Dangerous chemical accident analysis system and analysis method based on digital twinning

Abstract

The invention discloses a dangerous chemical accident analysis system and analysis method based on digital twinning. The method comprises the following steps: establishing a jet fire accident consequence model of a fire spread analysis unit; establishing a toxic gas leakage accident consequence model; establishing a pool fire accident consequence model; establishing a steam cloud explosion accident consequence model; setting coordinates, proportion and position attributes of the model in the process of importing the three-dimensional data of the chemical industry park; sensor real-time monitoring data are accessed through a data interface and serve as input parameters, and dynamic updating and visual effect display are achieved. Three-dimensional scene restoration under high resolution is realized through a digital twin technology, model influence parameters are interactively set in combination with a Web end interface, physical states and environmental factors of hazardous chemicals are monitored in real time, and dynamic simulation and analysis are performed through a digital twin model, so that early recognition and early warning of accident risks are realized. And the prevention and coping capability of dangerous chemical accidents is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hazardous chemicals safety management and control, and specifically to a hazardous chemicals accident analysis system and analysis method based on digital twins. Background Art

[0002] The entire life cycle of hazardous chemicals includes production, operation, storage, transportation, use and disposal. There is a risk of accidents at each stage. In recent years, with the rapid development of the chemical industry, accidents involving hazardous chemicals have occurred frequently, causing huge casualties and economic losses, seriously affecting the high-quality development of the economy and social stability.

[0003] Through the study of existing hazardous chemical accident analysis methods, it is found that most inventions lack real-time and predictive capabilities, and are unable to simulate the disaster effects after an accident, making it difficult to conduct effective early warning and prevention before an accident occurs. In addition, traditional accident analysis methods often rely on experience and qualitative judgments, and lack precise quantitative analysis capabilities.

[0004] In order to improve the prevention and response capabilities of hazardous chemical accidents and to display more accurate and high-definition three-dimensional effect models, it is necessary to develop a method for analyzing hazardous chemical accidents based on digital twins. This method should be able to use technologies such as the Internet of Things, big data, and artificial intelligence to monitor the physical state and environmental factors of hazardous chemicals in real time, and dynamically simulate and analyze them through digital twin models, so as to achieve early identification and early warning of accident risks. Summary of the invention

[0005] In order to solve the problems raised in the above background technology, the present invention provides a hazardous chemicals accident analysis system and analysis method based on digital twins.

[0006] A hazardous chemicals accident analysis system based on digital twins, including:

[0007] Fire spread analysis unit: used to simulate the trend of fire spread according to parameter settings;

[0008] Gas leakage analysis unit: Based on the positioning of the gas leakage source and the Gaussian plume diffusion model, the gas diffusion under different leakage source strengths, wind speeds and wind directions is simulated to simulate the three-dimensional unsteady turbulent flow process of gas diffusion;

[0009] Pool fire analysis unit: used to simulate, evaluate and analyze the severity and danger level of pool fire accident consequences and the scope of disaster impact;

[0010] Steam cloud analysis unit: used to simulate the process of steam cloud explosion after tank leakage, use TNT equivalent method to estimate the severity of steam cloud explosion, consider a certain percentage of steam participating in the explosion to form shock wave, analyze the destructive effect of shock wave, and analyze the impact range;

[0011] Digital twin visualization accident simulation unit: used to build a virtual model corresponding to the production, storage and transportation of hazardous chemicals in real scenarios, simulate the development effects of hazardous chemical accidents, and evaluate the impact of accidents on personnel, equipment and the environment through monitoring and data analysis.

[0012] The method for analyzing hazardous chemical accidents based on digital twins of the present invention comprises the following steps:

[0013] Step S1: Establishing a jet fire accident consequence model of a fire spread analysis unit;

[0014] Step S2: Establish a toxic gas leakage accident consequence model;

[0015] Step S3: Establishing a pool fire accident consequence model;

[0016] Step S4: Establishing a steam cloud explosion accident consequence model;

[0017] Step S5: In the process of importing the three-dimensional data of the chemical park, the coordinates, scale and position attributes of the model are set; the real-time monitoring data of the sensor is accessed through the data interface as an input parameter to achieve dynamic update and visualization effect display.

[0018] The present invention uses digital twin technology to achieve three-dimensional scene restoration under high resolution, and combines the interactive setting of model influencing parameters with the Web interface to conduct real-time monitoring of the physical state and environmental factors of hazardous chemicals, and performs dynamic simulation and analysis through the digital twin model, thereby achieving early identification and early warning of accident risks and improving the prevention and response capabilities of hazardous chemical accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of the hazardous chemicals accident analysis method based on digital twins of the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] A hazardous chemicals accident analysis system based on digital twins, including:

[0022] Fire spread analysis unit: used to simulate the trend of fire spread according to parameter settings;

[0023] Gas leakage analysis unit: Based on the positioning of the gas leakage source and the Gaussian plume diffusion model, the gas diffusion under different leakage source strengths, wind speeds and wind directions is simulated to simulate the three-dimensional unsteady turbulent flow process of gas diffusion;

[0024] Pool fire analysis unit: used to simulate, evaluate and analyze the severity and danger level of pool fire accident consequences and the scope of disaster impact;

[0025] Steam cloud analysis unit: used to simulate the process of steam cloud explosion after tank leakage, use TNT equivalent method to estimate the severity of steam cloud explosion, consider a certain percentage of steam participating in the explosion to form shock wave, analyze the destructive effect of shock wave, and analyze the impact range;

[0026] Digital twin visualization accident simulation unit: used to build a virtual model corresponding to the production, storage and transportation of hazardous chemicals in real scenarios, simulate the development effects of hazardous chemical accidents, and evaluate the impact of accidents on personnel, equipment and the environment through monitoring and data analysis.

[0027] The method for analyzing hazardous chemical accidents based on digital twins of the present invention comprises the following steps:

[0028] Step S1: Establishing a jet fire accident consequence model of a fire spread analysis unit;

[0029] Step S2: Establish a toxic gas leakage accident consequence model;

[0030] Step S3: Establishing a pool fire accident consequence model;

[0031] Step S4: Establishing a steam cloud explosion accident consequence model;

[0032] Step S5: In the process of importing the three-dimensional data of the chemical park, the coordinates, scale and position attributes of the model are set; the real-time monitoring data of the sensor is accessed through the data interface as an input parameter to achieve dynamic update and visualization effect display.

[0033] In order to more clearly explain and illustrate the technical solution and implementation of the present invention, several preferred specific embodiments for implementing the technical solution of the present invention are introduced below. Specific embodiment 1

[0035] Fire spread analysis unit: When the combustible material of the pressurized hazardous chemicals leaks, a jet is formed. If it is ignited at the leaking crack, a jet fire is formed. Assume that the flame is conical and is represented by a point source model from the leak to 4 / 5 of the flame length. The jet fire accident consequence model algorithm specifically includes the following steps:

[0036] S11 flame length calculation:

[0037] The flame length equation for a jet fire is: Where L1 is the flame length (m), H c is the heat of combustion (J / kg), and m is the mass flow rate (kg / s).

[0038] S12 thermal radiation flux calculation:

[0039] The equation for the thermal radiation flux received at a distance of X(m) from the flame point source is: Where q is the thermal radiation flux received at a distance X from the flame power source (kw / m 2 ), f is the thermal emissivity, τ is the atmospheric transmission rate, and τ = 1-0.0565lnX. Specific embodiment 2

[0041] Gas leakage analysis unit: Pressure gas leakage usually occurs in the form of jets. The leakage speed is related to the state of its flow. Its characteristics can be described by critical flow (maximum outlet velocity equal to the speed of sound) or subcritical flow. The algorithm of the toxic gas leakage accident consequence model specifically includes the following steps:

[0042] S21 flow state calculation:

[0043] When When it is established, the gas flow is sonic flow; when the formula When it is established, the gas flow is subsonic. In the formula, P0 is the ambient atmospheric pressure (Pa), P is the container pressure (Pa), and k is the adiabatic index of the gas, that is, the constant pressure specific heat C p and constant volume specific heat C v Ratio.

[0044] S22 Critical flow or subcritical flow judgment criteria describe the leakage diffusion rate:

[0045] For many gases, the critical ratio (P / P0) is approximately 2, that is, the storage pressure is approximately equal to twice the atmospheric pressure, and the outlet velocity of the fluid leakage is approximately equal to the speed of sound.

[0046] The gas leakage rate of critical flow can be calculated as According to this formula, when the gas flows at subsonic speed, the leakage is: Where Q is the gas leakage rate (kg / s), C dis the sparse gas leakage, A is the crack area (m 2 ), M is the relative molecular mass of the gas, and R is the universal gas constant (8.31436 J mol -1 K -1 ), T is the storage temperature of the gas (K), Y is the gas expansion factor, the formula is:

[0047] The above considerations are for the irreversible adiabatic diffusion of an ideal gas. In addition, the change in gas leakage rate over time is not considered, so using the initial storage conditions will inevitably lead to conservative results. Specific embodiment 3

[0049] Pool Fire Analysis Unit: The pool fire accident consequence model algorithm mainly calculates the geometric dimensions and radiation parameters of the pool fire flame, and specifically includes the following steps:

[0050] S31 calculation pool diameter:

[0051] According to the amount of leaked liquid and the properties of the ground, S = W / (H min ×ρ) can calculate the maximum possible pool area. Where S is the liquid pool area (m 2 ), W is the mass of the leaked liquid (kg), ρ is the density of the liquid (kg / m 3 ), H min is the minimum oil layer thickness (m). The corresponding relationship between the minimum material layer thickness and ground properties is shown in Table 1.

[0052] Table 1 Thickness of ground materials with different properties

[0053]

[0054]

[0055] S32 Determine Pool Flame Height:

[0056] Formula for calculating pool flame height: Where: L2 is the pool flame height (m), D is the pool diameter (m), m f is the burning rate (kg / m 2 s), ρ0 is the air density (kg / m 3 ), g is the gravitational constant.

[0057] S33 calculates the flame surface heat flux:

[0058] Assuming that the energy is radiated uniformly from the side and top of the cylindrical flame to the surroundings, Calculate the heat flux on the flame surface, where q0 is the heat flux on the pool flame surface (kw / m 2 ), ΔH cis the heat of combustion (kJ / kg), π is the circumference of a circle, f is the thermal radiation coefficient (can be taken as 0.15), m f is the burning rate (kg / m 2 s), and other symbols are the same as before.

[0059] Calculation of the heat flux received by the S34 target:

[0060] The calculation formula of the heat flux q(r) received by the target is: q(r) = q0(1-0.058lnr)V, where q(r) is the heat flux received by the target (kw / m 2 ), q0 is the calculated heat flux on the flame surface (kw / m 2 ), r is the horizontal distance from the target to the center of the oil field (m), and V is the viewing angle coefficient.

[0061] Calculation of S35 viewing angle factor:

[0062] The viewing angle factor V is related to the ratio s of the distance from the target to the vertical axis of the flame to the flame radius, and the ratio h of the flame height to the diameter.

[0063]

[0064] πV H =AB

[0065]

[0066] πV v =tan -1 (h / (s-1)) 0.5 / s+h(JK) / s

[0067]

[0068] K=tan -1 ((s-1) / (s+1)) 0.5

[0069] a=(h 2 +s 2 +1) / (2s)

[0070] b=(1+s 2 ) / (2s)

[0071] Among them, C, D, J, K, V H 、V v It is an intermediate variable introduced for the convenience of description, and π is the ratio of a circle to a circle. Specific embodiment 4

[0073] Steam cloud analysis unit: The shock wave overpressure generated by the steam cloud explosion is its main hazard. The shock wave overpressure can be calculated by the traditional TNT equivalent coefficient method, which equates the explosion energy generated by the accident explosion to a certain equivalent of TNT. The model algorithm specifically includes the following steps:

[0074] S41 determines the flash coefficient:

[0075] Based on thermodynamic data, Estimate the flash vaporization portion of the fuel, where F is the evaporation coefficient and C p is the average specific heat of the fuel (kJ / kgK), ΔT is the temperature difference between the temperature inside the container and the boiling point at ambient pressure (K), and L is the heat of vaporization (kJ / kg).

[0076] S42 calculates the mass of fuel in the cloud:

[0077] W f =2FW,

[0078] Where W f is the mass of fuel in the cloud (kg), W is the mass of leaked fuel (kg), and F is the flash coefficient.

[0079] S43 calculates TNT equivalent:

[0080] W TNT =α e W f H f / H TNT

[0081] Where W TNT is the TNT equivalent of the fuel (kg), W f is the mass of fuel in the cloud (kg), H f is the heat of combustion of the fuel (MJ / kg), H TNT is the explosion heat of TNT (MJ / kg), α e is the TNT equivalent coefficient, recommended α e =0.03.

[0082] S44 converts the actual distance into dimensionless distance:

[0083]

[0084] Where R is the actual distance from the explosion point (m), is the dimensionless distance (m).

[0085] At a distance R from the explosion point, according to the corresponding The overpressure can be calculated and the injuries to personnel and damage to buildings can be predicted. Specific embodiment 5

[0087] A schematic diagram of a hazardous chemicals accident simulation system based on digital twin visualization technology is proposed. Figure 1 As shown:

[0088] S51 prepares 3D data of buildings, equipment, terrain and other elements of the chemical park;

[0089] S52 imports the collected 3D data into the visualization software, setting the coordinates, scale, and position properties of the model during the import process;

[0090] S53 accesses the real-time monitoring data of the sensor through the data interface, which is used as the input parameter of the above model algorithm to realize the dynamic update and visualization effect display of the model;

[0091] S54 also designs an input parameter interface, where users can manually input the influencing parameters of the accident model and observe the model simulation effect in real time;

[0092] S55 displays related data in the form of charts, graphs, animations, etc.

Claims

1. A hazardous chemicals accident analysis system based on digital twins, characterized by include: Fire spread analysis unit: used to simulate the trend of fire spread according to parameter settings; Gas leakage analysis unit: Based on the positioning of the gas leakage source and the Gaussian plume diffusion model, the gas diffusion under different leakage source strengths, wind speeds and wind directions is simulated to simulate the three-dimensional unsteady turbulent flow process of gas diffusion; Pool fire analysis unit: used to simulate, evaluate and analyze the severity and danger level of pool fire accident consequences and the scope of disaster impact; Steam cloud analysis unit: used to simulate the process of steam cloud explosion after tank leakage, use TNT equivalent method to estimate the severity of steam cloud explosion, consider a certain percentage of steam participating in the explosion to form shock wave, analyze the destructive effect of shock wave, and analyze the impact range; Digital twin visualization accident simulation unit: used to build a virtual model corresponding to the production, storage and transportation of hazardous chemicals in real scenarios, simulate the development effects of hazardous chemical accidents, and evaluate the impact of accidents on personnel, equipment and the environment through monitoring and data analysis.

2. The analysis method of the hazardous chemicals accident analysis system based on digital twin according to claim 1 is characterized in that The steps include: Step S1: Establishing a jet fire accident consequence model of a fire spread analysis unit; Step S2: Establish a toxic gas leakage accident consequence model; Step S3: Establishing a pool fire accident consequence model; Step S4: Establishing a steam cloud explosion accident consequence model; Step S5: In the process of importing the three-dimensional data of the chemical park, the coordinates, scale and position attributes of the model are set; the real-time monitoring data of the sensor is accessed through the data interface as an input parameter to achieve dynamic update and visualization effect display.

3. The method for analyzing hazardous chemical accidents based on digital twins according to claim 2 is characterized in that The above step S1 specifically includes the following process: Step S11: flame length calculation: The flame length equation for a jet fire is: Where L1 is the flame length, H c is the heat of combustion, m is the mass flow rate; Step S12: Calculation of thermal radiation flux: The equation for the thermal radiation flux received at a distance X from the flame point source is: Where q is the thermal radiation flux received at a distance X from the flame point source, f is the thermal radiation rate, τ is the atmospheric transmission rate, and τ = 1-0.0565lnX.

4. The method for analyzing hazardous chemical accidents based on digital twins according to claim 3 is characterized in that The above step S2 specifically includes the following process: S21 flow state calculation: When When it is established, the gas flow is sonic flow; when the formula When it is established, the gas flow is subsonic; In the formula, P0 is the ambient atmospheric pressure, P is the container pressure, and k is the adiabatic index of the gas, that is, the constant pressure specific heat C p and constant volume specific heat C v ratio; S22 Critical flow or subcritical flow judgment criteria describe the leakage diffusion rate: The gas leakage rate of critical flow is Calculation, when the gas flows at subsonic speed, the leakage is: Where Q is the gas leakage rate, C d is the gas leakage sparseness, A is the crack area, M is the relative molecular mass of the gas, R is the universal gas constant, T is the storage temperature of the gas, and Y is the gas expansion factor. The formula is:

5. The method for analyzing hazardous chemical accidents based on digital twins according to claim 4 is characterized in that The above step S3 specifically includes the following process: S31 calculation pool diameter: According to the amount of leaked liquid and the properties of the ground, S = W / (H min ×ρ) to calculate the maximum possible pool area; where S is the liquid pool area, W is the mass of the leaked liquid, ρ is the density of the liquid, and H min is the minimum oil layer thickness; S32 Determine Pool Flame Height: Formulas involving pool flame height Where: L2 is the pool flame height, D is the pool diameter, m f is the burning rate, p0 is the air density, and g is the gravitational constant; S33 calculates the flame surface heat flux: Energy is radiated uniformly from the sides and top of the cylindrical flame to the surroundings. Calculate the heat flux on the flame surface, where q0 is the heat flux on the pool flame surface, ΔH c is the heat of combustion, π is the circumference of a circle, f is the thermal radiation coefficient, m f is the burning rate, other symbols are the same as before; Calculation of the heat flux received by the S34 target: The calculation formula of the heat flux q(r) received by the target is: q(r) = q0(1-0.058lnr)V, where q(r) is the heat flux received by the target, q0 is the calculated heat flux on the flame surface, r is the horizontal distance from the target to the center of the oil zone, and V is the viewing angle coefficient; Calculation of S35 viewing angle factor: The viewing angle factor V is related to the ratio of the distance from the target to the vertical axis of the pool flame to the flame radius s, and the ratio of the pool flame height to the pool diameter h; πV H =A-B πV v =tan -1 (h / (s-1)) 0.5 / s+h(J-K) / s K=tan -1 ((s-1) / (s+1)) 0.5 a=(h 2 +s 2 +1) / (2s) b=(1+s 2 ) / (2s) Among them, C, D, J, K, V H 、V v It is an intermediate variable introduced for the convenience of description, and π is the ratio of a circle to a circle.

6. The method for analyzing hazardous chemical accidents based on digital twins according to claim 5 is characterized in that The above step S4 specifically includes the following process: S41 determines the flash coefficient: use Estimate the flash vaporization portion of the fuel, where F is the evaporation coefficient and C p is the average specific heat of the fuel, ΔT is the temperature difference between the temperature in the container and the boiling point at ambient pressure, and L is the heat of vaporization; S42 calculates the mass of fuel in the cloud: IN f =2FW, Where W f is the mass of fuel in the cloud, W is the mass of leaked liquid, and F is the flash coefficient; S43 calculates TNT equivalent: W TNT =α e W f H f / H TNT Where W TNT is the TNT equivalent of the fuel, W f is the mass of fuel in the cloud, H f is the heat of combustion of the fuel, H TNT For the explosive heat of TNT, α e is the TNT equivalent coefficient; S44 converts the actual distance into dimensionless distance: Where R is the actual distance from the explosion point, is the dimensionless distance; at a distance R from the explosion point, according to the corresponding The overpressure can be calculated and the injuries to personnel and damage to buildings can be predicted.

7. The method for analyzing hazardous chemical accidents based on digital twins according to claim 6 is characterized in that The above step S5 specifically includes the following process: S51 prepares 3D data of buildings, equipment, terrain and other elements of the chemical park; S52 imports the collected 3D data into the visualization software, setting the coordinates, scale, and position properties of the model during the import process; S53 accesses the real-time monitoring data of the sensor through the data interface, which is used as the input parameter of the above model algorithm to realize the dynamic update and visualization effect display of the model; S54 also designs an input parameter interface, where users can manually input the influencing parameters of the accident model and observe the model simulation effect in real time; S55 displays related data in the form of charts, graphs, animations, etc.

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