Method, device and equipment for evaluating burning safety of composite material wound high-pressure gas cylinder

Abstract

The invention discloses a method, a device and equipment for evaluating the burning safety of a composite material wound high-pressure gas cylinder, relates to the technical field of safety evaluation of high-pressure gas cylinders, and is used for effectively evaluating the failure risk of the composite material wound high-pressure gas cylinder in a burning environment. Comprising the steps of performing flow field analysis on fire source heat flow input to obtain a flow field analysis result; carrying out a high-temperature test on the composite material and the metal lining, and determining constitutive model parameters related to the temperature; establishing a heat-force coupling analysis model based on the flow field analysis result, the constitutive model parameters and the defined transient heat-force load borne by the high-pressure gas cylinder; verifying and correcting the thermal-mechanical coupling analysis model through a burning test; if the high-pressure gas cylinder is damaged, a fluid-solid coupling analysis model is established in combination with a bisection method, the burning safety of the composite material wound high-pressure gas cylinder is evaluated, and the failure risk of the composite material wound high-pressure gas cylinder in the burning environment can be accurately evaluated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of safety evaluation of high-pressure gas cylinders, and particularly relates to a fire safety evaluation method, device and equipment for a composite-wound high-pressure gas cylinder. BACKGROUND

[0002] With the wide application of high-pressure gas cylinders in the fields of hydrogen storage and gas storage, composite-wound metal-liner high-pressure gas cylinders have become an important type of pressure vessels. The composite-wound metal-liner high-pressure gas cylinders have the advantages of light weight and high strength, but have poor fire resistance and are more likely to degrade in performance and fail in structure under extreme conditions such as high temperature and fire, which poses a serious safety hazard. Therefore, it is an urgent need in current engineering applications to evaluate the safety of composite-wound high-pressure gas cylinders under fire conditions, especially the thermal stress response and rupture behavior of the high-pressure gas cylinders in the process of high-temperature fire.

[0003] Under fire conditions, the external thermal load borne by the high-pressure gas cylinder can cause thermal stress, mechanical property degradation and internal pressure rise of the material, thereby affecting the overall safety of the high-pressure gas cylinder.

[0004] Therefore, in order to effectively evaluate the failure risk of the composite-wound high-pressure gas cylinder under fire conditions, it is necessary to provide a thermal-mechanical coupling numerical method capable of comprehensively analyzing the overall safety of the high-pressure gas cylinder under fire conditions. SUMMARY

[0005] The present application aims to provide a fire safety evaluation method, device and equipment for a composite-wound high-pressure gas cylinder, which can effectively evaluate the failure risk of the composite-wound high-pressure gas cylinder under fire conditions, comprehensively analyze the overall safety of the high-pressure gas cylinder under fire conditions, not only determine whether the high-pressure gas cylinder is damaged, but also provide key parameters such as the pressure relief curve, fragment size and kinetic energy after damage, and provide a scientific basis for the evaluation and optimization of the fire resistance of the high-pressure gas cylinder.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] In a first aspect, the present application provides a fire safety evaluation method for a composite-wound high-pressure gas cylinder, which comprises:

[0008] performing flow field analysis on the heat flow input of the fire source to obtain flow field analysis results, wherein the flow field analysis results at least include the temperature field distribution and pressure field change of the composite-wound high-pressure gas cylinder under fire load;

[0009] conducting high-temperature tests on the composite material and the metal liner to determine temperature-dependent constitutive model parameters;

[0010] establish a thermal-mechanical coupling analysis model based on the flow field analysis result, the constitutive model parameter, and the defined transient thermal-mechanical load borne by the high-pressure gas cylinder; the thermal-mechanical coupling analysis model is used to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder under the fire condition;

[0011] verify and correct the thermal-mechanical coupling analysis model through the fire test; if the high-pressure gas cylinder is damaged, establish a fluid-solid coupling analysis model in combination with the bisection method to evaluate the fire safety of the composite-wound high-pressure gas cylinder.

[0012] Optionally, the flow field analysis is performed on the fire heat input to obtain the flow field analysis result, including:

[0013] The flow field analysis is performed on the fire heat input to calculate the heat exchange between the flame and the surface of the high-pressure gas cylinder, and the temperature field distribution and pressure field variation of the composite-wound high-pressure gas cylinder under the fire load are obtained; the flow field analysis means that the heat exchange process between the fire source and the high-pressure gas cylinder is simulated by using a computational fluid dynamics model; at least the temperature factor, the distance factor, and the flame stability factor of the fire source are considered in the simulation.

[0014] Optionally, the thermal-mechanical coupling analysis model is established based on the flow field analysis result, the constitutive model parameter, and the defined transient thermal-mechanical load borne by the high-pressure gas cylinder, including:

[0015] The thermal-mechanical coupling analysis in the loading process is simplified through discretization processing without considering the influence of the loading history; the composite material is a brittle material and does not produce plastic deformation in the loading process.

[0016] Based on the flow field analysis result, the temperature field obtained through the flow field analysis is functionally fitted, the transient thermal load is defined in the thermal-mechanical coupling analysis in a functional manner, the thermal-mechanical coupling analysis model is established, and the thermal response and mechanical behavior of the high-pressure gas cylinder under the fire condition are simulated.

[0017] Optionally, the thermal-mechanical coupling analysis model is verified and corrected through the fire test; if the high-pressure gas cylinder is damaged, a fluid-solid coupling analysis model is established in combination with the bisection method to evaluate the fire safety of the composite-wound high-pressure gas cylinder, including:

[0018] If the high-pressure gas cylinder is damaged, the temperature field and internal pressure of the damage of the high-pressure gas cylinder are determined in combination with the bisection method, a fluid-solid coupling analysis model is established, and safety evaluation data of the high-pressure gas cylinder are analyzed; the safety evaluation data of the high-pressure gas cylinder at least include the pressure relief curve, the fragment size, and the kinetic energy of the high-pressure gas cylinder.

[0019] Based on the damage evaluation in combination with the test data and the numerical simulation result, the damage critical condition of the composite-wound high-pressure gas cylinder under the fire load is provided, and the damage critical condition at least includes a safety index, and the safety index at least includes a temperature threshold, an internal pressure threshold, and structural integrity.

[0020] Optionally, high-temperature tests of the composite material and the metal liner are carried out to determine temperature-related constitutive model parameters, including:

[0021] Based on the high-temperature tests, experimental data are set, the form of the constitutive model is determined, material thermal performance tests are carried out under high-temperature conditions, and temperature-related constitutive model parameters of the composite material and the metal liner are obtained.

[0022] Optionally, the fluid-structure coupling analysis model simulates the dynamic response of the composite-wound high-pressure gas cylinder under the fire-burning condition by coupling the thermal-mechanical analysis result and the flow field analysis result, and evaluates the damage resistance of the high-pressure gas cylinder under different fire-burning intensities; the safety evaluation data further include simulation results of a rupture mode, fragment scattering and a high-pressure gas cylinder pressure relief process of the composite-wound high-pressure gas cylinder during the fire-burning process.

[0023] Optionally, based on the flow field analysis result, the constitutive model parameters and the defined transient thermal-mechanical load borne by the high-pressure gas cylinder, a thermal-mechanical coupling analysis model is established, including:

[0024] The flow field analysis result is introduced into the structural thermal analysis, and the high-pressure gas cylinder is segmented along the fire-burning direction according to the temperature distribution characteristics;

[0025] A segmented function is used to fit the temperature spatial distribution relationship of each segment to construct a continuous temperature boundary condition input;

[0026] Based on the temperature boundary condition input, a thermal-mechanical coupling analysis model is established in a preset program.

[0027] Compared with the prior art, the composite-wound high-pressure gas cylinder fire-burning safety evaluation method provided by the present application can accurately evaluate the failure risk of the composite-wound high-pressure gas cylinder under the fire-burning environment, can accurately simulate the damage behavior of the high-pressure gas cylinder under the fire-burning condition, and can provide reliable basis for design optimization, material selection and fire safety performance analysis of the high-pressure gas cylinder.

[0028] In a second aspect, the present application provides a composite-wound high-pressure gas cylinder fire-burning safety evaluation device, which comprises:

[0029] a flow field analysis module configured to perform flow field analysis on the heat flux input of the fire source to obtain a flow field analysis result, wherein the flow field analysis result at least includes temperature field distribution and pressure field variation of the composite-wound high-pressure gas cylinder under the fire load;

[0030] a constitutive model parameter determination module configured to perform high-temperature test on the composite material and the metal liner to determine temperature-dependent constitutive model parameters;

[0031] a thermal-mechanical coupling analysis model construction module configured to construct a thermal-mechanical coupling analysis model based on the flow field analysis result, the constitutive model parameters, and the defined transient thermal-mechanical load of the high-pressure gas cylinder, wherein the thermal-mechanical coupling analysis model is used to simulate thermal response and mechanical behavior of the high-pressure gas cylinder under the fire condition;

[0032] a safety evaluation module configured to verify and correct the thermal-mechanical coupling analysis model through the fire test, and to establish a fluid-structure coupling analysis model in combination with the bisection method to evaluate the fire safety of the composite-wound high-pressure gas cylinder if the high-pressure gas cylinder is damaged.

[0033] In a third aspect, the present application provides a composite-wound high-pressure gas cylinder fire safety evaluation device, which comprises:

[0034] a memory, a processor, and a communication interface coupled to the processor, wherein the memory stores a computer program executable by the processor, and the processor executes the computer program to perform the composite-wound high-pressure gas cylinder fire safety evaluation method.

[0035] In a fourth aspect, the present application provides a computer storage medium, wherein the computer storage medium stores instructions, and the instructions are executed to implement the composite-wound high-pressure gas cylinder fire safety evaluation method.

[0036] The device scheme of the second aspect, the equipment scheme of the third aspect, and the computer storage medium scheme of the fourth aspect achieve the same technical effects as the method scheme of the first aspect, and thus will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0037] The accompanying drawings, which are included to provide a further understanding of the present application, form a part of the present application and illustrate embodiments of the present application and together with the description serve to explain the present application. In the drawings:

[0038] Figure 1 a flow chart of the composite-wound high-pressure gas cylinder fire safety evaluation method provided by the present application;

[0039] Figure 2A flowchart of a whole process of a fire safety evaluation method for a composite material wound high-pressure gas cylinder of an embodiment of the present application is shown in the figure.

[0040] Figure 3 A schematic diagram of a function fitting method for defining a temperature field in an embodiment of the present application is shown in the figure.

[0041] Figure 4 A schematic diagram of the discretization of a loading process and the application of a bisection method in an embodiment of the present application is shown in the figure.

[0042] Figure 5 A schematic diagram of a fluid-structure coupling analysis model in an embodiment of the present application is shown in the figure.

[0043] Figure 6 A structure schematic diagram of a fire safety evaluation device for a composite material wound high-pressure gas cylinder provided by the present application is shown in the figure.

[0044] Figure 7 A structure schematic diagram of a fire safety evaluation device for a composite material wound high-pressure gas cylinder is shown in the figure. DETAILED DESCRIPTION

[0045] In order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, the terms of "first", "second", etc. are used to distinguish the same or similar items with basically the same function and effect. For example, the first threshold and the second threshold are only used to distinguish different thresholds, and do not limit the order. Those skilled in the art can understand that the terms of "first", "second", etc. do not limit the quantity and execution order, and the terms of "first", "second", etc. also do not necessarily mean different.

[0046] It should be noted that in the present application, the words "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design presented as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or advantageous than other embodiments or design solutions. Rather, the use of the words "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0047] In this invention, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c, where a, b, and c can be single or multiple.

[0048] To effectively assess the failure risk of composite-wound high-pressure gas cylinders under fire conditions, this invention proposes a thermo-mechanical coupling numerical method, specifically a safety assessment method for composite-wound high-pressure gas cylinders under fire conditions. This method aims to provide an accurate assessment of the failure risk of high-pressure gas cylinders under fire conditions by combining thermo-mechanical coupling numerical simulation with fire testing, for use in the design optimization and safety analysis of high-pressure gas cylinders. It can comprehensively analyze the overall safety of high-pressure gas cylinders under fire conditions. This method can not only determine whether the high-pressure gas cylinder has been damaged, but also provide key parameters such as the pressure relief curve, fragment size, and kinetic energy after damage, providing a scientific basis for the evaluation and optimization of the fire resistance performance of high-pressure gas cylinders.

[0049] Next, the solutions provided in the embodiments of this specification will be described in conjunction with the accompanying drawings:

[0050] like Figure 1 As shown, the process may include the following steps:

[0051] Step 110: Perform flow field analysis on the heat input from the fire source to obtain the flow field analysis results.

[0052] The flow field analysis results include at least the temperature field distribution and pressure field changes of the composite material wrapped around the high-pressure gas cylinder under fire load; specifically, the flow field analysis involves analyzing the heat flow input from the fire source, calculating the heat exchange between the flame and the surface of the high-pressure gas cylinder, and obtaining the temperature field distribution and pressure field changes of the composite material wrapped around the high-pressure gas cylinder under fire load.

[0053] The flow field analysis simulates the heat exchange process between the ignition source and the high-pressure gas cylinder using a computational fluid dynamics (CFD) model, taking into account factors such as the temperature of the ignition source, distance, and flame stability.

[0054] Step 120: Conduct high-temperature tests on composite materials and metal linings to determine temperature-related constitutive model parameters;

[0055] Specifically, based on high-temperature tests, experimental data are set, constitutive model form is determined, and thermal performance tests of materials are conducted under high-temperature conditions to obtain constitutive model parameters related to the temperature of composite materials and metal linings.

[0056] Constitutive models are mathematical models used to describe the mechanical behavior of materials under different stress and strain states. Constitutive model parameters include those found in mathematical models describing the mechanical behavior of materials under different stress, strain, and temperature states, such as elastic modulus, yield strength, and coefficient of thermal expansion.

[0057] Step 130: Based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical load on the high-pressure gas cylinder, establish a thermo-mechanical coupling analysis model.

[0058] The thermo-mechanical coupling analysis model is based on a constitutive model related to material temperature, including the influence of temperature on thermal parameters and mechanical properties.

[0059] The thermo-mechanical coupling analysis model is used to simulate the thermal response and mechanical behavior of high-pressure gas cylinders under fire conditions.

[0060] Discretization of the loading process: Since composite materials are brittle materials, no plastic deformation occurs during loading. Therefore, the influence of loading history is ignored, and the thermo-mechanical coupling analysis during loading is simplified by discretization.

[0061] Thermo-mechanical coupling analysis: Based on the flow field analysis results, the transient thermo-mechanical load on the high-pressure gas cylinder is defined, and a thermo-mechanical coupling analysis model is established to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder under fire conditions.

[0062] Step 140: Verify and correct the thermo-mechanical coupling analysis model through a fire test; if the high-pressure gas cylinder is damaged, establish a fluid-structure coupling analysis model using the dichotomy method to assess the fire safety of the composite material-wound high-pressure gas cylinder.

[0063] Model validation: The thermo-mechanical coupling analysis model was validated and corrected through fire tests;

[0064] Damage assessment: If the high-pressure gas cylinder is damaged, the temperature field and internal pressure of the high-pressure gas cylinder damage are obtained by combining the dichotomy method, a fluid-structure interaction analysis model is established, and the pressure relief curve, fragment size, kinetic energy, etc. of the high-pressure gas cylinder are analyzed to provide corresponding safety assessment data.

[0065] Specifically, the damage assessment method ignores the influence of loading history on the loading result. It calculates the temperature field and internal pressure at the moment of rupture of the high-pressure gas cylinder by discretization and combining the bisection method. The damage assessment combines experimental data and numerical simulation results to provide the critical failure conditions of composite material wrapped high-pressure gas cylinder under fire load, including safety indicators such as temperature threshold, internal pressure threshold and structural integrity.

[0066] The fluid-structure interaction analysis model accurately simulates the dynamic response of composite material-wound high-pressure gas cylinders under fire conditions by coupling the results of thermo-mechanical analysis and flow field analysis, and evaluates its resistance to damage under different fire intensities.

[0067] Safety assessment data can include simulation results of the rupture mode, fragmentation, and depressurization process of high-pressure gas cylinders wrapped with composite materials during fire, which can serve as a basis for improving the safety and optimizing the design of high-pressure gas cylinders.

[0068] Figure 1 The method described herein involves analyzing the flow field of the heat input from the fire source to obtain the flow field analysis results; conducting high-temperature tests on composite materials and metal linings to determine the temperature-related constitutive model parameters; establishing a thermo-mechanical coupling analysis model based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical load on the high-pressure cylinder; verifying and correcting the thermo-mechanical coupling analysis model through fire tests; and, if the high-pressure cylinder fails, establishing a fluid-structure interaction analysis model using the bisection method to assess the fire safety of composite material-wound high-pressure cylinders. This method can accurately assess the failure risk of composite material-wound high-pressure cylinders under fire conditions, accurately simulate the destructive behavior of high-pressure cylinders under fire conditions, and provide a reliable basis for the design optimization, material selection, and fire safety performance analysis of high-pressure cylinders.

[0069] based on Figure 1 In addition to the method described herein, this specification also provides some specific implementation methods of this method, which will be described below.

[0070] Furthermore, the overall process of the composite material winding high-pressure gas cylinder fire safety assessment method of this invention is as follows: Figure 2 As shown, the specific process of the composite material wound high-pressure gas cylinder fire safety assessment method is as follows:

[0071] First, flow field analysis is performed, specifically: the heat flow input of the high-pressure gas cylinder is evaluated through flow field analysis, and the temperature field distribution and pressure field changes of the composite material wound high-pressure gas cylinder under fire load are obtained.

[0072] Next, a thermo-mechanical coupling analysis will be performed. The specific process of the thermo-mechanical coupling analysis is as follows:

[0073] High-temperature constitutive model of materials (linings, composite materials): Conduct high-temperature tests on composite materials and metal linings to obtain temperature-related constitutive model parameters;

[0074] Discretization of loading process: Considering that composite materials are brittle materials, the influence of plastic deformation is ignored, and the loading process is discretized to simplify the thermo-mechanical coupling analysis process and simulate the high-pressure gas cylinder fire response in a quasi-transient manner for efficient calculation.

[0075] Thermo-mechanical coupling analysis: The temperature field obtained from the flow field analysis is fitted with a function, and transient thermal loads are defined in the thermo-mechanical coupling analysis in a functional manner to simulate the thermal response and mechanical behavior of high-pressure gas cylinders under fire conditions;

[0076] Model validation: Conduct fire tests to validate and revise the thermo-mechanical coupling analysis model;

[0077] Damage assessment (fire damage threshold): If the high-pressure gas cylinder is damaged, the temperature field and pressure of the damage are obtained by combining the dichotomy method, a fluid-structure interaction analysis model is established, and the pressure relief curve, fragment size, kinetic energy, etc. of the high-pressure gas cylinder are analyzed to provide safety assessment data.

[0078] Next, the implementation steps of the method flow of the present invention will be described in detail:

[0079] Combined with appendix Figure 2 The method provided in this embodiment mainly includes two core modules: flow field analysis and thermo-mechanical coupling analysis.

[0080] Flow field analysis and temperature and pressure field acquisition: First, based on the gas ignition source condition, a heat exchange model between the ignition source and the high-pressure gas cylinder is established using Fluent computational fluid dynamics software to obtain the time-domain variation characteristics of the temperature field on the outer wall and the internal pressure of the high-pressure gas cylinder under combustion conditions. This simulation process does not consider the deformation and damage of the high-pressure gas cylinder structure, but only focuses on the heat transfer process.

[0081] In this embodiment, the high-pressure gas cylinder has a spherical structure with an outer diameter of 132 mm, an inner diameter of 127 mm, and a metal lining thickness of 1 mm. The heat source adopts a localized directional heating mode, with the flame pointing towards the center of the sphere. The area of ​​action is located on the outer surface of the spherical shell, and the heat flow covers a portion of the spherical surface, with the loaded area accounting for approximately 1 / 8 of the total spherical surface area. The outer wall of the high-pressure gas cylinder is set as the heat transfer boundary, the ambient air temperature is set to 300 K, a radiation model is enabled in the calculation, the simulation time step is set to 0.1 s, and the total loading time is 600 s.

[0082] High-Temperature Constitutive Model Acquisition: Under fire load, the gas inside the high-pressure cylinder expands, and the structure mainly bears tensile load. To accurately describe the material response, the high-temperature mechanical properties of the metal liner and the composite material were characterized. The stress-strain response of the metal liner material was obtained through quasi-static and dynamic tensile tests at different temperatures, and its temperature-strain rate related constitutive parameters were fitted. In this embodiment, the Johnson-Cook constitutive model can be used to describe the mechanical behavior of the metal liner.

[0083] The composite material uses carbon fiber reinforced resin matrix. The specimens are cut from the wound shell and subjected to tensile tests at different temperatures to obtain the temperature-dependent mechanical behavior response. In this embodiment, a temperature-dependent orthotropic model is used for modeling.

[0084] Temperature field fitting and thermo-mechanical coupling analysis model construction: see appendix Figure 3 To incorporate the flow field analysis results into the structural thermal analysis, the surface temperature distribution characteristics of the high-pressure gas cylinder were considered. Under localized fire, the high-pressure gas cylinder exhibits different temperature distribution characteristics along the fire direction: the temperature is high near the fire source and low further away, with a high temperature gradient region existing between the high-temperature and low-temperature areas. To accurately fit the temperature distribution of the high-pressure gas cylinder, it was segmented along the fire direction according to the temperature distribution characteristics, and a piecewise function (f1, f2…f) was used. n Fit the spatial distribution relationship of temperature in each segment to construct a continuous temperature boundary condition input.

[0085] A thermo-mechanical coupled finite element model is established in the LS-DYNA program. Temperature analysis in LS-DYNA can be calculated using the energy conservation equation (1), while mechanical behavior is calculated using the momentum conservation equation (2). The thermo-mechanical coupling method simultaneously solves both the energy and momentum conservation equations and uses a temperature-dependent material model to reflect the influence of heat on its softening, expansion (equation 3), and other mechanical behaviors. Plastic strain energy is partially converted into heat Φ, affecting the temperature field. In the equations, ρ represents density, u is the displacement vector, σ is the stress vector, and f is the volume force. Here, is the gradient operator, c is the specific heat capacity, T is the temperature, k is the thermal conductivity, Φ is the heat source term, and ε is the coefficient of performance. th α represents thermal strain, and α is the coefficient of thermal expansion.

[0086]

[0087] ε th =αΔT (3)

[0088] The temperature boundary is applied to the outer wall element of the high-pressure gas cylinder using the *BOUNDARY_TEMPERATURE command, while the internal gas pressure is applied as an equivalent surface pressure using the *LOAD_SEGMENT command. Simulation results are compared with fire test data to verify and correct the accuracy of the simulation model.

[0089] Bisection method for searching the critical moment of rupture: see appendix Figure 4Considering the brittle nature of composite material failure, the influence of loading history is ignored in the thermo-mechanical coupling analysis. A bisection method is used to iteratively determine the critical moments for rupture / depressurization of the high-pressure gas cylinder. Firstly, at the initial (t0) and final (t...) moments of the fire... n Apply temperature and pressure boundaries and perform structural analysis; if neither of these conditions is damaged, it is determined that the ignition source conditions will not cause the high-pressure gas cylinder to fail.

[0090] If the high-pressure gas cylinder structure is intact at the initial time (t0), then at the end time (t... n If a disruption occurs, then the midpoint between the two times (t) is taken. n / 2 ) to perform analysis, if at that time (t n / 2 If the high-pressure gas cylinder is damaged, then the midpoint between the previous step when it was not damaged (t) is taken. n / 4 Repeat this process until the adjacent time interval is equal to the flow field calculation output step size Δt (Δt = 0.1s in this embodiment), thereby determining the accurate time point of rupture and extracting the temperature and pressure distribution at that moment.

[0091] Fluid-structure interaction simulation of pressure relief response: see appendix Figure 5 Using the temperature and pressure fields extracted at the moment of rupture as initial conditions, a fluid-structure interaction analysis model is constructed to simulate the dynamic process of pressure relief after the high-pressure gas cylinder ruptures.

[0092] This model considers both the internal high-pressure gas and the external normal-pressure air. In this embodiment, the ALE method is used to simulate the fluid domain motion. The fluid-structure interaction analysis results can provide key safety parameters such as pressure relief curves, structural fragment sizes and kinetic energy, which can be used to assess the explosion risk and consequences of high-pressure gas cylinders under fire conditions.

[0093] The technical solution provided by this invention can achieve at least the following technical effects:

[0094] This invention discloses a method for assessing the fire safety of composite material-wound high-pressure gas cylinders, aiming to provide a systematic and precise assessment approach. This method combines flow field analysis, fire testing, and thermo-mechanical coupling simulation to evaluate the response of composite material-wound metal-lined high-pressure gas cylinders under fire loads. The specific steps are as follows: First, flow field analysis is used to assess the heat flow input around the high-pressure gas cylinder, obtaining the temperature field distribution and pressure field changes of the composite material-wound high-pressure gas cylinder under fire loads. Then, high-temperature tests are conducted to obtain the constitutive model parameters of the composite material and the metal liner. Based on the flow field analysis results, a transient thermo-mechanical load is defined, and a thermo-mechanical coupling model is established to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder. The model is verified and corrected through fire testing. If the high-pressure gas cylinder fails, the temperature field and internal pressure of the damage are obtained using a bisection method, and a fluid-structure interaction analysis model is established to analyze the pressure relief curve, fragment size, and kinetic energy after the high-pressure gas cylinder failure, among other safety assessment data. Compared with traditional static testing methods, this invention can accurately simulate the destructive behavior of high-pressure gas cylinders under fire conditions and provide reliable safety assessments. It is applicable to high-pressure gas cylinder design optimization, material selection, and fire safety performance analysis.

[0095] Based on the same idea, this invention also provides a composite material wound high-pressure gas cylinder fire safety assessment device, such as... Figure 6 As shown, the device may include:

[0096] The flow field analysis module 610 is used to perform flow field analysis on the heat flow input from the fire source and obtain the flow field analysis results; the flow field analysis results include at least the temperature field distribution and pressure field changes of the composite material winding high-pressure gas cylinder under fire load.

[0097] Constitutive model parameter determination module 620 is used to conduct high-temperature tests on composite materials and metal linings to determine temperature-related constitutive model parameters.

[0098] Thermo-mechanical coupling analysis model construction module 630 is used to establish a thermo-mechanical coupling analysis model based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical load on the high-pressure gas cylinder; the thermo-mechanical coupling analysis model is used to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder under fire conditions;

[0099] The safety assessment module 640 is used to verify and correct the thermo-mechanical coupling analysis model through fire tests; if the high-pressure gas cylinder is damaged, a fluid-structure coupling analysis model is established by combining the dichotomy method to assess the fire safety of the composite material wound high-pressure gas cylinder.

[0100] based on Figure 6 The device may also include specific implementation units:

[0101] Optionally, the flow field analysis module 610 can be used for:

[0102] A flow field analysis is performed on the heat input from the fire source to calculate the heat exchange between the flame and the surface of the high-pressure gas cylinder, thereby obtaining the temperature field distribution and pressure field changes of the composite material wrapped around the high-pressure gas cylinder under fire load. The flow field analysis means simulating the heat exchange process between the fire source and the high-pressure gas cylinder using a computational fluid dynamics model. The simulation considers at least the temperature factor, distance factor, and flame stability factor of the fire source.

[0103] Optionally, the thermo-mechanical coupling analysis model building module 630 can be used for:

[0104] Ignoring the influence of loading history, the thermo-mechanical coupling analysis during the loading process is simplified through discretization; the composite material is a brittle material and does not undergo plastic deformation during loading.

[0105] Based on the flow field analysis results, the temperature field obtained from the flow field analysis is fitted with a function. The transient thermal load is defined in the thermo-mechanical coupling analysis in a functional manner, and a thermo-mechanical coupling analysis model is established to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder under fire conditions.

[0106] Optionally, the security assessment module 640 can be used for:

[0107] If a high-pressure gas cylinder is damaged, the temperature field and internal pressure of the damage are determined by combining the dichotomy method, a fluid-structure interaction analysis model is established, and the safety assessment data of the high-pressure gas cylinder is analyzed. The safety assessment data of the high-pressure gas cylinder includes at least the pressure relief curve, fragment size, and kinetic energy of the high-pressure gas cylinder.

[0108] Based on damage assessment combined with experimental data and numerical simulation results, the critical failure conditions for composite material winding high-pressure gas cylinders under fire load are provided. The critical failure conditions include at least safety indicators, which include at least temperature threshold, internal pressure threshold and structural integrity.

[0109] Optionally, the constitutive model parameter determination module 620 can be used for:

[0110] Based on high-temperature tests, experimental data were set up, constitutive model form was determined, and thermal performance tests of materials were conducted under high-temperature conditions to obtain constitutive model parameters related to the temperature of composite materials and metal linings.

[0111] Optionally, the fluid-structure interaction analysis model simulates the dynamic response of composite material-wound high-pressure gas cylinders under fire conditions by coupling thermo-mechanical analysis results with flow field analysis results, and evaluates the resistance of high-pressure gas cylinders to damage under different fire intensities; the safety assessment data also includes simulation results of the rupture mode, fragment dispersion, and high-pressure gas cylinder depressurization process of composite material-wound high-pressure gas cylinders during fire.

[0112] Optionally, the thermo-mechanical coupling analysis model building module 630 can be used for:

[0113] The flow field analysis results were incorporated into the structural thermal analysis, and the high-pressure gas cylinder was divided into segments along the burning direction according to the temperature distribution characteristics.

[0114] A piecewise function is used to fit the spatial distribution relationship of the temperature in each segment, thus constructing a continuous temperature boundary condition input.

[0115] A thermo-mechanical coupling analysis model is established in a preset program based on temperature boundary condition input.

[0116] Based on the same approach, this specification also provides an embodiment of a composite material wound high-pressure gas cylinder fire safety assessment device. For example... Figure 7 As shown, the device includes:

[0117] The system includes a memory, a processor, and a communication interface coupled to the processor; the memory stores a computer program that can be run by the processor; when the processor runs the computer program, it executes the aforementioned method for assessing the fire safety of composite material-wound high-pressure gas cylinders.

[0118] like Figure 7 As shown, the processor described above can be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of the program of the present invention. The communication interface described above can be one or more. The communication interface can use any transceiver-like device for communicating with other devices or communication networks.

[0119] like Figure 7 As shown, the terminal device described above may also include a communication line. The communication line may include a path for transmitting information between the components described above.

[0120] Optional, such as Figure 7 As shown, the terminal device may further include a memory. The memory stores a computer program that can be executed by the processor; when the processor executes the computer program, it implements the method provided in the embodiments of the present invention.

[0121] like Figure 7As shown, the memory can be read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, random access memory (RAM) or other types of dynamic storage devices capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed discs, laser discs, optical discs, digital universal discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited to these. The memory can exist independently and be connected to the processor via communication lines. The memory can also be integrated with the processor.

[0122] Optionally, the computer execution instructions in the embodiments of the present invention may also be referred to as application code, and the embodiments of the present invention do not specifically limit this.

[0123] In a specific implementation, as one example, such as Figure 7 As shown, a processor may include one or more CPUs, such as Figure 7 CPU0 and CPU1 in the CPU.

[0124] In a specific implementation, as one example, such as Figure 7 As shown, the terminal device may include multiple processors, such as ​ The processors in the system. Each of these processors can be a single-core processor or a multi-core processor.

[0125] Based on the same idea, this specification also provides a computer storage medium corresponding to the above embodiments. The computer storage medium stores instructions that, when executed, implement the methods in the above embodiments.

[0126] The foregoing mainly describes the solutions provided by the embodiments of the present invention from the perspective of the interaction between various modules. It is understood that each module, in order to achieve the above functions, includes corresponding hardware structures and / or software units for executing each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the various examples described in the embodiments disclosed herein, the present invention can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0127] The embodiments of the present invention can divide functional modules according to the above method examples. For example, each function can be divided into its own functional module, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware or as a software functional module. It should be noted that the module division in the embodiments of the present invention is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.

[0128] The processor described in this specification may also function as a memory. The memory stores computer execution instructions for carrying out the present invention, and its execution is controlled by the processor. The processor executes the computer execution instructions stored in the memory, thereby implementing the method provided in the embodiments of the present invention.

[0129] The memory can be read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, random access memory (RAM) or other types of dynamic storage devices capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed discs, laser discs, optical discs, universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited to these. The memory can exist independently and be connected to the processor via communication lines. The memory can also be integrated with the processor.

[0130] Optionally, the computer execution instructions in the embodiments of the present invention may also be referred to as application code, and the embodiments of the present invention do not specifically limit this.

[0131] The methods disclosed in the above embodiments of the present invention can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above methods can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an ASIC, a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of the present invention can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0132] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

[0133] Although the invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made therein without departing from the spirit and scope of the invention. Accordingly, this specification and drawings are merely exemplary descriptions of the invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if such modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include such modifications and modifications.

Claims

1. A method for assessing the fire safety of composite material wound high-pressure gas cylinders, characterized in that, The methods include: Flow field analysis was performed on the heat input from the heat source to obtain the flow field analysis results; The flow field analysis results include at least the temperature field distribution and pressure field changes of the composite material wound high-pressure gas cylinder under fire load; High-temperature tests were conducted on composite materials and metal linings to determine temperature-dependent constitutive model parameters; Based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical load on the high-pressure gas cylinder, a thermo-mechanical coupling analysis model is established. The thermo-mechanical coupling analysis model is used to simulate the thermal response and mechanical behavior of high-pressure gas cylinders under fire conditions. The thermo-mechanical coupling analysis model was verified and corrected through fire tests. If the high-pressure gas cylinder is damaged, a fluid-structure coupling analysis model was established using the dichotomy method to assess the fire safety of composite material-wound high-pressure gas cylinders.

2. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 1, characterized in that, Flow field analysis was performed on the heat input from the heat source, and the results of the flow field analysis were obtained, including: A flow field analysis is performed on the heat input from the fire source to calculate the heat exchange between the flame and the surface of the high-pressure gas cylinder, thereby obtaining the temperature field distribution and pressure field changes of the composite material wrapped around the high-pressure gas cylinder under fire load. The flow field analysis means simulating the heat exchange process between the fire source and the high-pressure gas cylinder using a computational fluid dynamics model. The simulation considers at least the temperature factor, distance factor, and flame stability factor of the fire source.

3. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 1, characterized in that, Based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical loads on the high-pressure gas cylinder, a thermo-mechanical coupling analysis model is established, including: Ignoring the influence of loading history, the thermo-mechanical coupling analysis during the loading process is simplified through discretization; the composite material is a brittle material and does not undergo plastic deformation during loading. Based on the flow field analysis results, the temperature field obtained from the flow field analysis is fitted with a function. The transient thermal load is defined in the thermo-mechanical coupling analysis in a functional manner, and a thermo-mechanical coupling analysis model is established to simulate the thermal response and mechanical behavior of the high-pressure gas cylinder under fire conditions.

4. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 1, characterized in that, The thermo-mechanical coupling analysis model was verified and corrected through fire tests. If a high-pressure gas cylinder is damaged, a fluid-structure interaction analysis model is established using the dichotomy method to assess the fire safety of composite material-wound high-pressure gas cylinders, including: If a high-pressure gas cylinder is damaged, the temperature field and internal pressure of the damage are determined by combining the dichotomy method, a fluid-structure interaction analysis model is established, and the safety assessment data of the high-pressure gas cylinder is analyzed. The safety assessment data of the high-pressure gas cylinder includes at least the pressure relief curve, fragment size, and kinetic energy of the high-pressure gas cylinder. Based on damage assessment combined with experimental data and numerical simulation results, the critical failure conditions for composite material winding high-pressure gas cylinders under fire load are provided. The critical failure conditions include at least safety indicators, which include at least temperature threshold, internal pressure threshold and structural integrity.

5. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 1, characterized in that, High-temperature tests were conducted on composite materials and metal linings to determine temperature-dependent constitutive model parameters, including: Based on high-temperature tests, experimental data were set up, constitutive model form was determined, and thermal performance tests of materials were conducted under high-temperature conditions to obtain constitutive model parameters related to the temperature of composite materials and metal linings.

6. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 4, characterized in that, The fluid-structure interaction analysis model simulates the dynamic response of composite material-wound high-pressure gas cylinders under fire conditions by coupling thermo-mechanical analysis results with flow field analysis results, and evaluates the resistance of high-pressure gas cylinders to damage under different fire intensities; the safety assessment data also includes simulation results of the rupture mode, fragment dispersion, and high-pressure gas cylinder depressurization process of composite material-wound high-pressure gas cylinders during fire.

7. The method for assessing the fire safety of composite material wound high-pressure gas cylinders according to claim 3, characterized in that, Based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical loads on the high-pressure gas cylinder, a thermo-mechanical coupling analysis model is established, including: The flow field analysis results were incorporated into the structural thermal analysis, and the high-pressure gas cylinder was divided into segments along the burning direction according to the temperature distribution characteristics. A piecewise function is used to fit the spatial distribution relationship of the temperature in each segment, thus constructing a continuous temperature boundary condition input. A thermo-mechanical coupling analysis model is established in a preset program based on temperature boundary condition input.

8. A composite material-wound high-pressure gas cylinder fire safety assessment device, characterized in that, The device includes: The flow field analysis module is used to perform flow field analysis on the heat flux input from the fire source and obtain the flow field analysis results. The flow field analysis results include at least the temperature field distribution and pressure field changes of the composite material wound high-pressure gas cylinder under fire load; The constitutive model parameter determination module is used to conduct high-temperature tests on composite materials and metal liners to determine temperature-related constitutive model parameters. The thermo-mechanical coupling analysis model construction module is used to establish a thermo-mechanical coupling analysis model based on the flow field analysis results, constitutive model parameters, and the defined transient thermo-mechanical loads on the high-pressure gas cylinder; The thermo-mechanical coupling analysis model is used to simulate the thermal response and mechanical behavior of high-pressure gas cylinders under fire conditions. A safety assessment module is used to verify and correct the thermo-mechanical coupling analysis model through fire tests. If a high-pressure gas cylinder is damaged, a fluid-structure interaction analysis model can be established using the dichotomy method to assess the fire safety of composite material-wrapped high-pressure gas cylinders.

9. A fire safety assessment device for high-pressure gas cylinders wound with composite materials, characterized in that the device... include: Memory, processor, and communication interface coupled to the processor; The memory stores computer programs that can be executed by the processor; When the processor runs the computer program, it executes the fire safety assessment method for composite material winding high-pressure gas cylinders as described in any one of claims 1 to 7.

10. A computer storage medium, characterized in that, The computer storage medium stores instructions that, when executed by the processor, implement the composite material winding high-pressure gas cylinder fire safety assessment method according to any one of claims 1 to 7.

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