Analytical method, device and system for fire spread mechanism of molten dripping materials

Abstract

The present invention provides a method, device, and system for analyzing the fire spread mechanism of molten dripping materials. The method comprises: selecting a target analysis model in PFEM software and inputting solid-phase pyrolysis parameters and the viscosity coefficient required for particle motion into the target analysis model; setting initial conditions for the target analysis model during the fire spread process of the molten dripping material; setting boundary conditions for the target analysis model during the fire spread process of the molten dripping material; and numerically simulating the fire spread process of the molten dripping material using the target analysis model to obtain numerical simulation results of the fire spread of the molten dripping material, thereby analyzing the fire spread mechanism of the molten dripping material. The solution of the present invention can effectively analyze the fire spread mechanism of molten dripping materials.

Description

Technical Field

[0001] The present invention relates to the technical field of fire spread mechanism analysis, and in particular to an analysis method, device and system for the fire spread mechanism of molten dripping materials. Background Art

[0002] With the rapid development of my country's economy, molten dripping materials (such as thermoplastic polymer materials) have been widely used in various industries such as manufacturing, transportation, textiles, and construction due to their low cost and high ductility. This material will melt and become a fluid state when heated. When the gravity of the molten droplets overcomes the surface tension, dripping will occur. When such molten dripping materials (such as polyethylene, polyvinyl chloride, polypropylene and polystyrene, etc.) are used in the insulation layer of the exterior wall of a building, decorative materials and wire insulation layer, if a fire occurs, the molten dripping material burns to produce molten droplets. These high-temperature droplets usually carry flames and ignite other combustible materials during the dripping process to form a new fire source, further accelerating the spread and development of the fire. Therefore, it is necessary to analyze the fire spread mechanism of molten dripping materials in order to provide a scientific basis for scientifically controlling the molten dripping phenomenon in fires.

[0003] Prior art research on the fire spread mechanism of molten dripping materials has primarily focused on qualitative or semi-quantitative assessments of their dripping behavior, such as the UL-94 vertical burn test. However, these experimental results exhibit significant fluctuations, poor repeatability, and difficulty in quantitatively determining boundary conditions, making them incapable of providing effective data for numerical simulations. This has significantly hindered research on the fire spread mechanism of molten dripping materials.

[0004] Therefore, it is necessary to provide an analysis method, device and system for the fire spread mechanism of molten dripping materials to effectively analyze the fire spread mechanism of molten dripping materials. Summary of the Invention

[0005] The embodiments of the present invention provide a method, device, and system for analyzing the fire spread mechanism of molten dripping materials, which can effectively analyze the fire spread mechanism of molten dripping materials.

[0006] In a first aspect, an embodiment of the present invention provides a method for analyzing the fire spread mechanism of molten dripping materials, comprising:

[0007] Selecting a target analysis model in the PFEM software, and inputting solid phase pyrolysis parameters and a viscosity coefficient required for particle motion into the target analysis model;

[0008] Setting initial conditions for the target analysis model during the fire spread process of molten dripping material;

[0009] Setting boundary conditions for the target analysis model during the fire spread process of molten dripping material;

[0010] The target analysis model is used to perform numerical simulation on the fire spread process of the molten dripping material, and the numerical simulation results of the fire spread of the molten dripping material are obtained to analyze the fire spread mechanism of the molten dripping material.

[0011] In a second aspect, an embodiment of the present invention provides an analysis device for the fire spread mechanism of molten dripping materials, comprising:

[0012] An input module, used to select a target analysis model in the PFEM software and input solid phase pyrolysis parameters and a viscosity coefficient required for particle motion into the target analysis model;

[0013] A first setting module is used to set the initial conditions of the target analysis model in the molten dripping material fire spread process;

[0014] A second setting module is used to set the boundary conditions of the target analysis model during the fire spread process of the molten dripping material;

[0015] The numerical simulation module is used to perform numerical simulation on the fire spread process of the molten dripping material using the target analysis model, obtain the numerical simulation results of the fire spread of the molten dripping material, and analyze the fire spread mechanism of the molten dripping material.

[0016] In a third aspect, an embodiment of the present invention provides an electronic device, comprising: at least one memory and at least one processor;

[0017] The at least one memory is configured to store a machine-readable program;

[0018] The at least one processor is configured to call the machine-readable program to execute the method described above.

[0019] In a fourth aspect, an embodiment of the present invention provides an analysis system for the fire spread mechanism of molten dripping materials, comprising a molten dripping material fire spread parameter measuring device and an electronic device as described above, wherein the electronic device is used to compare the numerical simulation results with the actual results to verify the target analysis model.

[0020] It can be seen from the above scheme that the analysis method, device and system for the fire spread mechanism of molten dripping materials provided by the present invention can analyze the fluid-solid coupling problem with the help of PFEM software by inputting the solid-phase pyrolysis parameters and the viscosity coefficient required for particle movement into the target analysis model selected in the PFEM software, thereby better simulating the molten dripping of the molten dripping material. Then, the initial conditions and boundary conditions of the target analysis model in the fire spread process of the molten dripping material are set, so that the final numerical simulation results of the fire spread of the molten dripping material can be obtained, so as to effectively analyze the fire spread mechanism of the molten dripping material. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a flow chart of a method for analyzing the fire spread mechanism of molten dripping materials provided by one embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of an electronic device provided by one embodiment of the present invention;

[0024] Figure 3 Schematic diagram of an analysis device for the fire spread mechanism of molten dripping materials provided by one embodiment of the present invention;

[0025] Figure 4 is a structural diagram of a solid phase region and a gas phase region in a numerical simulation provided by one embodiment of the present invention;

[0026] Figure 5 It is a structural diagram of a measuring device provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] Figure 1 FIG. 1 is a flow chart of a method for analyzing the fire spread mechanism of molten dripping materials provided by one embodiment of the present invention. Figure 1As shown, the method may include the following steps:

[0029] Step 100: Select a target analysis model in the PFEM software, and input the solid phase pyrolysis parameters and the viscosity coefficient required for particle movement into the target analysis model;

[0030] Step 102: setting the initial conditions of the target analysis model in the fire spread process of the molten dripping material;

[0031] Step 104: setting boundary conditions for the target analysis model during the fire spread process of the molten dripping material;

[0032] Step 106 : numerically simulate the fire spread process of the molten dripping material using the target analysis model to obtain numerical simulation results of the fire spread of the molten dripping material, so as to analyze the fire spread mechanism of the molten dripping material.

[0033] In this embodiment, by inputting the solid-phase pyrolysis parameters and the viscosity coefficient required for particle movement into the target analysis model selected in the PFEM software, the fluid-solid coupling problem can be analyzed with the help of the PFEM software, so that the molten dripping of the molten dripping material can be better simulated. Then, the initial conditions and boundary conditions of the target analysis model in the fire spread process of the molten dripping material are set, so that the final numerical simulation results of the fire spread of the molten dripping material can be obtained, so as to effectively analyze the fire spread mechanism of the molten dripping material.

[0034] It should be noted that due to the heat-melting characteristics of molten dripping materials, the dripping of high-temperature molten droplets will ignite other flammable materials and increase the impact of fire. On the other hand, the molten droplets carry heat away from the material and will also affect the combustion of the material itself. In existing related studies, the impact of molten dripping behavior on fire spread is often ignored or simplified, so it is impossible to accurately predict the combustion and fire spread of molten dripping materials.

[0035] In addition, the current major fire numerical simulation software, such as FDS (Fire Dynamics Simulator), cannot quantitatively analyze molten flow dripping, and therefore cannot accurately simulate the fire spread engineering of molten dripping materials. FDS needs to be developed or other numerical simulation methods need to be used to make up for the current shortcomings. PFEM, also known as the particle finite element method, is a commonly used numerical simulation method for analyzing fluid-structure interaction problems. It was developed by the International Center for Numerical Methods in Engineering (CIMNE) in Spain. PFEM can analyze fluid-structure interaction problems, including large-scale continuous deformation, coupled thermal effects, droplet breakup and separation, and has been proven to be a powerful tool for modeling and analyzing complex multidisciplinary problems in fluid and solid mechanics. It can effectively simulate the molten dripping of molten dripping materials.

[0036] Each step is described in detail below.

[0037] For step 100:

[0038] In one embodiment of the present invention, the solid-phase pyrolysis parameters are obtained by a thermogravimetric analyzer, a differential scanning calorimeter, a micro-combustion calorimeter, and a controlled atmosphere pyrolyzer, and the viscosity coefficient required for particle movement is obtained by a rheometer.

[0039] In one embodiment of the present invention, the solid-phase pyrolysis parameters include the reaction kinetic parameters of the pyrolysis of the molten dripping material, the reaction thermodynamic parameters of the pyrolysis of the molten dripping material, the combustion heat of the combustible phase products generated by the molten dripping material during the pyrolysis reaction, and the component density and thermal conductivity of the molten dripping material during the pyrolysis reaction; wherein the reaction kinetic parameters include the Arrhenius pre-exponential factor, activation energy, stoichiometric coefficient and residual carbon yield, and the reaction thermodynamic parameters include specific heat capacity and the heat absorbed or released by the reaction.

[0040] In one embodiment of the present invention, a thermogravimetric analyzer is used to measure the mass loss data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction kinetic parameters;

[0041] Differential scanning calorimetry is used to measure the endothermic and exothermic data of molten dripping materials during the pyrolysis reaction to invert the reaction thermodynamic parameters;

[0042] The micro combustion calorimeter is used to measure the heat release data of the pyrolysis gas phase products of molten dripping materials when they are completely burned in excess oxygen, so as to invert the combustion heat of the combustible phase products.

[0043] The controlled atmosphere pyrolyzer is used to measure the back temperature, mass data and morphological data of molten dripping materials exposed to radiant heat, and to invert the component density and thermal conductivity by coupling the reaction kinetic parameters, reaction thermodynamic parameters and combustion heat of the combustible gas phase products obtained by inversion.

[0044] Thermogravimetric Analysis (TGA) can measure the mass loss of molten dripping materials during the pyrolysis reaction, and obtain the normalized mass loss (Normalized Mass) of the initial mass and the mass loss rate (Normalized Mass Loss Rate) curves as a function of time or temperature. Based on this, the reaction kinetic parameters of the pyrolysis of molten dripping materials can be inversely calculated, including the Arrhenius pre-exponential factor, activation energy, stoichiometric coefficient, and residual carbon yield.

[0045] Differential Scanning Calorimetry (DSC) can measure the endothermic and exothermic behavior of molten dripping materials during the pyrolysis reaction. The curves of the heat flow and the integral of the heat flow normalized by the initial mass versus time or temperature can be obtained. From these curves, the thermodynamic parameters of the pyrolysis of molten dripping materials, including specific heat capacity and the amount of heat absorbed or released by the reaction, can be inversely calculated.

[0046] The Microscale Combustion Calorimeter (MCC) can measure the heat release rate (Heat Release Rate) and total heat release (Total Heat Release) of the pyrolysis gas phase products of the molten dripping material when they are completely burned in excess oxygen. The curve of the change with time or temperature can be used to inversely calculate the heat of combustion (Heat of Combustion) of the combustible gas phase products generated during the pyrolysis reaction of the molten dripping material.

[0047] The Controlled Atmosphere Pyrolysis Apparatus (CAPA II) simultaneously measures the back-temperature, mass, and morphological changes of samples exposed to radiant heat. This data, combined with the aforementioned "TGA-DSC-MCC" multi-step milligram-scale thermal analysis and absorption coefficient measurements, allows the inversion of component densities and thermal conductivity during the sample's pyrolysis evolution, enabling the development of an accurate solid-phase pyrolysis model.

[0048] Compared with the method of using a single experiment such as cone calorimetry to invert all physical parameter data, this method of milligram scale experiment-gram scale experiment (TGA-DSC-MCC-CAPA) can more accurately obtain the physical properties of molten dripping materials by decoupling the chemical reaction and heat and mass transfer process of the material, thereby increasing the accuracy of the inversion results.

[0049] That is, in the related art, usually only a controlled atmosphere pyrolyzer is used to roughly obtain the above-mentioned solid-phase pyrolysis parameters. However, the embodiments of the present invention use "TGA-DSC-MCC" to decouple the solid-phase pyrolysis parameters except for the component density and thermal conductivity. That is, these parameters are first accurately calculated. In this way, the component density and thermal conductivity finally calculated by CAPA will be more accurate, thereby ensuring the accuracy of the target analysis model simulation.

[0050] Regarding steps 102 and 104:

[0051] See also Figure 4 , Figure 4 This is the structural diagram of the solid phase region and the gas phase region in the numerical simulation.

[0052] Solid phase: includes the viscosity coefficient (a function of temperature) required for solid phase pyrolysis (measured by the above device) and particle motion (caused by melt dripping), measured by a rheometer.

[0053] Gas phase: Solid pyrolysis products burn in the gas phase, and the conservation of mass, conservation of energy, and Navier-Stokes equations need to be solved.

[0054] The solid and gas phase calculations are interdependent, requiring the two computational modules to be coupled. Lagrangian finite element methods are used for solid phase simulations, while Euler descriptions are employed for the gas phase region. The Dirichlet-Neumann scheme is employed for the solid-gas interface.

[0055] In one embodiment of the present invention, step 102 may specifically include:

[0056] The solid phase temperature (e.g., room temperature), gas phase temperature (e.g., room temperature), oxygen (e.g., 21%), and mass fraction of pyrolysis products (e.g., 0) of the molten dripping material are set; wherein, when the temperature of the solid-gas interface reaches the preset ignition temperature, the mass fraction of oxygen is set to 0, and the mass fraction of pyrolysis products is set to 1.

[0057] In one embodiment of the present invention, step 104 may specifically include:

[0058] The gas velocity and temperature gradient of the middle symmetry plane of the molten droplet material along the vertical direction are both set to 0. The solid phase region and the gas phase region are both regarded as rectangular parallelepipeds (the sizes of the two rectangular parallelepipeds are set during the simulation). The solid phase region is the region of the molten droplet material, and the solid phase region is located in the gas phase region.

[0059] The simulation of the igniter (not shown in the figure) is simplified to add a fixed heat flux value to the surface of the molten dripping material;

[0060] A constant uniform velocity was set at the bottom inlet of the gas phase region;

[0061] The relative pressure at the top outlet of the gas phase region was set to 0.

[0062] In the above embodiment, accurate numerical simulation results can be obtained by reasonably setting the initial conditions and boundary conditions.

[0063] In order to better model the Figure 5The measuring device shown in the figure includes a molten dripping material 1 to be measured, a fixing frame 2 coated with the molten dripping material 1 to be measured, a thermocouple 3 for measuring the back temperature of the molten dripping material 1 to be measured, an angle adjuster 4 connected to the fixing frame 2, a first frame 5 connected to the angle adjuster 4, a first electronic balance 6 supporting the first frame 5, a fixing base 7 supporting the first electronic balance 6, a second frame 8 connected to the fixing base 7, and a second electronic balance 9 fixed to the second frame 8. The portion of the fixing frame 2 in contact with the molten dripping material 1 to be measured is made of a heat-insulating material. The molten dripping material 1 to be measured is a rectangular parallelepiped with its front end face in contact with the air. The angle adjuster 4 is used to adjust the angle of the fixing frame 2 relative to the horizontal plane. The first electronic balance 6 is used to measure the mass change rate of the molten dripping material 1 to be measured. The second electronic balance 9 is used to measure the mass change rate of the molten droplet of the molten dripping material 1 to be measured.

[0064] In one embodiment of the present invention, after step 106, the above method may further include:

[0065] Obtain the actual results measured by the constructed molten dripping material fire spread parameter measurement device; wherein both the numerical simulation results and the actual results include the spatiotemporal distribution of the back temperature of the molten dripping material, the mass change rate of the molten dripping material, and the mass change rate of the molten droplet;

[0066] Compare numerical simulation results with actual results;

[0067] If the error between the numerical simulation results and the actual results is lower than the preset error range, it means that the accuracy of the target analysis model meets expectations.

[0068] In this example, a measurement device was constructed and the actual results obtained were compared with the numerical simulation results to verify the accuracy of the target analysis model. This target analysis model can also be used to simulate other molten dripping materials, reducing the cost of setting up actual combustion experiments.

[0069] It should be noted that the embodiments of the present invention do not specifically limit the target analysis model, initial conditions, and boundary conditions.

[0070] like Figure 2 and Figure 3 As shown, the embodiment of the present invention provides an electronic device and an analysis device for the fire spread mechanism of molten dripping materials. The device embodiment can be implemented by software, hardware, or a combination of software and hardware. From the hardware level, such as Figure 2 As shown, it is a hardware structure diagram of an electronic device provided by an embodiment of the present invention, except Figure 2In addition to the processor, memory, network interface, and non-volatile memory shown, the device in the embodiment may also include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 3 As shown, as a device in a logical sense, the CPU of the device in which it is located reads the corresponding computer program instructions in the non-volatile memory into the internal memory and runs them.

[0071] like Figure 3 As shown, the analysis device for the fire spread mechanism of molten dripping materials provided in this embodiment includes:

[0072] An input module 300 is used to select a target analysis model in the PFEM software and input solid phase pyrolysis parameters and a viscosity coefficient required for particle motion into the target analysis model;

[0073] The first setting module 302 is used to set the initial conditions of the target analysis model in the molten dripping material fire spread process;

[0074] The second setting module 304 is used to set the boundary conditions of the target analysis model in the process of fire spread of molten dripping material;

[0075] The numerical simulation module 306 is used to perform numerical simulation on the fire spread process of the molten dripping material using the target analysis model to obtain numerical simulation results of the fire spread of the molten dripping material so as to analyze the fire spread mechanism of the molten dripping material.

[0076] In an embodiment of the present invention, the input module 300 can be used to execute step 100 in the above method embodiment, the first setting module 302 can be used to execute step 102 in the above method embodiment, the second setting module 304 can be used to execute step 104 in the above method embodiment, and the numerical simulation module 306 can be used to execute step 106 in the above method embodiment.

[0077] In one embodiment of the present invention, the solid-phase pyrolysis parameters are obtained by a thermogravimetric analyzer, a differential scanning calorimeter, a micro combustion calorimeter and a controlled atmosphere pyrolyzer, and the viscosity coefficient required for particle movement is obtained by a rheometer.

[0078] In one embodiment of the present invention, the solid-phase pyrolysis parameters include reaction kinetic parameters of the pyrolysis of molten dripping materials, reaction thermodynamic parameters of the pyrolysis of molten dripping materials, combustion heat of combustible gas phase products generated during the pyrolysis reaction of the molten dripping materials, and component density and thermal conductivity of the molten dripping materials during the pyrolysis reaction; wherein, the reaction kinetic parameters include Arrhenius pre-exponential factor, activation energy, stoichiometric coefficient and residual carbon yield, and the reaction thermodynamic parameters include specific heat capacity and heat absorbed or released by the reaction.

[0079] In one embodiment of the present invention, the thermogravimetric analyzer is used to measure the mass loss data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction kinetic parameters;

[0080] The differential scanning calorimeter is used to measure the endothermic and exothermic data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction thermodynamic parameters;

[0081] The micro combustion calorimeter is used to measure the heat release data of the pyrolysis gas phase products of the molten dripping material when they are completely burned in excess oxygen, so as to invert the combustion heat of the combustible phase products;

[0082] The controlled atmosphere pyrolyzer is used to measure the back temperature, mass data and morphological data of the molten dripping material exposed to radiant heat, and to invert the component density and the thermal conductivity by coupling the reaction kinetic parameters, the reaction thermodynamic parameters and the combustion heat of the combustible gas phase products obtained by inversion.

[0083] In one embodiment of the present invention, the first setting module is configured to perform the following operations:

[0084] The solid phase temperature, gas phase temperature, and mass fractions of oxygen and pyrolysis products of the molten dripping material are set; when the temperature of the solid-gas interface reaches the preset ignition temperature, the mass fraction of oxygen is set to 0, and the mass fraction of pyrolysis products is set to 1.

[0085] In one embodiment of the present invention, the second setting module is configured to perform the following operations:

[0086] The gas velocity and temperature gradient of the middle symmetry plane of the molten droplet material along the vertical direction are both set to 0; wherein the solid phase region and the gas phase region are both regarded as rectangular parallelepipeds, the solid phase region is the region of the molten droplet material, and the solid phase region is located in the gas phase region;

[0087] The simulation of the igniter is simplified to adding a fixed heat flux value to the surface of the molten dripping material;

[0088] Setting a constant uniform velocity at the bottom inlet of the gas phase region;

[0089] The relative pressure at the top outlet of the gas phase region was set to 0.

[0090] In one embodiment of the present invention, it further comprises:

[0091] An acquisition module is used to obtain the actual results measured by the constructed molten dripping material fire spread parameter measurement device; wherein, the measurement device includes a molten dripping material to be measured, a fixing frame coated on the molten dripping material to be measured, a thermocouple for measuring the back temperature of the molten dripping material to be measured, an angle adjuster connected to the fixing frame, a first frame connected to the angle adjuster, a first electronic balance supporting the first frame, a fixing seat supporting the first electronic balance, a second frame connected to the fixing seat and a second electronic balance fixed to the second frame, the fixing frame and the The portion in contact with the molten dripping material to be tested is made of a heat-insulating material. The molten dripping material to be tested is in the form of a rectangular parallelepiped with its front end in contact with the air. The angle adjuster is used to adjust the angle of the fixing frame relative to the horizontal plane. The first electronic balance is used to measure the mass change rate of the molten dripping material to be tested. The second electronic balance is used to measure the mass change rate of the molten droplets of the molten dripping material to be tested. The numerical simulation results and the actual results both include the spatiotemporal distribution of the back temperature of the molten dripping material, the mass change rate of the molten dripping material, and the mass change rate of the molten droplets.

[0092] A comparison module, configured to compare the numerical simulation result with the actual result;

[0093] If the error between the numerical simulation result and the actual result is lower than the preset error range, it indicates that the accuracy of the target analysis model meets expectations.

[0094] It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on the device for analyzing the fire spread mechanism of molten dripping materials. In other embodiments of the present invention, the device for analyzing the fire spread mechanism of molten dripping materials may include more or fewer components than illustrated, or may combine or separate certain components, or employ a different component arrangement. The illustrated components may be implemented in hardware, software, or a combination of both.

[0095] The information interaction, execution process, etc. between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For specific contents, please refer to the description in the embodiment of the method of the present invention and will not be repeated here.

[0096] An embodiment of the present invention further provides an electronic device, comprising: at least one memory and at least one processor;

[0097] The at least one memory is configured to store a machine-readable program;

[0098] The at least one processor is configured to call the machine-readable program to execute the method for analyzing the fire spread mechanism of molten dripping materials in any embodiment of the present invention.

[0099] An embodiment of the present invention also provides an analysis system for the fire spread mechanism of molten dripping materials, including a molten dripping material fire spread parameter measurement device and the electronic equipment as described above, the electronic equipment is used to compare the numerical simulation results with the actual results to verify the target analysis model.

[0100] Embodiments of the present invention further provide a computer-readable medium storing instructions for causing a computer to execute the method for analyzing the fire spread mechanism of molten dripping materials as described herein. Specifically, a method or apparatus can be provided that includes a storage medium storing software program code that implements the functions of any of the aforementioned embodiments, and causes a computer (or CPU or MPU) operating in the method or apparatus to read and execute the program code stored in the storage medium.

[0101] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute part of the present invention.

[0102] Examples of storage media for providing program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, the program code can be downloaded from a server computer via a communication network.

[0103] In addition, it should be clear that the functions of any of the above embodiments can be realized not only by executing the program code read by the computer, but also by completing part or all of the actual operations through operating methods operated on the computer based on instructions of the program code.

[0104] The foregoing description describes specific embodiments of the present invention. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0105] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made on the basis of the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for analyzing the fire spread mechanism of molten dripping materials, characterized in that: include: Selecting a target analysis model in the PFEM software, and inputting solid phase pyrolysis parameters and a viscosity coefficient required for particle motion into the target analysis model; Setting initial conditions for the target analysis model during the fire spread process of molten dripping material; Setting boundary conditions for the target analysis model during the fire spread process of molten dripping material; Using the target analysis model, numerically simulating the fire spread process of the molten dripping material is performed to obtain numerical simulation results of the fire spread of the molten dripping material, so as to analyze the fire spread mechanism of the molten dripping material; The solid-phase pyrolysis parameters are obtained by thermogravimetric analysis, differential scanning calorimetry, micro-combustion calorimetry and controlled atmosphere pyrolysis instrument, and the viscosity coefficient required for particle movement is obtained by rheometer; The solid-phase pyrolysis parameters include reaction kinetic parameters of the pyrolysis of the molten dripping material, reaction thermodynamic parameters of the pyrolysis of the molten dripping material, combustion heat of combustible phase products generated during the pyrolysis reaction of the molten dripping material, and component density and thermal conductivity of the molten dripping material during the pyrolysis reaction; wherein the reaction kinetic parameters include Arrhenius pre-exponential factor, activation energy, stoichiometric coefficient and residual carbon yield, and the reaction thermodynamic parameters include specific heat capacity and heat absorbed or released by the reaction; The thermogravimetric analyzer is used to measure the mass loss data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction kinetic parameters; The differential scanning calorimeter is used to measure the endothermic and exothermic data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction thermodynamic parameters; The micro combustion calorimeter is used to measure the heat release data of the pyrolysis gas phase products of the molten dripping material when they are completely burned in excess oxygen, so as to invert the combustion heat of the combustible phase products; The controlled atmosphere pyrolyzer is used to measure the back temperature, mass data and morphological data of the molten dripping material exposed to radiant heat, and to invert the component density and the thermal conductivity by coupling the reaction kinetic parameters, the reaction thermodynamic parameters and the combustion heat of the combustible gas phase products obtained by inversion.

2. The method according to claim 1, characterized in that The initial conditions of the target analysis model in the molten dripping material fire spread process are set, including: The solid phase temperature, gas phase temperature, and mass fractions of oxygen and pyrolysis products of the molten dripping material are set; when the temperature of the solid-gas interface reaches the preset ignition temperature, the mass fraction of oxygen is set to 0, and the mass fraction of pyrolysis products is set to 1.

3. The method according to claim 1, characterized in that The setting of the boundary conditions of the target analysis model in the molten dripping material fire spread process includes: The gas velocity and temperature gradient of the middle symmetry plane of the molten droplet material along the vertical direction are both set to 0; wherein the solid phase region and the gas phase region are both regarded as rectangular parallelepipeds, the solid phase region is the region of the molten droplet material, and the solid phase region is located in the gas phase region; The simulation of the igniter is simplified to adding a fixed heat flux value to the surface of the molten dripping material; Setting a constant uniform velocity at the bottom inlet of the gas phase region; The relative pressure at the top outlet of the gas phase region was set to 0.

4. The method according to any one of claims 1 to 3, characterized in that After obtaining the numerical simulation results of the fire spread of the molten dripping material, the method further includes: The actual results of the fire spread parameter measurement device for molten dripping materials are obtained; wherein the measurement device includes a molten dripping material to be measured, a fixing frame coated on the molten dripping material to be measured, a thermocouple for measuring the back temperature of the molten dripping material to be measured, an angle adjuster connected to the fixing frame, a first frame connected to the angle adjuster, a first electronic balance supporting the first frame, a fixing seat supporting the first electronic balance, a second frame connected to the fixing seat and a second electronic balance fixed to the second frame, the fixing frame and the molten dripping material to be measured are connected. The portion in contact with the molten dripping material is made of a heat-insulating material. The molten dripping material to be tested is a rectangular parallelepiped with its front end in contact with the air. The angle adjuster is used to adjust the angle of the fixing frame relative to the horizontal plane. The first electronic balance is used to measure the mass change rate of the molten dripping material to be tested. The second electronic balance is used to measure the mass change rate of the molten droplets of the molten dripping material to be tested. The numerical simulation results and the actual results both include the spatiotemporal distribution of the back temperature of the molten dripping material, the mass change rate of the molten dripping material, and the mass change rate of the molten droplets. comparing the numerical simulation results with the actual results; If the error between the numerical simulation result and the actual result is lower than the preset error range, it indicates that the accuracy of the target analysis model meets expectations.

5. An analytical device for the fire spread mechanism of molten dripping materials, characterized in that: include: An input module, used to select a target analysis model in the PFEM software and input solid phase pyrolysis parameters and a viscosity coefficient required for particle motion into the target analysis model; A first setting module is used to set the initial conditions of the target analysis model in the molten dripping material fire spread process; A second setting module is used to set the boundary conditions of the target analysis model during the fire spread process of the molten dripping material; a numerical simulation module, configured to perform a numerical simulation on the fire spread process of the molten dripping material using the target analysis model, obtain a numerical simulation result of the fire spread of the molten dripping material, and analyze the fire spread mechanism of the molten dripping material; The solid-phase pyrolysis parameters are obtained by thermogravimetric analysis, differential scanning calorimetry, micro-combustion calorimetry and controlled atmosphere pyrolysis instrument, and the viscosity coefficient required for particle movement is obtained by rheometer; The solid-phase pyrolysis parameters include reaction kinetic parameters of the pyrolysis of the molten dripping material, reaction thermodynamic parameters of the pyrolysis of the molten dripping material, combustion heat of combustible phase products generated during the pyrolysis reaction of the molten dripping material, and component density and thermal conductivity of the molten dripping material during the pyrolysis reaction; wherein the reaction kinetic parameters include Arrhenius pre-exponential factor, activation energy, stoichiometric coefficient and residual carbon yield, and the reaction thermodynamic parameters include specific heat capacity and heat absorbed or released by the reaction; The thermogravimetric analyzer is used to measure the mass loss data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction kinetic parameters; The differential scanning calorimeter is used to measure the endothermic and exothermic data of the molten dripping material during the pyrolysis reaction to invert and obtain the reaction thermodynamic parameters; The micro combustion calorimeter is used to measure the heat release data of the pyrolysis gas phase products of the molten dripping material when they are completely burned in excess oxygen, so as to invert the combustion heat of the combustible phase products; The controlled atmosphere pyrolyzer is used to measure the back temperature, mass data and morphological data of the molten dripping material exposed to radiant heat, and to invert the component density and the thermal conductivity by coupling the reaction kinetic parameters, the reaction thermodynamic parameters and the combustion heat of the combustible gas phase products obtained by inversion.

6. An electronic device, characterized in that: include: at least one memory and at least one processor; The at least one memory is configured to store a machine-readable program; The at least one processor is configured to call the machine-readable program to execute the method according to claim 4.

7. An analysis system for the fire spread mechanism of molten dripping materials, characterized in that: The device comprises a device for measuring fire spread parameters of molten dripping material and the electronic device according to claim 6, wherein the electronic device is used to compare the numerical simulation result with the actual result to verify the target analysis model.

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