A method and system for assessing the situation of smoke in tunnels

Abstract

This invention discloses a method and system for assessing tunnel smoke conditions, belonging to the field of traffic management technology. The method includes: simulating predicted diffusion data of air pollutants in the current tunnel using the lattice Boltzmann method, which can accurately simulate the diffusion of air pollutants and facilitate subsequent analysis; acquiring environmental parameters of the current tunnel to correct the predicted diffusion data, which can improve the accuracy of the predicted diffusion; simulating the discrete migration behavior of moving units in the tunnel based on cellular automata and two-dimensional grids, which can simulate the behavior of moving units in the tunnel and facilitate the determination of the development of the situation; and establishing a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis, which combines the predicted diffusion data, the environmental parameters, and the discrete migration behavior to output an assessment value, which can numerically describe the changes in the accident situation.

Description

Technical Field

[0001] This invention relates to the field of traffic management technology, and in particular to a method and system for assessing smoke conditions in tunnels. Background Technology

[0002] Highways often traverse mountainous areas, necessitating the construction of tunnels. Due to the unique structure of tunnels, especially long highway tunnels, a fire that breaks out inside can quickly spread and endanger other vehicles that cannot evacuate in time, causing severe casualties and property damage if it is not detected and extinguished promptly. Traditional CFD methods (such as FVM) are computationally inefficient in complex boundary conditions (tunnel slope, ventilation shafts), making it difficult to meet real-time requirements. Empirical models (such as empirical formulas) neglect the coupling effects of turbulence and thermal radiation, resulting in insufficient accuracy. Summary of the Invention

[0003] This invention proposes a method and system for assessing the smoke situation in tunnels, in order to solve the problems of low efficiency and insufficient accuracy in existing methods for calculating and simulating disaster situations in tunnels.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A method for assessing the situation of tunnel smoke includes: simulating predicted diffusion data of air pollutants in the current tunnel based on the lattice Boltzmann method; acquiring environmental parameters of the current tunnel to correct the predicted diffusion data; simulating the discrete migration behavior of moving units within the tunnel based on the cellular automata method and a two-dimensional grid; and establishing a tunnel smoke accident situation assessment model based on the fuzzy hierarchical analysis method to combine the predicted diffusion data, the environmental parameters, and the discrete migration behavior to output an assessment value.

[0006] Furthermore, the environmental parameters include gas concentration, temperature, and wind speed;

[0007] The method of correcting the predicted diffusion data includes correcting the predicted diffusion data based on data assimilation techniques.

[0008] Furthermore, the data used to simulate the predicted diffusion of air pollutants in the current tunnel based on the lattice Boltzmann method includes:

[0009] ;in, For the first Particle distribution function in each direction, For relaxation time, For the equilibrium distribution function, It is a discrete velocity vector.

[0010] Furthermore, the environmental parameters are acquired by sensors correspondingly installed in the tunnel; correspondingly, the method also includes: acquiring the structural parameters of the tunnel and, in conjunction with the sensors, establishing a digital twin environment for the tunnel.

[0011] Furthermore, the simulation of the discrete migration behavior of moving units within the tunnel based on the cellular automata method and two-dimensional mesh includes: propagation rules: ,in, Indicates the first Grid at all times state, Represents its neighborhood state, function The migration probability or propagation rule is defined.

[0012] Furthermore, the establishment of the tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis includes:

[0013] Construct a multi-level evaluation structure for accident situation: top-level overall accident situation assessment; middle-level risk indicator categories; bottom-level specific sub-indicators used to characterize the degree of attribution in risk levels;

[0014] Form a fuzzy membership matrix R, where where the th The first indicator for the first The membership degree of the risk level is , The weights of the indicators are obtained based on hierarchical evaluation;

[0015] Fuzzy synthesis operation generates the overall evaluation vector ;

[0016] Based on the pre-set risk level scores, the overall assessment vector is weighted to obtain the assessment values ​​for different risk levels.

[0017] Furthermore, the establishment of the tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis also includes:

[0018] Based on the predicted diffusion data, the input values ​​for the fuzzy hierarchical analysis method are set;

[0019] Based on the evaluation values, the boundary conditions or grid distribution of the lattice Boltzmann method are automatically adjusted to form an iterative optimization closed loop.

[0020] Furthermore, the weighting process for the overall evaluation vector includes:

[0021] Based on a linear weighted model, the risk level score and the overall assessment vector are processed to obtain the assessment values ​​for different risk levels.

[0022] Furthermore, the sub-index is a fuzzy membership function set through expert judgment and data fusion.

[0023] A tunnel smoke situation assessment system includes:

[0024] The first module is used to simulate the predicted diffusion data of air pollutants in the current tunnel based on the lattice Boltzmann method;

[0025] The second module is used to acquire the current environmental parameters of the tunnel in order to correct the predicted diffusion data;

[0026] The third module is used to simulate the discrete migration behavior of moving units within a tunnel based on the cellular automata method and two-dimensional mesh.

[0027] The fourth module is used to establish a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis, so as to combine the predicted diffusion data, the environmental parameters and the discrete migration behavior to output the assessment value.

[0028] By adopting the above technical solution, the present invention has the following beneficial effects:

[0029] 1. This invention simulates the predicted diffusion data of air pollutants in a current tunnel using the lattice Boltzmann method, which can accurately simulate the diffusion of air pollutants and facilitate subsequent analysis; it obtains the environmental parameters of the current tunnel to correct the predicted diffusion data, which can improve the accuracy of the predicted diffusion; it simulates the discrete migration behavior of moving units in the tunnel based on the cellular automata method and two-dimensional grid, which can simulate the behavior of moving units in the tunnel and facilitate the determination of the development of the situation; it establishes a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis, which combines the predicted diffusion data, the environmental parameters, and the discrete migration behavior to output assessment values, which can numerically describe the changes in the accident situation. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a tunnel smoke situation assessment method proposed in this invention. Detailed Implementation

[0031] 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.

[0032] like Figure 1 The tunnel smoke situation assessment method shown includes:

[0033] S1. Predicted diffusion data of air pollutants in the current tunnel based on the lattice Boltzmann method;

[0034] S2. Obtain the current environmental parameters of the tunnel to correct the predicted diffusion data;

[0035] S3. Based on the cellular automata method and two-dimensional mesh, simulate the discrete migration behavior of moving units within a tunnel;

[0036] S4. Establish a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis to combine the predicted diffusion data, the environmental parameters, and the discrete migration behavior to output assessment values.

[0037] The environmental parameters include gas concentration, temperature, and wind speed;

[0038] The method of correcting the predicted diffusion data includes correcting the predicted diffusion data based on data assimilation techniques.

[0039] The data used to simulate the predicted diffusion of air pollutants in the current tunnel based on the lattice Boltzmann method includes:

[0040] ;in, For the first Particle distribution function in each direction, For relaxation time, For the equilibrium distribution function, It is a discrete velocity vector.

[0041] The environmental parameters are acquired by sensors installed in the tunnel. Correspondingly, the method also includes: acquiring the structural parameters of the tunnel and, in conjunction with the sensors, establishing a digital twin environment for the tunnel.

[0042] The method based on cellular automata and two-dimensional meshes simulates the discrete migration behavior of moving units within a tunnel, including: propagation rules: ,in, Indicates the first Grid at all times state, Represents its neighborhood state, function The migration probability or propagation rule is defined.

[0043] The establishment of a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis includes:

[0044] Construct a multi-level evaluation structure for accident situation: top-level overall accident situation assessment; middle-level risk indicator categories; bottom-level specific sub-indicators used to characterize the degree of attribution in risk levels;

[0045] Form a fuzzy membership matrix R, where where the th The first indicator for the first The membership degree of the risk level is , The weights of the indicators are obtained based on hierarchical evaluation;

[0046] Fuzzy synthesis operation generates the overall evaluation vector ;

[0047] Based on the pre-set risk level scores, the overall assessment vector is weighted to obtain the assessment values ​​for different risk levels.

[0048] The establishment of a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis also includes:

[0049] Based on the predicted diffusion data, the input values ​​for the fuzzy hierarchical analysis method are set;

[0050] Based on the evaluation values, the boundary conditions or grid distribution of the lattice Boltzmann method are automatically adjusted to form an iterative optimization closed loop.

[0051] The weighting process for the overall evaluation vector includes:

[0052] Based on a linear weighted model, the risk level score and the overall assessment vector are processed to obtain the assessment values ​​for different risk levels.

[0053] The sub-indicator is a fuzzy membership function set through expert judgment and data fusion.

[0054] A tunnel smoke situation assessment system includes:

[0055] The first module is used to simulate the predicted diffusion data of air pollutants in the current tunnel based on the lattice Boltzmann method;

[0056] The second module is used to acquire the current environmental parameters of the tunnel in order to correct the predicted diffusion data;

[0057] The third module is used to simulate the discrete migration behavior of moving units within a tunnel based on the cellular automata method and two-dimensional mesh.

[0058] The fourth module is used to establish a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis, so as to combine the predicted diffusion data, the environmental parameters and the discrete migration behavior to output the assessment value.

[0059] Example

[0060] By employing multi-source data fusion technology, a complete data chain for predicting tunnel smoke accidents is constructed by integrating environmental sensors (CO / VI detection).

[0061] Specifically, the lattice Boltzmann method is used to simulate the diffusion process of smoke or pollutants in a tunnel, and its basic evolution equation is expressed as follows:

[0062] ;

[0063] in, Indicates the first Particle distribution function in each direction, For relaxation time, For the equilibrium distribution function, It is a discrete velocity vector.

[0064] A digital twin environment for the tunnel can be set up, allowing for remote and digital description and monitoring of the tunnel. By combining real-time inputs such as CO concentration, temperature, and wind speed, and continuously correcting the predicted values ​​through data assimilation technology, the spatial and temporal variations of smoke concentration distribution in the digital twin environment can be predicted, thereby improving the prediction accuracy in real-world accident scenarios.

[0065] For biological behaviors, discrete migration behaviors such as crowds and vehicle queues can be simulated using a two-dimensional grid based on cellular automata methods. The state of each cell is propagated from its neighbors, and the cell state is updated according to local rules. These propagation rules can be expressed by the following formula: ;in, Indicates the first Grid at all times state, The function represents the neighborhood state. The migration probability or propagation rule is defined (such as the current grid state changing when the neighbor's fire or smoke level exceeds the threshold). By using the lattice Boltzmann method as the core model, the congestion length or smoke diffusion path under the influence of dense crowds can be simulated.

[0066] A quantification module is set up to extract key parameters from the simulation results of the lattice Boltzmann method: average pollutant concentration, ventilation efficiency index, and exposure risk index (based on the spatiotemporal distribution of concentration in areas of human activity).

[0067] When establishing a tunnel smoke accident situation assessment model using the Fuzzy Hierarchical Analysis (FAHP) method, a multi-level evaluation structure for the accident situation is constructed, including a top-level "overall accident situation assessment," a middle-level "risk indicator categories" (such as environmental factors, traffic conditions, and sensor anomaly levels), and a bottom-level multiple specific sub-indicators. Each sub-indicator is assigned a fuzzy membership function through expert judgment and data fusion to characterize its degree of belonging in the "low-medium-high" risk levels.

[0068] This forms a fuzzy membership matrix. , of which The first indicator for the first The membership degree of the risk level is Indicator weights The result is derived from the Analytic Hierarchy Process (AHP), which involves less expert evaluation. Then, fuzzy comprehensive operations are used to generate the overall evaluation vector. :

[0069] ;

[0070] For example, risk levels are divided into three levels (low, medium, and high). The final overall score can be calculated using a weighted average as follows: ;in, These represent low, medium, and high risk levels, respectively. Higher risk levels... The value indicates the higher the level of risk in the corresponding situation.

[0071] In practice, system coupling mechanisms:

[0072] Data interface: Maps the concentration field, ventilation efficiency index, exposure risk index, velocity field, and other data output from the lattice Boltzmann method simulation results to the input indicators of FAHP (fuzzy hierarchical analysis).

[0073] Dynamic feedback: Based on the FAHP evaluation results, the boundary conditions (such as vent parameters) or mesh distribution of LBM (Lattice Boltzmann Method, LBM) are automatically adjusted to form an iterative optimization closed loop.

[0074] Comprehensive evaluation module: Uses a linear weighted model to generate the final evaluation results;

[0075] The purpose / beneficial effects of this plan:

[0076] 1. During tunnel excavation, monitor the emissions and ventilation of construction machinery in real time to predict the potential risk of smoke accumulation.

[0077] 2. Emergency response to smoke during operation: Real-time monitoring and prediction of vehicle exhaust, fire smoke, etc. in operating tunnels, and early activation of emergency response.

[0078] 3. Emergency drills and plan optimization: Simulate different smoke accident scenarios using a digital twin system to optimize emergency plans and evacuation schemes.

[0079] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for assessing the smoke situation in tunnels, characterized in that, include: Predicted diffusion data of air pollutants in the current tunnel were simulated based on the lattice Boltzmann method; Obtain the current environmental parameters of the tunnel to correct the predicted diffusion data; Based on the cellular automata method and two-dimensional mesh, the discrete migration behavior of moving units within a tunnel is simulated. A tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis is established to combine the predicted diffusion data, the environmental parameters, and the discrete migration behavior to output assessment values.

2. The tunnel smoke situation assessment method according to claim 1, characterized in that, The environmental parameters include gas concentration, temperature, and wind speed; The method of correcting the predicted diffusion data includes correcting the predicted diffusion data based on data assimilation techniques.

3. The tunnel smoke situation assessment method according to claim 2, characterized in that, The data used to simulate the predicted diffusion of air pollutants in the current tunnel based on the lattice Boltzmann method includes: ;in, For the first Particle distribution function in each direction, For relaxation time, For the equilibrium distribution function, It is a discrete velocity vector.

4. The tunnel smoke situation assessment method according to claim 3, characterized in that, The method based on cellular automata and two-dimensional meshes, simulating the discrete migration behavior of moving units within a tunnel, includes: Propagation rules: ,in, Indicates the first Grid at all times state, Represents its neighborhood state, function The migration probability or propagation rule is defined.

5. The tunnel smoke situation assessment method according to claim 4, characterized in that, The establishment of a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis includes: Construct a multi-level evaluation structure for accident situation: top-level overall accident situation assessment; middle-level risk indicator categories; bottom-level specific sub-indicators used to characterize the degree of attribution in risk levels; Form a fuzzy membership matrix R, where where the th The first indicator for the first The membership degree of the risk level is , The weights of the indicators are obtained based on hierarchical evaluation; Fuzzy synthesis operation generates the overall evaluation vector ; Based on the pre-set risk level scores, the overall assessment vector is weighted to obtain the assessment values ​​for different risk levels.

6. The tunnel smoke situation assessment method according to claim 5, characterized in that, The establishment of a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis also includes: Based on the predicted diffusion data, the input values ​​for the fuzzy hierarchical analysis method are set; Based on the evaluation values, the boundary conditions or grid distribution of the lattice Boltzmann method are automatically adjusted to form an iterative optimization closed loop.

7. The tunnel smoke situation assessment method according to claim 6, characterized in that, The weighting process for the overall evaluation vector includes: Based on a linear weighted model, the risk level score and the overall assessment vector are processed to obtain the assessment values ​​for different risk levels.

8. The tunnel smoke situation assessment method according to claim 7, characterized in that, The sub-indicator is a fuzzy membership function set through expert judgment and data fusion.

9. The tunnel smoke situation assessment method according to claim 8, characterized in that, The environmental parameters are acquired by sensors installed in the tunnel. Correspondingly, the methods also include: The structural parameters of the tunnel are obtained, and a digital twin environment of the tunnel is established by combining the sensors.

10. A tunnel smoke situation assessment system, characterized in that, include: The first module is used to simulate the predicted diffusion data of air pollutants in the current tunnel based on the lattice Boltzmann method; The second module is used to acquire the current environmental parameters of the tunnel in order to correct the predicted diffusion data; The third module is used to simulate the discrete migration behavior of moving units within a tunnel based on the cellular automata method and two-dimensional mesh. The fourth module is used to establish a tunnel smoke accident situation assessment model based on fuzzy hierarchical analysis, so as to combine the predicted diffusion data, the environmental parameters and the discrete migration behavior to output the assessment value.

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