the mass change during the experiment in real time. Here, the fireproof board can be used to isolate the temperature during the experiment to protect the sensor or other equipment and improve the accuracy of data collection.

[0053] An image acquisition device (e.g., a camera) is arranged outside (on the side or on the top) of the test tank 1 to acquire images of characteristic changes (e.g., changes in the flame shape) during the experiment; a thermocouple tree is also arranged outside the test tank 1, and a plurality of thermocouples are arranged on the thermocouple tree along the axis of the test tank 1 to monitor the flame temperature during the experiment. In addition, the thermal radiation during the experiment can be monitored in real time by a radiation heat flux meter arranged on the side of the test tank. At the same time, the weighing sensor, the image acquisition device, the thermocouple tree, and the radiation heat flux meter are all connected to a data acquisition board, and the data acquisition board is connected to a data processing device.

[0054] In the present application, the liftable floating plate 2 is located in the barrel structure of the test tank body 1, and the lower bottom surface is connected to the top surface of the fuel contained in the test tank body 1; the liftable floating plate 2 is a hollow structure, which can float on the top surface of the fuel under the buoyancy of the fuel, and the lower bottom surface of the liftable floating plate 2 is simultaneously adsorbed by the surface of the fuel, and then when the top surface of the liftable floating plate 2 moves upward, the lower bottom surface of the liftable floating plate 2 can be adsorbed on the surface of the fuel to prevent the liftable floating plate 2 from being separated from the fuel. At the same time, the up and down movement of the top surface of the liftable floating plate 2 can effectively change the air volume in the hollow structure of the liftable floating plate 2, so that when the fuel is burned, the conductive heat feedback of the fuel covered by the lower bottom surface of the liftable floating plate 2 can be effectively slowed down.

[0055] In a specific example, the liftable floating plate 2 is a hollow structure, including: a floating plate adsorption unit 201 and a floating plate movable unit 202, the lower bottom surface of the floating plate adsorption unit 201 is adsorbed on the fuel surface, and the lower end of the floating plate movable unit 202 is slidably inserted into the floating plate adsorption unit 201 from the upper end of the floating plate adsorption unit 201, so that the floating plate movable unit 202 can move up and down relative to the floating plate adsorption unit 201 in the vertical direction. The lower bottom surface of the floating plate adsorption unit 201 is adsorbed by the fuel, so that the floating plate movable unit 202 can always maintain contact with the top surface of the fuel when moving upward; the up and down movement of the floating plate movable unit 202 relative to the floating plate adsorption unit 201 allows the relative height of the floating plate top surface relative to the fuel surface to be adjusted during the experiment, so as to simulate the relationship between the floating plate structure at different heights in the external floating roof tank and the flame merging and fuel boiling time when a sealing ring fire occurs.

[0056] Specifically, the floating plate adsorption unit 201 is a barrel structure with an opening at the upper end, and an inner annular ear plate extends radially inward from the upper end opening, and a plurality of vertical slide grooves 231 evenly distributed along the circumferential direction are arranged on the inner side wall of the barrel structure; the floating plate activity unit 202 is a barrel structure with an opening at the lower end, and an outer annular ear plate extends radially outward from the lower end opening, and a plurality of vertical sliders evenly distributed along the circumferential direction are arranged on the outer side wall of the outer annular ear plate. The plurality of vertical sliders are correspondingly inserted and slidably inserted into the plurality of vertical slide grooves 231, and the vertical sliders slide in the vertical slide grooves 231 in the vertical direction, thereby changing the relative height between the top surface of the floating plate activity unit 202 and the top surface of the fuel.

[0057] Here, the inner wall of the inner annular ear plate is matched with the outer wall of the floating plate activity unit 202, and the outer wall of the outer annular ear plate is matched with the inner wall of the floating plate adsorption unit 201, so that the inner annular ear plate, the outer annular ear plate, the inner wall of the floating plate adsorption unit 201, and the outer wall of the floating plate activity unit 202 form an annular cavity; a plurality of pressure balance holes 241 are opened on the inner annular ear plate starting from its top surface in the vertical direction, and the plurality of pressure balance holes 241 are connected to the annular cavity, so that when the floating plate activity unit 202 moves up and down relative to the floating plate adsorption unit 201, the air pressure in the annular cavity remains balanced with the external air pressure. Furthermore, the pressure balance hole 241 is opened opposite to the vertical slide groove 231, which, on the one hand, facilitates the flow of gas inside and outside the annular cavity. At the same time, grease can be injected into the annular slide groove through the pressure balance hole 241 to lubricate the relative sliding between the vertical slider and the vertical slide groove 231, thereby reducing the sliding friction between the floating plate movable unit 202 and the floating plate fixed unit during relative movement.

[0058] In this embodiment, the floating plate adsorption unit 201 includes: an adsorption bottom cover 221 and an adsorption cylinder 211; wherein, the adsorption cylinder 211 is a cylindrical structure with openings at both ends, the upper end opening of the adsorption cylinder 211 has an inner annular ear plate extending radially inward, a plurality of vertical slide grooves 231 are provided on the inner side wall of the adsorption cylinder 211, and the lower end opening of the adsorption cylinder 211 is tightly matched with the adsorption bottom cover 221. Specifically, the lower end of the adsorption cylinder 211 is threadedly connected to the adsorption bottom cover 221. During the installation process, the adsorption active unit is inserted into the lower end opening of the adsorption cylinder 211 and extends out from the upper end opening of the adsorption cylinder 211; then, the adsorption bottom cover 221 and the lower end thread of the adsorption cylinder 211 are tightened.

[0059] In this embodiment, the up-and-down movement of the floating plate movable unit 202 relative to the floating plate fixed unit is driven by the lifting drive unit 5 (such as an air pump or an electric push rod, etc.). Specifically, a mounting through hole 251 is opened in the middle of the bottom plate of the barrel structure of the test tank body 1; the lifting drive unit 5 is located at the lower part of the test tank body 1, and the telescopic part of the lifting drive unit 5 can move up and down along the axis of the mounting through hole 251, and then, the up-and-down movement of the telescopic part drives the floating plate movable unit 202 to adjust its height relative to the floating plate fixed unit.

[0060] In a specific example, a guide sealing column 3 coaxial with the installation through hole 251 is arranged in the test tank body 1; wherein the guide sealing column is a cylindrical structure with two ends open, the lower end of the guide sealing column 3 can be detachably penetrated through the bottom of the barrel structure connected to the test tank body 1, and the upper end penetrates the bottom of the barrel structure of the floating plate adsorption unit 201 and extends into the barrel structure of the floating plate adsorption unit 201. Specifically, the lower end of the guide sealing column 3 is tightly matched with the installation through hole 251, and the upper end of the guide sealing column 3 passes through the surface of the liftable floating plate 2 in contact with the fuel and then extends into the hollow structure of the liftable floating plate 2; the telescopic part of the lifting drive unit 5 extends from the lower end of the guide sealing column 3, extends from the upper end of the cylindrical structure of the guide sealing column 3, and is connected to the floating plate movable unit 202 of the liftable floating plate 2, and then the telescopic part of the lifting drive unit 5 moves in the guide sealing column 3 along the circumferential direction, driving the floating plate movable unit 202 to move up and down relative to the floating plate adsorption unit 201.

[0061] In this embodiment, a mounting countersunk hole coaxial with the mounting through hole 251 is provided on the bottom plate of the test tank body 1, and correspondingly, a mounting boss is provided on the outer wall of the guide sealing column 3 near the lower end, and the mounting boss is tightly fitted with the mounting countersunk hole (for example, threaded connection, etc.); a section of the guide sealing column 3 that matches the mounting through hole 251 can be a tight fit or a clearance fit.

[0062] In another specific example, the coaxial sliding sleeve in the cylindrical structure of the guide sealing column 3 also has an adjusting push rod 4, and the upper end of the adjusting push rod 4 passes through the upper end of the guide sealing column 3 and is detachably connected to the bottom plate of the barrel structure of the floating plate movable unit 202, that is, after the upper end of the adjusting push rod 4 passes through the upper end of the cylindrical structure of the guide sealing column 3, it is detachably connected (for example, threaded connection) to the bottom plate of the floating plate movable unit 202. The lower end of the adjusting push rod 4 is connected to the telescopic part of the telescopic driving unit, so that, under the drive of the telescopic driving unit, the adjusting push rod 4 is driven to telescopically move in the guide sealing column 3, and the height of the top surface of the floating plate movable unit 202 relative to the top surface of the fuel is adjusted in real time and automatically.

[0063] During the installation process, firstly, the guide sealing column 3 is threadedly connected to the installation countersunk hole, or the guide sealing column 3 is tightly matched with the installation through hole 251, so that the guide sealing column 3 is firmly connected to the test tank body 1; at the same time, after the upper end of the adjusting push rod 4 is connected to the floating plate movable unit 202, the whole is loaded from the lower end of the adsorption cylinder 211, so that the vertical slide rail is adapted to the vertical slide groove 231, and finally, the adsorption bottom cover 221 is connected to the adsorption cylinder 211; after completing the connection between the liftable floating plate 2 and the adjusting push rod 4, the assembly of the liftable floating plate 2 and the adjusting push rod 4 is inserted downward from the upper end of the guide sealing column 3, and after passing through the lower end opening of the guide sealing column 3, it is connected to the telescopic part of the telescopic drive unit.

[0064] Here, it should be noted that a gap can be left between the guide sealing column 3 and the adjusting push rod 4, that is, the inner diameter of the cylindrical structure of the guide sealing column 3 is larger than the outer diameter of the adjusting push rod 4, and then the hollow structure of the lifting float 2 is connected to the outside of the test tank body 1, so that the air pressure in the hollow structure of the lifting float 2 is balanced with the external air pressure of the test tank body 1, so as to facilitate the up and down movement of the floating plate movable unit 202. In addition, a plurality of air holes 212 connected to the hollow structure can be opened on the top plate of the floating plate movable unit 202, so that the air flow inside the hollow structure can circulate with the air flow above the floating plate movable unit 202, and then, through the gap between the guide sealing column 3 and the adjusting push rod 4, the air flow above the floating plate movable unit 202 can circulate with the air flow below the test tank body 1, thereby increasing the air entrainment of the upper part of the floating plate movable unit 202 when the fuel is burning, and delaying the occurrence of flame merging in the early stage of combustion.

[0065] In another specific example, an air flow hole 222 is provided on the bottom plate of the barrel structure of the floating plate movable unit 202, and an air flow channel 401 is provided on the adjusting push rod 4. The upper end of the air flow channel 401 is connected to the air flow hole 222, and the lower end of the air flow channel 401 is located on the outside of the bottom plate of the barrel structure of the test tank body 1. Specifically, the air flow hole 222 is opened on the bottom plate of the floating plate movable unit 202 along the axial direction; an axial channel (not penetrating the bottom surface of the adjusting push rod 4) is opened on the adjusting push rod 4 starting from the top surface and downward along the axis, and a radial channel is opened on the upper edge of the outer wall of the adjusting push rod 4 extending out of the bottom surface of the test tank body 1, and the radial channel is connected with the axial channel to form the air flow channel 401. In addition, a plurality of threaded blind holes are provided on the lower end surface of the adjusting push rod 4 in the vertical direction, and the adjusting push rod 4 is connected to the telescopic part of the telescopic drive unit by screws.

[0066] After the adjustment push rod 4 is connected to the floating plate movable unit 202, the airflow channel 401 on the adjustment push rod 4 is connected to the airflow hole 222 on the floating plate movable unit 202, so that the upper airflow of the floating plate movable unit 202 and the lower airflow of the test tank body 1 can circulate, further enhancing the air suction of the upper part of the floating plate movable unit 202 during fuel combustion, and delaying the occurrence of flame merging in the early stage of combustion.

[0067] At the same time, a gas valve can also be set at the outlet of the radial channel of the adjusting push rod 4, and the opening and closing of the gas valve can control the disconnection of the upper airflow of the floating plate activity unit 202 and the lower airflow of the test tank body 1. When the fuel is burning, if the flame converges to the center (i.e., the flame merges), the gas valve can be opened to allow the upper airflow of the floating plate activity unit 202 to circulate with the lower airflow of the test tank body 1, thereby enhancing the air entrainment of the upper part of the floating plate activity unit 202 during fuel combustion, and delaying the occurrence of flame merging in the early stage of combustion, so as to facilitate the analysis of fire laws such as air entrainment rate, fuel mass change rate, and flame merging probability during the combustion process. In addition, the gas valve can also be closed to block the upper airflow of the floating plate activity unit 202 and the lower airflow of the test tank body 1, so as to push the floating plate activity unit 202 to rise, and further realize the law of the stable period of fuel combustion at different floating plate heights.

[0068] In another specific example, a limiting groove is further provided on the side wall of the adjusting push rod 4, and an elastic limiting member 6 is installed in the limiting groove, and the elastic limiting member 6 is located between the lower end of the airflow channel 401 and the bottom plate of the barrel structure of the test tank body 1. The radial dimension of the elastic limiting member 6 is larger than the radial dimension of the mounting through hole 251, and the rising stroke of the adjusting push rod 4 is less than or equal to the relative movement stroke between the floating plate movable unit 202 and the floating plate adsorption unit 201. Furthermore, the rising stroke of the adjusting push rod 4 is limited by the elastic limiting member 6, which effectively avoids the collision of the floating plate movable unit 202 with the floating plate adsorption unit 201 during the upward movement, and at the same time, it can effectively avoid driving the floating plate adsorption unit 201 away from the fuel liquid surface, further ensuring the accuracy of the experiment.

[0069] During the experiment, when the flames of the fuel combustion merge, there will be a period of stable combustion, that is, the stable period, and then the combustion rate will increase sharply, and the combustion will reach the overall boiling stage. By opening and closing the gas valve and adjusting the height of the elevating floating plate 2, the combustion laws of different floating plate heights, air entrainment rate, fuel mass change rate, flame merging probability, and combustion stable period during the fuel combustion process can be analyzed.

[0070] In a specific application scenario, different fuels are used to conduct experiments to obtain fire information and determine whether flame merging occurs in the early stage of combustion; if so, the gas valve is opened; if flame merging does not occur, the relationship between air entrainment rate, different combustion heat release rates, flame merging probability, etc. is established based on the fire data; after opening the gas valve, it is determined whether flame merging will occur at the same time. If so, the gas valve is closed to drive the floating plate activity unit to move, and the duration of the stable period of combustion at different floating plate heights is compared, and the relationship between the air volume in the hollow structure of the lifting floating plate, the floating plate heat conduction, the duration of the stable period, etc. is analyzed. In addition, the air entrainment rate, the mass change rate of the fuel, the flame merging, the duration of the stable period, etc. at different floating plate heights can also be analyzed.

[0071] In this scenario, in the early stage of the experiment, two different fuels, n-heptane and anhydrous ethanol, were used, and the combustion area was A. f =0.0325m 2 , the ratio of inner diameter to outer diameter η is 0.609, 0.732, 0.787, 0.830, 0.877, and five floating disk annular oil tanks (target oil tanks) TrayA, TrayB, TrayC, TrayD, and TrayE. In the simulation experimental device, the lifting float is made of titanium alloy with an adjustment stroke of 50mm; the experimental tank body is made of stainless steel with a height of 100mm; the fireproof board is 10mm thick; the thermocouple is a K-type armored thermocouple with a diameter of 1mm; four weighing sensors are arranged on the fireproof board, one image acquisition device is located at the edge of the test oil tank of the simulation experimental device, and the other image acquisition device is at a 45-degree angle to the ground to shoot down to record the flame fireworks process during the experiment. At the same time, according to the public experiment, the sealing ring fire simulation was carried out on 5 floating disk annular oil tanks with different inner and outer diameter ratios using two different fuels, n-heptane and anhydrous ethanol, and the initial thick layer thickness of the fuel was 30mm.

[0072] Specifically, Figures 10 to 12 As shown, the consequence analysis method for reducing the sealing ring fire accident provided in the embodiment of the present application uses the simulation experimental device for reducing the sealing ring fire accident of any of the above embodiments to simulate the sealing ring fire of the target oil tank, and the method includes:

[0073] Step S101: determining the flame merging probability of a target oil tank when a sealing ring fire occurs based on the mass change rate of the experimental device during the experiment and the constructed flame merging probability model.

[0074] During the experiment, anhydrous ethanol was used to conduct a floating plate oil pool fire experiment. Among the five floating plate annular oil tanks (target oil tanks) TrayA, TrayB, TrayC, TrayD, and TrayE, flames converged toward the center in TrayA, TrayB, and TrayC, and the gas valves of the corresponding target oil tanks were opened; subsequently, flame merging occurred in TrayA, while flame merging did not occur in oil tanks TrayB, TrayC, TrayD, and TrayE. For oil tanks TrayB, TrayC, TrayD, and TrayE, the regular relationship between air entrainment rate, fuel mass change rate, and flame merging was analyzed; after flame merging occurred in oil tank TrayA, the gas valve was closed, and the liftable floating plate was controlled to adjust the height, and the flame merging disappeared in oil tank TrayA, that is, there will be no stable period in the transition stage of oil tank TrayA. Therefore, there will be no sudden increase in flame height when oil tank TrayA reaches the overall boiling stage.

[0075] The flame merging probability model of the target oil tank is established as shown in the following formula:

[0076]

[0077]

[0078] Where γ1 is a constant, γ1 = 0.019, η is the ratio of the inner diameter to the outer diameter of the target oil tank, A f is the annular area between the inner wall of the target tank and the outer wall of the floating roof in the target tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature at the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant, g = 9.8; λ is the combustion efficiency of the fuel in the target oil tank, ΔH c is the combustion calorific value of the fuel in the target tank.

[0079] δ is the mass change rate when a seal ring fire occurs in the target oil tank, δ = Δm / Δt; where Δm is the mass change of the fuel in the test tank within the time interval Δt when the fuel is burning; β is the air entrainment rate when a seal ring fire occurs in the target oil tank.

[0080] At the same time, according to the formula:

[0081]

[0082] Determine the air entrainment rate β when the seal ring fire occurs in the target oil tank. In the formula, λ is the combustion efficiency of the fuel in the target oil tank, δ is the mass change rate when the seal ring fire occurs in the target oil tank, ΔH c is the combustion calorific value of the fuel in the target oil tank, A f is the annular area between the inner wall of the target tank and the outer wall of the floating roof in the target tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature of the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant, g = 9.8. z is the flame height when the seal ring of the target oil tank is on fire, T f It is the flame temperature when a sealing ring fire occurs in the target oil tank.

[0083] Step S102: According to the height of the liftable floating plate of the experimental device during the experiment, the mass change rate of the experimental device during the experiment, and the flame temperature and fuel temperature when the sealing ring fire occurs in the target oil tank, the dimensionless duration of the stable period when the sealing ring fire occurs in the target oil tank is determined based on a pre-constructed duration model.

[0084] The floating plate oil pool fire experiment was conducted using n-heptane. Among the five floating plate annular oil tanks (target oil tanks) TrayA, TrayB, TrayC, TrayD, and TrayE, the flames of the five oil tanks converged toward the center. After the gas valve of the target oil tank was opened, the flames of the five oil tanks merged. After the gas valve was closed and the height of the elevating floating plate was controlled to adjust, the flame merging phenomenon of the oil tanks TrayA and TrayB disappeared, while the flames of the oil tanks TrayC, TrayD, and TrayE remained merged. Therefore, for the oil tanks TrayC, TrayD, and TrayE, the duration of the stable period under different floating plate heights was compared, and the relationship between the air volume inside the hollow structure of the elevating floating plate, the floating plate heat conductivity, and the ratio of the different inner diameter to the outer diameter of the target oil tank η and the duration of the stable period under different floating plate heights was analyzed.

[0085] Specifically, according to the formula:

[0086]

[0087] Determine the dimensionless duration of the plateau period when a seal fire occurs in the target oil tank Where ε is the combustion efficiency factor of the fuel in the target oil tank, δ is the mass change rate when the seal ring fire occurs in the target oil tank, and ΔH c is the combustion calorific value of the fuel in the target tank, is the air volume inside the liftable floating disk of the experimental device; A f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank; λ is the combustion efficiency of the fuel in the target oil tank; T f , T l are the flame temperature when the seal ring fire occurs in the target oil tank and the fuel temperature in the target oil tank respectively; η is the ratio of the inner diameter to the outer diameter of the target oil tank;

[0088] d is the diameter of the liftable floating plate of the experimental device; α ′ is the ratio of the maximum height of the floating roof of the target oil tank to the maximum height of the liftable floating plate of the experimental device; α″ is the ratio of the diameter of the floating roof of the target oil tank to the diameter of the liftable floating plate of the experimental device; r r is the floating roof radius of the target oil tank; ρ Ti is the material density of the experimental device; h fis the height of the floating plate of the experimental device.

[0089] From the model of the dimensionless duration of the stable period when the seal ring fire occurs in the target oil tank, it can be seen that when the ratio of the inner diameter to the outer diameter of the target oil tank is the same, η, the height of the liftable floating plate is not adjusted, the air volume in the hollow structure of the liftable floating plate is small, and the overall heat conduction of the liftable floating plate is large, resulting in a shorter duration of the stable period. Therefore, the height of the liftable floating plate is controlled and adjusted to increase the air volume of the hollow structure in the liftable floating plate, slow down the overall conduction heat feedback of the liftable floating plate, effectively prolong the duration of the stable period in the combustion transition stage, and delay the time for the combustion to reach overall boiling, even if the time for the fire to increase is delayed. Furthermore, by correspondingly raising the height of the floating plate structure of the target oil tank, more time can be gained for fire rescue and personnel evacuation.

[0090] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0091] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0092] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0093] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", 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 may be combined in any one or more embodiments or examples in a suitable manner.

[0094] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A simulation experimental device for reducing fire accidents of sealing rings, characterized in that: Used to simulate the seal fire of the target tank containing fuel, including: The test tank body is a barrel structure with an upper opening, and the test tank body contains fuel; The liftable floating plate is located in the barrel structure of the test tank body, with its lower bottom surface adsorbed on the fuel surface and an annular gap between the floating plate and the inner wall of the barrel structure of the test tank body; wherein the height of the liftable floating plate can be adjusted in the vertical direction.

2. The simulation experimental device for reducing seal ring fire accidents according to claim 1 is characterized in that: The liftable floating plate comprises: A floating plate adsorption unit, the bottom surface of which is adsorbed on the fuel surface; The floating plate movable unit has its lower end slidably inserted into the floating plate adsorption unit and can move up and down relative to the floating plate adsorption unit in a vertical direction.

3. The simulation experimental device for reducing seal ring fire accidents according to claim 2 is characterized in that: The floating plate adsorption unit is a barrel structure with an opening at the upper end, and an inner annular ear plate extends radially inward from the upper end opening, a plurality of vertical slide grooves evenly distributed along the circumferential direction are arranged on the inner side wall, and a plurality of pressure balance holes are opened on the top surface; The floating plate movable unit is a barrel-shaped structure with an opening at the lower end, and an outer annular ear plate is radially extended outward from the lower end opening, and a plurality of vertical sliding blocks evenly distributed along the circumferential direction are arranged on the outer side wall of the outer annular ear plate; Among them, the multiple vertical sliding blocks are correspondingly slidably inserted in the multiple vertical sliding grooves, the inner annular ear plate, the outer annular ear plate, the inner wall of the floating plate adsorption unit, and the outer wall of the floating plate movable unit form an annular cavity; the pressure balance hole is connected to the annular cavity.

4. The simulation experimental device for reducing seal ring fire accidents according to claim 3 is characterized in that: Also includes: Guide sealing column and adjustment push rod; The guide sealing column is a cylindrical structure with two ends opened, the lower end of which is detachably penetrated through the bottom of the barrel structure connected to the test tank body, and the upper end of which penetrates through the bottom of the barrel structure of the floating plate adsorption unit and extends into the barrel structure of the floating plate adsorption unit; An adjusting push rod is slidably sleeved in the cylindrical structure of the guide sealing column, the upper end of which is detachably connected to the bottom plate of the barrel structure of the floating plate movable unit, and the lower end of which is connected to a telescopic driving unit; and the adjusting push rod is also provided with an air flow channel, the upper end of which is communicated with an air flow hole provided on the bottom plate of the barrel structure of the floating plate movable unit, and the lower end of which is located on the outer side of the bottom plate of the barrel structure of the test tank body; Wherein, the telescopic driving unit is used to drive the adjusting push rod to move up and down in the vertical direction.

5. The simulation experimental device for reducing seal ring fire accidents according to claim 4 is characterized in that: A limiting groove is also provided on the side wall of the adjusting push rod, an elastic limiting member is installed in the limiting groove, and the limiting groove is located between the lower end of the air flow channel and the bottom plate of the barrel structure of the test tank body.

6. The simulation experimental device for reducing seal ring fire accidents according to claim 1 is characterized in that: The liftable floating plate is made of titanium alloy.

7. A consequence analysis method for reducing sealing ring fire accidents, characterized in that: The sealing ring fire simulation is performed on a target oil tank using the simulation experimental device for reducing sealing ring fire accidents as described in any one of claims 1 to 6, and the analysis method includes: Determining the flame merging probability of the target oil tank when a sealing ring fire occurs according to the mass change rate of the experimental device during the experiment and based on the constructed flame merging probability model; According to the height of the liftable floating plate of the experimental device during the experiment, the mass change rate of the experimental device during the experiment, and the flame temperature and fuel temperature when the sealing ring fire occurs in the target oil tank, based on a pre-constructed duration model, the dimensionless duration of the stable period when the sealing ring fire occurs in the target oil tank is determined.

8. The method for analyzing the consequences of reducing seal ring fire accidents according to claim 7, characterized in that: The flame merging probability model of the target oil tank is: Where γ1 is a constant, η is the ratio of the inner diameter to the outer diameter of the target oil tank, and A f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature of the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant; λ is the combustion efficiency of the fuel in the target oil tank, ΔH c is the combustion calorific value of the fuel in the target oil tank; δ is the mass change rate when a seal ring fire occurs in the target oil tank, and β is the air entrainment rate when a seal ring fire occurs in the target oil tank.

9. The consequence analysis method for reducing seal ring fire accidents according to claim 8 is characterized in that: According to the formula: Determine the air entrainment rate β when a seal ring fire occurs in the target oil tank; Where λ is the combustion efficiency of the fuel in the target oil tank, δ is the mass change rate when the seal ring of the target oil tank is on fire, and ΔH c is the combustion calorific value of the fuel in the target oil tank, A f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank, ρ ∞ is the ambient air density under standard atmospheric pressure, C P is the specific heat capacity at constant pressure, T ∞ is the ambient temperature of the target oil tank; D is the characteristic diameter, which is the equivalent diameter of a circle with the same area as the annular gap between the liftable floating plate of the experimental device and the test tank of the experimental device; g is a constant; z is the flame height when the seal ring fire occurs in the target oil tank, T f It is the flame temperature when a sealing ring fire occurs in the target oil tank.

10. The consequence analysis method for reducing seal ring fire accidents according to claim 7, characterized in that: According to the formula: Determine the dimensionless duration of the stable period when the seal ring fire occurs in the target oil tank Where ε is the combustion efficiency factor of the fuel in the target oil tank, δ is the mass change rate when the seal ring fire occurs in the target oil tank, and ΔH c is the combustion calorific value of the fuel in the target oil tank, V O2 A is the air volume inside the liftable floating plate of the experimental device; f is the annular area between the inner wall of the target oil tank and the outer wall between the floating roof in the target oil tank; λ is the combustion efficiency of the fuel in the target oil tank; T f , T l are respectively the flame temperature when a seal ring fire occurs in the target oil tank and the fuel temperature in the target oil tank; η is the ratio of the inner diameter to the outer diameter of the target oil tank; d is the diameter of the liftable floating plate of the experimental device; α ′ is the ratio of the maximum height of the floating roof of the target oil tank to the maximum rising height of the liftable floating plate of the experimental device; α ″ is the ratio of the floating roof diameter of the target oil tank to the diameter of the liftable floating plate of the experimental device; r r is the floating roof radius of the target oil tank; ρ Ti is the material density of the experimental device; h f is the height of the floating plate of the liftable floating plate of the experimental device.

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