A hydrogen gas leak safety boundary visualization method and system

Abstract

The present application relates to a kind of hydrogen leakage safety boundary visualization method and system, belong to new energy technology field.First, the same hydrogen leakage process is carried out using hydrogen leakage experimental device and numerical simulation, data fusion is carried out to the measured hydrogen concentration and simulated hydrogen concentration, and fusion concentration is obtained, then contour curve boundary is randomly taken point until the position of the point is equal to 4%, the position of the point is marked as calibration position, the average gray value is obtained by doing time average processing to the gray value of calibration position, finally, all the pixel points with average gray value in hydrogen leakage gray scale image are marked, and the visual boundary of 4% hydrogen concentration is obtained.The present application uses the strategy of data fusion to improve the accuracy of calibration hydrogen leakage safety boundary profile.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a method and system for visualizing the safety boundary of hydrogen leakage. Background Technology

[0002] Hydrogen is a clean, efficient, and renewable energy source with advantages such as zero pollutant emissions and high specific heat capacity. This gives hydrogen fuel cell vehicles a significant advantage in reducing carbon emissions compared to traditional gasoline vehicles. However, the flammable and explosive nature of hydrogen poses safety hazards in its storage and transportation. A mixture of gases within the hydrogen combustion concentration range can ignite upon contact with an open flame, causing very serious consequences. Therefore, in the event of a hydrogen leak, it is crucial to move away from areas of high hydrogen combustion concentration to avoid accidents. However, due to the colorless and odorless nature of hydrogen, leaks are difficult to observe directly, and it is impossible to obtain the profile of the hydrogen combustion limit concentration. Therefore, a method is needed to visualize the hydrogen combustion boundary profile in the event of a leak, indicating the danger zone to ensure the safe use of hydrogen energy and reduce the likelihood of accidents.

[0003] In their paper (High-Pressure Underexpansion Hydrogen Leakage and Diffusion Model and Experimental Study), Xiang Yuxia et al. used numerical simulation and gas infrared thermal imaging visualization techniques to study the leakage and diffusion patterns of hydrogen. They determined the boundary profile of the hydrogen jet by comparing the initial and ejected states of the water vapor cloud through the impact of a hydrogen jet stream on a high-temperature water vapor cloud. However, this visualization method does not consider the influence of the mutual perturbation between the water vapor cloud and the hydrogen jet on the hydrogen jet profile, resulting in only a relatively coarse profile and failing to obtain an accurate and visually clear safety boundary profile.

[0004] Current hydrogen leak detection methods rely solely on sensor measurements. However, these methods are limited by the inherent time delay of the sensors, making it impossible to obtain hydrogen concentration in real time. They also fail to account for measurement errors and do not utilize other effective means to correct the results. Furthermore, the concentration values ​​obtained are calibrated only for a single location, failing to provide a comprehensive description of the hydrogen leak safety boundary. In contrast, simple numerical simulation methods can only simulate hydrogen leaks under ideal conditions, making it difficult to fully simulate the hydrogen leak concentration distribution under real-world disturbances. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for visualizing the safety boundary of hydrogen leakage, which uses a data fusion strategy to improve the accuracy of calibrating the safety boundary profile of hydrogen leakage.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for visualizing the safety boundary of a hydrogen leak includes:

[0008] Construct a hydrogen leakage experimental device;

[0009] An abstract model of the hydrogen leakage experimental device was constructed, and the hydrogen leakage process was simulated to obtain the simulated concentration field when the hydrogen leakage diffusion reached a steady state. In the simulated concentration field, a profile curve with a hydrogen concentration of 4% was determined.

[0010] Hydrogen leakage experiments were conducted using the hydrogen leakage schlieren experimental apparatus. After the hydrogen leakage diffusion reached a steady state, a grayscale image of the hydrogen leakage was acquired. At the same time, points were randomly selected on the boundary of the contour curve, and the hydrogen concentration at the selected points was measured.

[0011] The hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field are fused to obtain the fused concentration at the sampling point.

[0012] If the fusion concentration at the sampling point is not equal to 4%, adjust the sampling point until the fusion concentration at the sampling point is equal to 4%, and record the sampling point at this time as the calibration point.

[0013] Find the gray value corresponding to the calibration position in the grayscale image of hydrogen leakage and perform time-average processing to obtain the average gray value;

[0014] By labeling and connecting all pixels in the hydrogen leak grayscale image whose grayscale value is equal to the average grayscale value, a visible lower boundary contour curve of the hydrogen combustion limit can be obtained.

[0015] Optionally, the hydrogen leakage experimental apparatus includes: a hydrogen cylinder;

[0016] The hydrogen cylinder is used to simulate hydrogen leakage by injecting it into the air at a fixed mass flow rate.

[0017] Optionally, an abstract model is performed on the hydrogen leakage experimental device, and the hydrogen leakage process is simulated to obtain a simulated concentration field when the hydrogen leakage diffusion reaches a steady state. A profile curve for a hydrogen concentration of 4% is then determined within the simulated concentration field, specifically including:

[0018] The hydrogen leakage experimental device was modeled using finite element analysis software, and the hydrogen leakage process was simulated under preset temperature, pressure and mass flow conditions to obtain the simulated concentration field when the hydrogen leakage diffusion reaches steady state.

[0019] A Cartesian coordinate system is established with the center of the hydrogen cylinder nozzle as the origin, the axial direction of the hydrogen cylinder nozzle as the positive x-axis, and the radial upward direction of the hydrogen cylinder nozzle as the positive y-axis.

[0020] The simulated concentration field is represented in a Cartesian coordinate system, and the minimum threshold for displaying hydrogen concentration is set to 4%. The hydrogen combustion limit boundary profile curve with 4% as the lower limit is obtained as the profile curve for a hydrogen concentration of 4%.

[0021] Optionally, the process of fusing the hydrogen concentration measured at the sampling point with the hydrogen concentration at the sampling point in the simulated concentration field to obtain the fused concentration at the sampling point specifically includes:

[0022] Based on the simulated concentration field, calculate the variance of the hydrogen concentration simulation results;

[0023] In the hydrogen leakage experiment, the hydrogen concentration at each point was measured, and the variance of the hydrogen concentration measurement results was calculated.

[0024] Based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results, the confidence weights of the simulation results and the measurement results are determined.

[0025] Based on the hydrogen concentration at the sampling point in the simulated concentration field Hydrogen concentration measured at sampling points Confidence weights of simulation results And the confidence weight of the measurement results Using the formula Calculate the fusion concentration at the sampling point .

[0026] Optionally, determining the confidence weights of the simulation results and the measurement results based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results specifically includes:

[0027] Assuming that both the simulated and measured hydrogen concentration results follow a normal distribution, the formula for calculating the variance of the fusion concentration is determined as follows: In the formula, The variance of the fusion concentration. The variance of the hydrogen concentration simulation results is given. The variance of the hydrogen concentration measurement results;

[0028] Differentiating the formula for calculating the variance of the fusion concentration, we obtain the formula for calculating the confidence weights of the simulation results. ;

[0029] When the variance of the fusion concentration reaches its minimum value, the formula for calculating the confidence weight of the measurement result is as follows: ;

[0030] Based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results, the confidence weight of the simulation results is determined using the formula for calculating the confidence weight of the simulation results, and the confidence weight of the measurement results is determined using the formula for calculating the confidence weight of the measurement results.

[0031] A hydrogen leak safety boundary visualization system includes:

[0032] Experimental setup module, used to build a hydrogen leakage experimental setup;

[0033] The hydrogen leakage simulation module is used to abstractly model the hydrogen leakage experimental device, simulate the hydrogen leakage process, obtain the simulated concentration field when the hydrogen leakage diffusion reaches a steady state, and determine the profile curve of hydrogen concentration equal to 4% in the simulated concentration field.

[0034] The hydrogen leakage experiment module is used to conduct hydrogen leakage experiments using the hydrogen leakage experiment device. After the hydrogen leakage diffusion reaches a steady state, a grayscale image of the hydrogen leakage is obtained using the schlieren method. At the same time, points are randomly selected on the boundary of the contour curve, and the hydrogen concentration at the selected points is measured.

[0035] The fusion module is used to fuse the hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field to obtain the fused concentration at the sampling point.

[0036] The calibration location recording module is used to adjust the sampling location until the fusion concentration at the sampling location is equal to 4% if the fusion concentration at the sampling location is not equal to 4%, and record the sampling location at this time as the calibration location.

[0037] The time-average processing module is used to find the gray value corresponding to the calibration position in the grayscale image of hydrogen leakage and perform time-average processing to obtain the average gray value.

[0038] The connection module is used to mark and connect all pixels in the hydrogen leak grayscale image whose grayscale value is equal to the average grayscale value, so as to obtain a visible lower boundary contour curve of the hydrogen combustion limit.

[0039] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the aforementioned method for visualizing the safety boundary of a hydrogen leak.

[0040] A computer-readable storage medium having a computer program stored thereon, which, when executed, implements the aforementioned method for visualizing the safety boundaries of a hydrogen leak.

[0041] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0042] This invention discloses a method and system for visualizing the safety boundary of a hydrogen leak. First, a hydrogen leak experimental setup and numerical simulation are used to simulate the same hydrogen leak process. The measured hydrogen concentration and the simulated hydrogen concentration are fused to obtain a fused concentration. Then, points are randomly selected on the boundary of the contour curve, and fine-tuned near these points until the selected point equals 4%. This selected point is recorded as the calibration position. The grayscale value of the calibration position is averaged over time to obtain the average grayscale value. Finally, all pixels in the hydrogen leak grayscale image whose grayscale value is the average grayscale value are labeled to obtain the visible boundary of the 4% hydrogen concentration. This invention uses a data fusion strategy to improve the accuracy of calibrating the hydrogen leak safety boundary contour. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 A flowchart of a method for visualizing the safety boundary of hydrogen leakage provided in an embodiment of the present invention;

[0045] Figure 2 A schematic diagram of the hydrogen leakage safety boundary visualization method provided in an embodiment of the present invention;

[0046] Figure 3 A schematic diagram of numerical simulation results provided in an embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of grayscale value calibration provided in an embodiment of the present invention;

[0048] Figure 5 This is a schematic diagram of the safe concentration profile of hydrogen leakage provided in an embodiment of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] The purpose of this invention is to provide a method and system for visualizing the safety boundary of hydrogen leakage, which uses a data fusion strategy to improve the accuracy of calibrating the safety boundary profile of hydrogen leakage.

[0051] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] For hydrogen leakage scenarios, the purpose of this invention is to comprehensively utilize numerical simulation information, sensor information, and grayscale information, and based on a data fusion strategy, obtain the image grayscale value corresponding to a 4% hydrogen concentration, and then perform time-averaged processing on the grayscale value to calibrate the overall hydrogen flammable boundary contour, finally obtaining a real-time hydrogen leakage grayscale image with flammable boundary annotations.

[0053] This invention provides a method for visualizing the safety boundary of a hydrogen leak, such as... Figure 1 and Figure 2 As shown, it includes the following steps:

[0054] Step S1: Construct a hydrogen leakage experimental device.

[0055] A hydrogen leakage experimental device was built using the schlieren method. The experiment will simulate hydrogen leakage by spraying a high-pressure hydrogen cylinder into the air at a fixed mass flow rate, while a high-speed camera will be used to film the leakage process.

[0056] Step S2: Abstract model the hydrogen leakage experimental device and simulate the hydrogen leakage process to obtain the simulated concentration field when the hydrogen leakage diffusion reaches a steady state, and determine the profile curve of hydrogen concentration equal to 4% in the simulated concentration field.

[0057] In the finite element software, the experimental setup in the first step is abstractly modeled. The same temperature and pressure conditions as in the experimental setup are set. After setting the mass flow rate of hydrogen outflow, the calculation is performed to obtain the concentration field distribution when hydrogen diffusion reaches steady state. The profile curve of hydrogen concentration equal to 4% in the concentration field is defined as f(x).

[0058] The confidence weight of the numerical simulation can also be calculated based on the variance of the numerical simulation results. .

[0059] For example, the specific process of step S2 is as follows:

[0060] During modeling, the left boundary was defined as the incident boundary, divided into upper and lower sections, which were set as the air inlet and hydrogen inlet respectively. The remaining boundaries were set as pressure outlets to simulate the process of hydrogen leakage into the air. Numerical simulation calculations were performed on the model to obtain the concentration field distribution under steady-state diffusion. The calculation was repeated after refining the mesh until the number of meshes no longer had a significant impact on the calculation results. The mesh independence was verified, and the concentration field when hydrogen leakage reached steady state was obtained.

[0061] Establish a plane rectangular coordinate system with the center of the nozzle as the origin, the axial direction of the nozzle as the positive x-axis, and the radial upward direction of the nozzle as the positive y-axis;

[0062] By setting the minimum concentration display threshold to 4%, the hydrogen combustion limit boundary profile with a lower limit of 4% is obtained. The boundary profile function y=f(x) can be obtained from the profile curve, where x is the abscissa of each point on the profile in a Cartesian coordinate system, y is the ordinate of each point on the profile in a Cartesian coordinate system, and f is the mapping relationship between the abscissa and ordinate of each point on the profile. Assuming that the numerical simulation results follow a normal distribution, the confidence weight of the numerical simulation results can be calculated based on the variance of the numerical simulation results. .

[0063] Step S3: Conduct a hydrogen leakage experiment using a hydrogen leakage experimental apparatus. After the hydrogen leakage diffusion reaches a steady state, acquire a grayscale image of the hydrogen leakage. At the same time, randomly select points on the boundary of the contour curve and measure the hydrogen concentration at the selected points.

[0064] A hydrogen leakage experiment was conducted. A grayscale image of the hydrogen leakage was obtained using the schlieren method. Random sampling points were taken on the leakage curve from the f(x) curve obtained in step S2 using a hydrogen sensor. Simulated concentrations were obtained from the simulated concentration field in step S2. The measured concentration is obtained based on the sensor readings. .

[0065] Step S4: The hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field are fused to obtain the fused concentration at the sampling point.

[0066] Define fusion concentration The meaning of fusion concentration is that it is a result that is closer to the actual concentration value by combining the numerical simulation results and the sensor measurement results according to their confidence weights. It can be considered that the fusion concentration is closer to the real concentration value than the simulated concentration and the measured concentration.

[0067] Step S4 specifically includes the following processes:

[0068] Images of hydrogen leaks were captured using schlieren imaging, and the fusion concentration at randomly selected points was defined. ,in This is the calculated fusion concentration value for this point. For simulated concentration Credibility weights, To measure concentration Credibility weights, and Should meet: .

[0069] The specific method for determining the confidence weights is as follows: It is assumed that both the numerical simulation results and the sensor measurement results follow a normal distribution, i.e.:

[0070]

[0071] in Indicates a normal distribution. , The simulated concentrations are respectively The mean and variance, , The concentrations were measured respectively. The mean and variance of , then The variance can be expressed as:

[0072]

[0073] Applying both sides of the equation Differentiation shows that when:

[0074] The variance has a minimum value, which can be considered as the minimum uncertainty of the fusion concentration. At this point:

[0075] Step S5: If the fusion concentration at the sampling point is not equal to 4%, adjust the sampling point until the fusion concentration at the sampling point is equal to 4%, and record the sampling point at this time as the calibration point.

[0076] Adjust the sampling point until the fusion concentration is achieved. It equals 4%, and the position at this time is recorded as the calibration position P(x,y).

[0077] Step S6: Find the gray value corresponding to the calibration position in the hydrogen leakage grayscale image and perform time-average processing to obtain the average grayscale value.

[0078] By analyzing the grayscale image of the hydrogen leak, the grayscale value corresponding to point P(x,y) in the grayscale image is found, and the average grayscale value is obtained by performing time-average processing on this grayscale value. Establish the average gray value The calibration relationship with a 4% hydrogen concentration.

[0079] Step S7: Mark and connect all pixels in the hydrogen leakage grayscale image whose grayscale value is equal to the average grayscale value to obtain a visible lower boundary contour curve of the hydrogen combustion limit.

[0080] In a grayscale image, all grayscale values ​​are... There is a one-to-one correspondence between the pixels and the hydrogen concentration of 4%. All grayscale values... The pixels are labeled to obtain a visible contour curve, which can be used for safety warnings.

[0081] This invention provides a method for visualizing the safety boundary of hydrogen leakage. It utilizes the schlieren method to construct a hydrogen leakage experimental device. The experimental device is then modeled and calculated in finite element software to obtain the hydrogen concentration field distribution when the hydrogen leakage diffusion reaches a steady state. The profile curve representing a 4% hydrogen concentration in this field is defined as f(x). The reliability weight of the numerical simulation is calculated based on the variance of the numerical simulation results. This is used to characterize the reliability of the numerical simulation results; a hydrogen leakage experiment is conducted, and a grayscale image of the hydrogen leakage is obtained using the schlieren method. A hydrogen sensor is used to randomly select points on the obtained f(x) curve for measurement, and the concentration value corresponding to that point in the simulated concentration field obtained from the numerical simulation is defined as the simulated concentration. The concentration obtained from the actual sampling point measurement is recorded as the measured concentration. The confidence weight of the sensor measurement is obtained by calculating the variance of the sensor measurement. This is used to characterize the reliability of sensor measurement results, through the formula... Calculate the fusion concentration at the actual measurement sampling location. The value can be considered as the true concentration value at the sampling point being closer to the concentration obtained from the numerical simulation and the concentration measured by the sensor, each multiplied by its respective confidence weight and then added together, i.e., the fused concentration. Fine-tune the sensor sampling position until it reaches this position. The value is equal to 4%, and the location of the sampling point at this time is denoted as the calibration position P(x, y); the gray value at position P(x, y) is then subjected to time-averaged processing to obtain the gray value. All grayscale values ​​in the grayscale image The points were marked to obtain the visible boundary of the 4% hydrogen concentration.

[0082] In an environment with a temperature of 293 K and a pressure of 1 atmosphere, the mass flow rate of air is set to 0.006 kg / s, and the mass flow rate of hydrogen at the inlet is... Using kg / s as a specific condition, we will illustrate the method for visualizing the safety boundary of hydrogen leakage.

[0083] The solution was obtained using Fluent software. A second-order upwind difference scheme was used for the convection terms in the momentum and energy equations. The hydrogen concentration field at steady state was obtained, with a minimum display threshold of 4% for hydrogen concentration. The resulting concentration field distribution is shown below. Figure 3 As shown, a Cartesian coordinate system is established with the center point of the outlet as the origin. The curve profile with the outermost hydrogen concentration of 4% is denoted as f(x). The variance of the numerical simulation results is calculated, and the confidence weight of the simulation results is calculated based on the variance.

[0084] After obtaining the simulated concentration field, a hydrogen leakage experiment was conducted under the same operating conditions, controlling the same hydrogen mass flow rate. Once the hydrogen leakage reached a steady state, a high-speed camera was used to film the hydrogen leakage process. A hydrogen concentration sensor was used to randomly select points on f(x) for measurement, and the concentration value at the corresponding location in the simulated concentration field was recorded as the simulated concentration. The concentration value actually measured by the sensor is the measured concentration. Based on the variance of the hydrogen concentration sensor, the reliability weight of the measured value is calculated. Then, the fusion concentration at that point is... That is, the simulated concentration at that point. and concentration measurement The concentration value is obtained by multiplying each sample by its respective confidence weight and then summing the results. If this concentration value is not equal to 4%, then fine-tuning is performed at the original sampling location until the desired concentration is achieved. Equal to 4%, the sampling position at this point is defined as the calibration position, and the horizontal and vertical coordinates of this point in the established coordinate system are recorded. Based on these coordinates, the corresponding pixel in the grayscale image is found, and the grayscale value at that pixel is obtained by time-averaging. This establishes the grayscale value. The correspondence between this and the minimum combustion concentration of hydrogen (4%) is as follows: Figure 4 As shown.

[0085] Establish grayscale values After establishing the correspondence between 4% and 4%, all grayscale values ​​in the grayscale image are... The pixels are labeled to obtain the visible lower boundary contour curve of the flammability limit, such as... Figure 5 As shown, it can be used for security early warning.

[0086] This invention provides a method for visualizing the safety boundary of hydrogen leakage, which has the following advantages:

[0087] 1. This invention is the first to adopt a data fusion strategy in the problem of visualizing the safety boundary of hydrogen leakage. It comprehensively utilizes the results of numerical simulation and sensor measurement, which makes up for the shortcomings of numerical simulation in fully simulating the real situation and the disadvantages of the delay in sensor measurement of gas concentration. This improves the accuracy of calibrating the safety boundary profile of hydrogen leakage and the results are reliable.

[0088] 2. This invention is the first to link concentration values ​​with grayscale values ​​in schlieren, which theoretically allows for the reconstruction of contours for any concentration value. Applied to the field of hydrogen safety early warning, it can visualize safety boundaries when a hydrogen leak occurs, providing a direct reference for preventing danger.

[0089] 3. This invention is applicable to various working conditions and is not limited to hydrogen leakage situations. As long as the calibrated correspondence between grayscale values ​​and concentrations is obtained, the corresponding concentration profile can be visualized.

[0090] 4. This invention uses a data fusion-based visualization method for hydrogen leakage safety boundaries. Compared with traditional visualization methods, it has high accuracy and can achieve real-time display. Compared with laser-induced fluorescence (LIF) technology, it reduces costs, simplifies the usage method, and increases the possibility of utilization.

[0091] This invention also provides a hydrogen leak safety boundary visualization system, comprising:

[0092] Experimental setup module, used to build a hydrogen leakage experimental setup;

[0093] The hydrogen leakage simulation module is used to abstractly model the hydrogen leakage experimental device, simulate the hydrogen leakage process, obtain the simulated concentration field when the hydrogen leakage diffusion reaches a steady state, and determine the profile curve of hydrogen concentration equal to 4% in the simulated concentration field.

[0094] The hydrogen leakage experiment module is used to conduct hydrogen leakage experiments using a hydrogen leakage experiment device. After the hydrogen leakage diffusion reaches a steady state, a grayscale image of the hydrogen leakage is acquired. At the same time, points are randomly selected on the boundary of the contour curve to measure the hydrogen concentration at the selected points.

[0095] The fusion module is used to fuse the hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field to obtain the fused concentration at the sampling point.

[0096] The calibration location recording module is used to adjust the sampling location until the fusion concentration at the sampling location is equal to 4% if the fusion concentration at the sampling location is not equal to 4%, and record the sampling location at this time as the calibration location.

[0097] The time-average processing module is used to find the gray value corresponding to the calibration position in the grayscale image of hydrogen leakage and perform time-average processing to obtain the average gray value.

[0098] The connection module is used to mark and connect all pixels in the hydrogen leak grayscale image whose grayscale value is equal to the average grayscale value, so as to obtain a visible lower boundary contour curve of the hydrogen combustion limit.

[0099] The hydrogen leakage safety boundary visualization system provided in this embodiment of the invention has a similar working principle and beneficial effects to the hydrogen leakage safety boundary visualization method in the above embodiments, so it will not be described in detail here. For details, please refer to the introduction of the above method embodiments.

[0100] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the aforementioned method for visualizing the safety boundary of a hydrogen leak.

[0101] Furthermore, when the computer program in the aforementioned memory is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory, random access memory, magnetic disks, or optical disks.

[0102] Furthermore, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the aforementioned method for visualizing the safety boundary of a hydrogen leak.

[0103] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0104] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for visualizing the safety boundary of a hydrogen leak, characterized in that, include: Construct a hydrogen leakage experimental device; An abstract model of the hydrogen leakage experimental device was constructed, and the hydrogen leakage process was simulated to obtain the simulated concentration field when the hydrogen leakage diffusion reached a steady state. In the simulated concentration field, a profile curve with a hydrogen concentration of 4% was determined. A hydrogen leakage experiment was conducted using the aforementioned hydrogen leakage experimental apparatus. After the hydrogen leakage diffusion reached a steady state, a grayscale image of the hydrogen leakage was acquired. At the same time, points were randomly selected on the boundary of the contour curve, and the hydrogen concentration at the selected points was measured. The hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field are fused to obtain the fused concentration at the sampling point. If the fusion concentration at the sampling point is not equal to 4%, adjust the sampling point until the fusion concentration at the sampling point is equal to 4%, and record the sampling point at this time as the calibration point. Find the gray value corresponding to the calibration position in the grayscale image of hydrogen leakage and perform time-average processing to obtain the average gray value; By labeling and connecting all pixels in the hydrogen leak grayscale image whose grayscale value is equal to the average grayscale value, a visible lower boundary contour curve of the hydrogen combustion limit can be obtained.

2. The method for visualizing the safety boundary of hydrogen leakage according to claim 1, characterized in that, The hydrogen leakage experimental apparatus includes: a hydrogen cylinder; The hydrogen cylinder is used to simulate hydrogen leakage by injecting it into the air at a fixed mass flow rate.

3. The method for visualizing the safety boundary of hydrogen leakage according to claim 2, characterized in that, An abstract model of the hydrogen leakage experimental device was constructed, and the hydrogen leakage process was simulated to obtain the simulated concentration field when the hydrogen leakage diffusion reached a steady state. A profile curve for a hydrogen concentration of 4% was determined within the simulated concentration field, specifically including: The hydrogen leakage experimental device was modeled using finite element analysis software, and the hydrogen leakage process was simulated under preset temperature, pressure and mass flow conditions to obtain the simulated concentration field when the hydrogen leakage diffusion reaches steady state. A Cartesian coordinate system is established with the center of the hydrogen cylinder nozzle as the origin, the axial direction of the hydrogen cylinder nozzle as the positive x-axis, and the radial upward direction of the hydrogen cylinder nozzle as the positive y-axis. The simulated concentration field is represented in a Cartesian coordinate system, and the minimum threshold for displaying hydrogen concentration is set to 4%. The hydrogen combustion limit boundary profile curve with 4% as the lower limit is obtained as the profile curve for a hydrogen concentration of 4%.

4. The method for visualizing the safety boundary of hydrogen leakage according to claim 1, characterized in that, The process of fusing the hydrogen concentration measured at the sampling point with the hydrogen concentration at the sampling point in the simulated concentration field to obtain the fused concentration at the sampling point specifically includes: Based on the simulated concentration field, calculate the variance of the hydrogen concentration simulation results; In the hydrogen leakage experiment, the hydrogen concentration at each point was measured, and the variance of the hydrogen concentration measurement results was calculated. Based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results, the confidence weights of the simulation results and the measurement results are determined. Based on the hydrogen concentration at the sampling point in the simulated concentration field Hydrogen concentration measured at sampling points Confidence weights of simulation results And the confidence weight of the measurement results Using the formula Calculate the fusion concentration at the sampling point .

5. The method for visualizing the safety boundary of hydrogen leakage according to claim 4, characterized in that, The step of determining the confidence weights of the simulation results and the measurement results based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results specifically includes: Assuming that both the simulated and measured hydrogen concentration results follow a normal distribution, the formula for calculating the variance of the fusion concentration is determined as follows: In the formula, The variance of the fusion concentration. The variance of the hydrogen concentration simulation results is given. The variance of the hydrogen concentration measurement results; Differentiating the formula for calculating the variance of the fusion concentration, we obtain the formula for calculating the confidence weights of the simulation results. ; When the variance of the fusion concentration reaches its minimum value, the formula for calculating the confidence weight of the measurement result is as follows: ; Based on the variance of the hydrogen concentration simulation results and the variance of the hydrogen concentration measurement results, the confidence weight of the simulation results is determined using the formula for calculating the confidence weight of the simulation results, and the confidence weight of the measurement results is determined using the formula for calculating the confidence weight of the measurement results.

6. A hydrogen leak safety boundary visualization system, characterized in that, include: Experimental setup module, used to build a hydrogen leakage experimental setup; The hydrogen leakage simulation module is used to abstractly model the hydrogen leakage experimental device, simulate the hydrogen leakage process, obtain the simulated concentration field when the hydrogen leakage diffusion reaches a steady state, and determine the profile curve of hydrogen concentration equal to 4% in the simulated concentration field. The hydrogen leakage experiment module is used to conduct hydrogen leakage experiments using the hydrogen leakage experiment device. After the hydrogen leakage diffusion reaches a steady state, a grayscale image of the hydrogen leakage is acquired. At the same time, points are randomly selected on the boundary of the contour curve, and the hydrogen concentration at the selected points is measured. The fusion module is used to fuse the hydrogen concentration measured at the sampling point and the hydrogen concentration at the sampling point in the simulated concentration field to obtain the fused concentration at the sampling point. The calibration location recording module is used to adjust the sampling location until the fusion concentration at the sampling location is equal to 4% if the fusion concentration at the sampling location is not equal to 4%, and record the sampling location at this time as the calibration location. The time-average processing module is used to find the gray value corresponding to the calibration position in the grayscale image of hydrogen leakage and perform time-average processing to obtain the average gray value. The connection module is used to mark and connect all pixels in the hydrogen leak grayscale image whose grayscale value is equal to the average grayscale value, so as to obtain a visible lower boundary contour curve of the hydrogen combustion limit.

7. An electronic device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the hydrogen leak safety boundary visualization method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed, implements the hydrogen leak safety boundary visualization method as described in any one of claims 1 to 5.

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