Fireproof channel gas non-return adjusting method and system

Abstract

The invention discloses a fireproof channel gas non-return adjusting method and system, and relates to the technical field of building fire safety and ventilation control, and the method comprises the steps: collecting air pressure, temperature, wind speed and harmful gas concentration data inside and outside a fireproof channel in real time through simulating a building fire and emergency smoke discharge environment; processing the acquired data by using a difference method, a space-time registration method, a moving average method and a normalized weighting method, calculating a countercurrent risk index, a boundary layer wall attachment effect coefficient and a turbulence disturbance coefficient, performing comparative analysis with a preset threshold value, judging whether countercurrent, wall attachment countercurrent and turbulence disturbance risks exist in a channel, and generating a corresponding non-return strategy for an abnormal condition; and after the non-return strategy is implemented, carrying out secondary acquisition, calculating a comprehensive feedback effect index, evaluating the overall effect of the non-return strategy, and if the overall effect is not qualified, carrying out global linkage optimization adjustment. According to the method, real-time monitoring, risk quantitative evaluation and intelligent non-return adjustment of fireproof channel airflow are realized, and the reverse flow risk is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of building fire safety and ventilation control technology, specifically to a method and system for regulating backflow prevention of gas in fire-resistant passages. Background Technology

[0002] Fire escape routes, as vital safety evacuation paths within buildings, play a crucial role in providing a safe environment for evacuation and firefighting during a fire. However, in actual fire scenarios, due to the complex airflow distribution within buildings and the high-temperature smoke generated by the fire source, fire escape routes are highly susceptible to smoke backflow and reverse flow. When reverse flow occurs, smoke, toxic gases, and high-temperature air currents can rapidly enter the fire escape routes, deteriorating the evacuation environment, seriously threatening the lives of personnel, and interfering with firefighting operations.

[0003] In existing building fire protection designs, smoke control systems are typically formed by installing equipment such as ventilation fans, fire dampers, smoke exhaust dampers, regulating valves, constant air volume valves, aluminum alloy air vents, silencers, and plenum chambers to maintain positive pressure in fire-resistant passages and prevent smoke intrusion. However, under complex fire conditions, relying solely on the conventional opening and closing of equipment or fixed airflow control is insufficient to address the backflow risk caused by the coupling of multiple factors, including pressure difference fluctuations, temperature gradient changes, turbulent eddies, and the accumulation of harmful gas concentrations. This is especially true in high-rise buildings, long corridors, or multi-branch fire-resistant passages, where airflow conditions are even more complex, making the prediction and regulation of backflow risks even more challenging.

[0004] The shortcomings of existing technologies are mainly reflected in the following aspects: single monitoring, most systems rely only on pressure or wind speed monitoring, and fail to comprehensively consider multiple physical field factors such as temperature gradient and gas concentration; lack of dynamic judgment mechanism, traditional threshold judgment methods cannot reflect the rapidly changing flow field state under fire conditions in real time, and have lag; crude adjustment method, common methods adjust by opening and closing a single device or increasing or decreasing the air volume, and fail to achieve coordinated optimization control of multiple devices and multiple parameters; lack of closed-loop feedback, existing systems usually lack an effect evaluation mechanism after implementing adjustment measures, and cannot adaptively optimize based on the actual backflow prevention effect. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method and system for regulating gas flow in fire-resistant passages to solve the problems mentioned in the background section.

[0006] To achieve the above objectives, the present invention provides a method for regulating gas flow in fire-resistant passages, comprising the following steps: Step 1: Construct a fire escape test condition under simulated building fire and emergency smoke exhaust environment. Deploy pressure sensors, temperature sensors, wind speed sensors and gas composition sensors inside and outside the fire escape to collect real-time air pressure data, temperature data inside and outside the fire escape, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. Step 2: Process the collected data using differential, spatiotemporal registration, moving average, and normalized weighting methods to obtain the real-time pressure difference between the inside and outside of the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index The backflow risk index RRI is calculated and compared with the backflow risk threshold Rth to determine whether there is backflow risk in the fire escape route. If there is, corresponding strategies are given. Step 3: By collecting wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall adhesion effect coefficient BCI, and compare it with the wall adhesion backflow risk threshold Bth to determine whether there is a risk of wall adhesion backflow in the fire passage. If so, give appropriate strategies. Step 4: Obtain the instantaneous wind speed variance by analyzing the wind speed distribution data within the fire escape route. and cross-sectional average wind speed The turbulence disturbance coefficient TDI is calculated and compared with the turbulence disturbance threshold Tth to determine whether the airflow in the fireproof passage is stable. If it is not stable, corresponding strategies are given. Step 5: After implementing the backflow prevention strategies in Steps 2, 3, and 4, perform a second data collection to calculate the backflow risk index after implementing the backflow prevention strategies. Boundary layer adhesion coefficient and turbulence disturbance coefficient Further calculate the comprehensive feedback effect index (CFEI) and compare it with the comprehensive backflow prevention effect threshold (Cth) to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, give appropriate strategies.

[0007] Preferably, step one includes: S11. Under simulated building fire and emergency smoke exhaust environment, construct fire passage test conditions, and install pressure sensors at both ends and the middle of the fire passage to collect air pressure data on the inside and outside of the fire passage in real time. S12. Temperature sensors are installed at different heights and locations in the fire escape to collect temperature data inside and outside the fire escape simultaneously. S13. Collect wind speed time series data by deploying wind speed sensors at key nodes of fire escape routes; S14. Collect concentration data of carbon monoxide, carbon dioxide and smoke particles through a multi-fireproof channel gas composition sensor.

[0008] Preferably, step two includes: S21. By comparing the air pressure data inside and outside the fire escape route using differential calculation methods, the real-time pressure difference between the two sets of air pressure values ​​is obtained. By collecting temperature data and employing spatiotemporal registration and differential calculation methods, the temperature gradient on both sides of the fire escape route was obtained. The wind speed Vw in fire escape routes was obtained by collecting time-series wind speed data and removing instantaneous fluctuations using a moving average algorithm. A comprehensive hazardous gas concentration index was obtained by collecting concentration data of carbon monoxide, carbon dioxide, and particulate matter using a normalized weighted fusion method. .

[0009] Preferably, step two further includes: S22, By obtaining the real-time pressure difference inside and outside the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index After dimensionless processing, the reverse flow risk index RRI is calculated and obtained. S23. By setting a backflow risk threshold Rth and comparing the backflow risk index RRI with the backflow risk threshold Rth, the first assessment results are obtained, including: When the backflow risk index RRI < backflow risk threshold Rth, it indicates that there is no backflow risk in the fire escape route, and continuous monitoring is required. When the backflow risk index RRI is greater than or equal to the backflow risk threshold Rth, it indicates that there is a backflow risk in the fire passage, triggering the first warning instruction and generating the first strategy: adjust the opening of the fire damper to reduce the cross-sectional area of ​​the fire passage and increase airflow resistance; start the ventilation fan to establish positive pressure airflow inside the fire passage to counteract the backflow trend; and, based on the gas composition monitoring results, link the smoke exhaust valve to quickly discharge high-concentration harmful smoke.

[0010] Preferably, step three includes: S31. By collecting time series data of wind speed at different locations on the cross-section of the fire passage, using a multi-point wind speed sensor array and time series acquisition technology, the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall are extracted, and the data are normalized.

[0011] Preferably, step three further includes: S32. Calculate the boundary layer adhesion coefficient BCI by using the average wind speed Vwall on the treated fire passage wall and the central axial wind speed Vcenter. S33. By setting a pre-defined wall adhesion backflow risk threshold Bth, and comparing the boundary layer wall adhesion effect coefficient BCI with the wall adhesion backflow risk threshold Bth, the second assessment results are obtained, including: When the boundary layer adhesion effect coefficient BCI < the adhesion backflow risk threshold Bth, it indicates that there is no risk of adhesion backflow in the fire passage, the airflow distribution in the fire passage is balanced, and continuous monitoring is required. When the boundary layer adhesion effect coefficient BCI is greater than or equal to the adhesion backflow risk threshold Bth, it indicates that there is an adhesion backflow risk in the fire passage, triggering the second early warning command and generating the second strategy: adjust the air volume distribution of the regulating valve to increase the central airflow energy; link the constant air volume valve to maintain constant air supply in different branches to weaken near-wall backflow; and change the air outlet angle through the aluminum alloy air outlet to guide the airflow to the central area and suppress wall rollback.

[0012] Preferably, step four includes: S41. By analyzing the wind speed distribution data within the fire escape route, the instantaneous wind speed sequence at each measuring point on the key cross-section of the fire escape route is extracted; the instantaneous wind speed variance is obtained using the sliding time window statistical and variance calculation method. The average wind speed of the cross section is obtained by combining the mean filtering algorithm. .

[0013] Preferably, step four further includes: S42. By obtaining the instantaneous wind speed variance and cross-sectional average wind speed After dimensionless processing, the turbulence disturbance coefficient TDI is calculated and obtained; S43. By setting a preset turbulence disturbance threshold Tth, and comparing and analyzing the turbulence disturbance coefficient TDI with the turbulence disturbance threshold Tth, the third evaluation results are obtained, including: When the turbulence disturbance coefficient TDI < turbulence disturbance threshold Tth, it indicates that the airflow in the fireproof passage is stable, there is no risk of backflow, and continuous monitoring is required. When the turbulence disturbance coefficient TDI ≥ turbulence disturbance threshold Tth, it indicates that the airflow in the fire passage is unstable, and there is a risk of local eddies, backflow fire passage formation, and reverse gas entrainment. This triggers the third warning instruction and generates the third strategy: start the ventilation fan to increase the airflow frequency and form a uniform positive pressure zone to weaken the instantaneous impact; use a combination of fire dampers and regulating valves to locally change the airflow organization in the fire passage and break the vortex; use aluminum alloy air outlets to adjust the airflow jet direction and establish airflow barriers at key sections; combine constant air volume valves and static pressure boxes to form a stable air supply pattern and reduce eddies and backflow; and link the smoke exhaust valve to quickly extract the high-temperature smoke entrained by turbulence.

[0014] Preferably, step five includes: S51. After executing the backflow prevention strategy in steps two, three, and four, perform secondary data acquisition to re-acquire the real-time pressure difference inside and outside the fire escape after the backflow prevention strategy is implemented. Temperature gradient on both sides of the fire escape Fire escape route wind speed Comprehensive harmful gas concentration index Average wind speed on fire escape route walls Central axis wind speed Instantaneous wind speed variance and cross-sectional average wind speed Calculate the backflow risk index after the backflow prevention strategy. Boundary layer adhesion coefficient and turbulence disturbance coefficient The values ​​of the reverse flow risk index RRI, boundary layer adhesion effect coefficient BCI, and turbulence disturbance coefficient TDI before the reverse flow prevention strategy were compared. After dimensionless processing, the comprehensive feedback effect index CFEI was calculated. S52. By setting a comprehensive backflow prevention effect threshold Cth, and comparing and analyzing the comprehensive feedback effect index CFEI with the comprehensive backflow prevention effect threshold Cth, the fourth evaluation results are obtained, including: When the comprehensive feedback effect index CFEI is greater than or equal to the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is qualified and should be continuously monitored. When the comprehensive feedback effect index CFEI is less than the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is unqualified, triggering the fourth early warning instruction and generating the fourth strategy: activating global linkage optimization, linking the building's fire smoke exhaust system and positive pressure air supply system to rebalance the overall flow field; adjusting the air volume and velocity distribution of fire smoke exhaust outlets and positive pressure air supply outlets, obtaining the optimal adjustment path through intelligent algorithms to ensure balanced airflow throughout the building; and synchronously adjusting all fans in fire escape routes to maintain the positive pressure of the entire building within the optimal range, avoiding local negative pressure or backflow phenomena.

[0015] Preferably, the fire escape gas backflow prevention and regulation system includes: The data acquisition module is used to construct fire passage test conditions under simulated building fire and emergency smoke exhaust environments. Pressure sensors, temperature sensors, wind speed sensors and gas composition sensors are deployed inside and outside the fire passage to collect real-time air pressure data, temperature data inside and outside the fire passage, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. The backflow risk assessment module is used to process the collected data using differential, spatiotemporal registration, moving average, and normalized weighting methods to obtain the real-time pressure difference between the inside and outside of the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index The backflow risk index RRI is calculated and compared with the backflow risk threshold Rth to determine whether there is backflow risk in the fire escape route. If there is, corresponding strategies are given. The wall-attachment backflow assessment module is used to collect wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall-attachment effect coefficient BCI, and compare it with the wall-attachment backflow risk threshold Bth to determine whether there is a risk of wall-attachment backflow in the fire passage. If so, corresponding strategies are given. The turbulence disturbance assessment module is used to analyze wind speed distribution data within fire escape routes and obtain the instantaneous wind speed variance. and cross-sectional average wind speed The turbulence disturbance coefficient TDI is calculated and compared with the turbulence disturbance threshold Tth to determine whether the airflow in the fireproof passage is stable. If it is not stable, corresponding strategies are given. The integrated feedback module is used to perform secondary data collection after executing the backflow prevention strategies in steps two, three, and four, and to calculate the backflow risk index after the backflow prevention strategies are implemented. Boundary layer adhesion coefficient and turbulence disturbance coefficient Further calculate the comprehensive feedback effect index (CFEI) and compare it with the comprehensive backflow prevention effect threshold (Cth) to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, give appropriate strategies.

[0016] This invention provides a method and system for regulating gas flow in fire-resistant passages. It offers the following advantages: (1) The gas backflow prevention and regulation method and system for fire-resistant passages, by deploying pressure, temperature, wind speed and gas composition sensors inside and outside the fire-resistant passages, and combining differential, spatiotemporal registration, moving average and normalized weighting processing methods, can simultaneously obtain multiple key parameters such as air pressure difference, temperature gradient, wind speed and concentration of harmful gases, and construct backflow risk index RRI. Compared with traditional single wind speed or pressure monitoring methods, the present invention realizes the comprehensive judgment of multi-physical field fusion, effectively improving the accuracy and real-time performance of backflow risk assessment.

[0017] (2) The gas backflow prevention and control method and system for fire passages can identify overall backflow risk, wall-attached backflow risk and turbulent disturbance risk by setting three levels of judgment indicators: backflow risk index RRI, boundary layer wall effect coefficient BCI and turbulence disturbance coefficient TDI. It can also match layered and zoned backflow prevention and control strategies, such as adjusting fire dampers, linking ventilation fans and smoke exhaust valves, controlling regulating valves and constant air volume valves, etc., to achieve precise backflow prevention and control and ensure the stability and reliability of airflow organization in fire passages.

[0018] (3) The gas backflow prevention and control method and system for fire-resistant passages achieves a quantitative assessment of the backflow risk control effect through secondary data acquisition and calculation of the comprehensive feedback effect index (CFEI), and compares it with a preset threshold. When the backflow prevention effect is insufficient, a global linkage optimization strategy is triggered to coordinate the static pressure box, aluminum alloy air outlets and air supply and exhaust systems for overall adjustment, forming a dynamic adaptive closed-loop control mechanism, effectively avoiding the hidden dangers of secondary backflow or uneven airflow.

[0019] (4) The gas backflow prevention and regulation method and system for fire-resistant passages, which includes a data acquisition module, a backflow risk assessment module, a wall-attached backflow assessment module, a turbulence disturbance assessment module, and a comprehensive feedback module, can seamlessly connect with the building's fire smoke exhaust system and positive pressure ventilation system. Its advantages are that it can not only quickly prevent backflow under fire conditions, but also intelligently link multiple types of equipment to achieve multi-dimensional coordinated control from local to global levels, significantly improving the gas backflow prevention capability of fire-resistant passages and the overall fire safety level of the building. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the steps of the fireproof passage gas backflow prevention and regulation method of the present invention; Figure 2 This is a flowchart of the fireproof passage gas backflow prevention and regulation system of the present invention. Detailed Implementation

[0021] 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.

[0022] Example 1 Please see Figure 1 This invention provides a method for regulating gas backflow prevention in fire escape routes, comprising the following steps: Step 1: Construct a fire escape test condition under simulated building fire and emergency smoke exhaust environment. Deploy pressure sensors, temperature sensors, wind speed sensors and gas composition sensors inside and outside the fire escape to collect real-time air pressure data, temperature data inside and outside the fire escape, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. Step 2: Process the collected data using differential, spatiotemporal registration, moving average and normalized weighting methods to obtain the real-time pressure difference inside and outside the fire passage, the temperature gradient on both sides of the fire passage, the wind speed Vw in the fire passage and the comprehensive harmful gas concentration index. Calculate the backflow risk index RRI and compare it with the backflow risk threshold Rth to determine whether there is a backflow risk in the fire passage. If there is, provide corresponding strategies. Step 3: By collecting wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall adhesion effect coefficient BCI, and compare it with the wall adhesion backflow risk threshold Bth to determine whether there is a risk of wall adhesion backflow in the fire passage. If so, give appropriate strategies. Step 4: By analyzing the wind speed distribution data in the fire escape route, obtain the instantaneous wind speed variance and the cross-sectional average wind speed, calculate the turbulence disturbance coefficient TDI, and compare it with the turbulence disturbance threshold Tth to determine whether the airflow in the fire escape route is stable. If it is not stable, give appropriate strategies. Step 5: After implementing the backflow prevention strategies in Steps 2, 3, and 4, perform secondary data collection to calculate the backflow risk index, boundary layer wall effect coefficient, and turbulence disturbance coefficient after implementing the backflow prevention strategies. Further calculate the comprehensive feedback effect index CFEI and compare it with the comprehensive backflow prevention effect threshold Cth to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, apply the corresponding strategy.

[0023] In this embodiment, by simultaneously collecting multi-dimensional data such as air pressure, temperature, wind speed, and gas composition inside and outside the fire passage, and combining the classification and judgment methods of backflow risk index RRI, boundary layer adhesion coefficient BCI, and turbulence disturbance coefficient TDI, and introducing the comprehensive feedback effect index CFEI for secondary verification, a closed-loop backflow prevention control mechanism from detection-evaluation-regulation-feedback is formed. This mechanism can realize real-time monitoring and dynamic adjustment of backflow risk in fire passages. Compared with traditional single-parameter control methods, it significantly improves the scientificity, accuracy, and reliability of backflow prevention adjustment in fire passages.

[0024] Example 2 This embodiment is an explanation based on Embodiment 1. Please refer to it. Figure 1 Specifically, step one includes: S11. Under simulated building fire and emergency smoke exhaust environment, construct fire passage test conditions, and install pressure sensors at both ends and the middle of the fire passage to collect air pressure data on the inside and outside of the fire passage in real time. S12. Temperature sensors are installed at different heights and locations in the fire escape to collect temperature data inside and outside the fire escape simultaneously. S13. Collect wind speed time series data by deploying wind speed sensors at key nodes of fire escape routes; S14. Collect concentration data of carbon monoxide, carbon dioxide and smoke particles through a multi-fireproof channel gas composition sensor.

[0025] In this embodiment, by deploying pressure, temperature, wind speed, and gas composition sensors at different locations in the fire escape route, real-time acquisition of multi-dimensional environmental parameters can be achieved under simulated fire and emergency smoke extraction environments. This forms a complete monitoring data foundation covering air pressure, temperature, airflow, and smoke concentration, providing accurate and comprehensive support for subsequent backflow risk assessment and backflow prevention adjustment. Compared with single parameter acquisition methods, this significantly improves the completeness and reliability of monitoring.

[0026] Example 3 This embodiment is an explanation based on Embodiment 2. Please refer to it. Figure 1 Specifically, step two includes: S21. By comparing the air pressure data inside and outside the fire escape route using differential calculation methods, the real-time pressure difference between the two sets of air pressure values ​​is obtained. By collecting temperature data and employing spatiotemporal registration and differential calculation methods, the temperature gradient on both sides of the fire escape route was obtained. The wind speed Vw in fire escape routes was obtained by collecting time-series wind speed data and removing instantaneous fluctuations using a moving average algorithm. A comprehensive hazardous gas concentration index was obtained by collecting concentration data of carbon monoxide, carbon dioxide, and particulate matter using a normalized weighted fusion method. .

[0027] In this embodiment, by processing multi-source data such as air pressure, temperature, wind speed, and concentration of harmful gases using methods such as differential, spatiotemporal registration, moving average, and normalized weighting, it is possible not only to effectively reduce the interference caused by fluctuations in a single parameter, but also to integrate them into a comprehensive evaluation index, thereby improving the accuracy and stability of the backflow risk assessment and ensuring the scientific nature of the regulation strategy.

[0028] Example 4 This embodiment is an explanation based on Embodiment 3. Please refer to it. Figure 1 Specifically, step two also includes: S22, By obtaining the real-time pressure difference inside and outside the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and overall harmful gas concentration index After dimensionless processing, the reverse flow risk index (RRI) is calculated using the following formula:

[0029] In the formula, a1, a2, a3, and a4 represent weighting coefficients; The methods for obtaining a1, a2, a3, and a4 are as follows: Statistical analysis was conducted on a large amount of fire simulation experiments and airflow monitoring data from building fire escape routes. Regression fitting and sensitivity analysis were performed on the influence weights of four indicators—pressure difference, temperature gradient, wind speed, and harmful gas concentration—using multi-scenario test samples. A reasonable weight allocation ratio was determined by combining the experience and judgment of fire safety experts and fluid mechanics researchers. Relevant standards such as the "Code for Fire Protection Design of Buildings" and the "Technical Standard for Smoke Control Systems in Buildings" were referenced, as these standards typically guide the relative importance of air pressure difference, temperature difference, and smoke composition in backflow risk assessment. This weighting setting is used to scientifically balance the influence of multiple physical field factors, improve the comprehensive evaluation accuracy and application effect of the Backflow Risk Index (RRI), and ensure the rationality and effectiveness of the judgment. Characterizing air pressure difference The impact on the backflow risk index (RRI) is significant and is a key factor that directly reflects the dominant role of the air pressure difference inside and outside the fire escape route on the stability of the airflow direction. Characterizing temperature gradient The impact on the backflow risk index RRI has a medium weight, reflecting the contribution of buoyancy drive caused by the chimney effect to the flue gas backflow trend. : Characterizes the impact of wind speed Vw on the reverse flow risk index RRI, accounting for a minor weight, reflecting the disruptive effect of the interaction between external wind disturbance and airflow within the channel; Characterizing the overall concentration of harmful gases The impact on the backflow risk index (RRI) has a secondary weight, reflecting the additional pressure that the accumulation of smoke and harmful gases puts on channel safety. By constructing a backflow risk index (RRI) that is a weighted fusion of a1, a2, a3 and a4, the combined effect of multiple physical field factors can be quantified, providing a scientific basis for the safety assessment of airflow in fire escape routes and backflow early warning strategies. S23. By setting a backflow risk threshold Rth and comparing the backflow risk index RRI with the backflow risk threshold Rth, the first assessment results are obtained, including: When the backflow risk index RRI < backflow risk threshold Rth, it indicates that there is no backflow risk in the fire escape route, and continuous monitoring is required. When the backflow risk index RRI is greater than or equal to the backflow risk threshold Rth, it indicates that there is a backflow risk in the fire passage, triggering the first warning instruction and generating the first strategy: adjust the opening of the fire damper to reduce the cross-sectional area of ​​the fire passage and increase airflow resistance; start the ventilation fan to establish positive pressure airflow inside the fire passage to counteract the backflow trend; and, based on the gas composition monitoring results, link the smoke exhaust valve to quickly discharge high-concentration harmful smoke.

[0030] The backflow risk threshold Rth is obtained by: statistically analyzing actual fire accident data and laboratory fire passage simulation test data to extract the distribution range of the backflow risk index RRI between "no backflow state" and "significant backflow state"; combining the experience judgment of fire safety engineers and building ventilation experts to determine a reasonable judgment value; referring to relevant building smoke control safety codes, which usually give parameter ranges for backflow judgment and smoke control; this threshold is used to effectively distinguish whether there is a backflow risk in the fire passage, and assist in accurately triggering early warning and protection strategies.

[0031] In this embodiment, by constructing a backflow risk index RRI and combining it with a backflow risk threshold Rth for dynamic comparative analysis, multiple physical field indicators such as air pressure difference, temperature gradient, wind speed, and concentration of harmful gases inside and outside the fire passage can be weighted and integrated to form a unified risk judgment basis. When backflow risk is detected, an integrated control strategy can be automatically triggered, including fire damper adjustment, positive pressure establishment of ventilation fans, and smoke exhaust valve linkage exhaust, to achieve early warning and rapid intervention for backflow risk in fire passages, effectively improving the real-time performance and reliability of smoke spread prevention and control.

[0032] Example 5 This embodiment is an explanation based on Embodiment 4. Please refer to it. Figure 1 Step three includes: S31. By collecting time series data of wind speed at different locations on the cross-section of the fire passage, using a multi-point wind speed sensor array and time series acquisition technology, the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall are extracted, and the data are normalized.

[0033] In this embodiment, by simultaneously extracting the average wind speed on the wall surface and the central axial wind speed on the cross-section of the fire escape passage and performing normalization processing, the airflow distribution characteristics can be comprehensively reflected, avoiding the one-sidedness caused by relying solely on single-point wind speed measurement, thereby improving the accuracy of backflow risk assessment and the reliability of passage airflow control strategy.

[0034] Example 6 This embodiment is an explanation based on Embodiment 5. Please refer to it. Figure 1 Specifically, step three also includes: S32. Calculate the boundary layer adhesion coefficient (BCI) by using the average wind speed Vwall and the central axial wind speed Vcenter of the treated fire passage wall, as shown in the following formula: ;

[0035] In the formula, This represents a very small constant to prevent the denominator from being zero; Molecular part : Represents the average wind speed on the wall of the fire escape route. It is used to reflect the constraint and stabilizing effect of the boundary layer on the overall airflow distribution and is a key indicator for judging the strength of the wall attachment effect. denominator : Indicates the axial wind speed at the center of the fire escape route, reflecting the core flow intensity of the main airflow channel and being the primary driving force behind the counter-current trend; Additional Item This represents a very small constant to prevent the denominator from being zero, used to avoid denominator distortion when the wall wind speed is close to or equal to zero; When the BCI value is large, it indicates that the proportion of airflow on the wall is enhanced, which forms a strong constraint on the central airflow, the airflow distribution in the channel is balanced, and the risk of backflow is low. When the BCI value is small, it indicates that the central airflow is significantly stronger than the wall airflow, the boundary layer constraint is weakened, and the risk of wall backflow increases. The strategy is to adjust the airflow distribution or enhance the stability of the wall airflow. S33. By setting a pre-defined wall adhesion backflow risk threshold Bth, and comparing the boundary layer wall adhesion effect coefficient BCI with the wall adhesion backflow risk threshold Bth, the second assessment results are obtained, including: When the boundary layer adhesion effect coefficient BCI < the adhesion backflow risk threshold Bth, it indicates that there is no risk of adhesion backflow in the fire passage, the airflow distribution in the fire passage is balanced, and continuous monitoring is required. When the boundary layer adhesion effect coefficient BCI is greater than or equal to the adhesion backflow risk threshold Bth, it indicates that there is an adhesion backflow risk in the fire passage, triggering the second early warning command and generating the second strategy: adjust the air volume distribution of the regulating valve to increase the central airflow energy; link the constant air volume valve to maintain constant air supply in different branches to weaken near-wall backflow; and change the air outlet angle through the aluminum alloy air outlet to guide the airflow to the central area and suppress wall rollback.

[0036] The threshold Bth for wall-attached backflow risk is obtained by statistically analyzing the ratio of the central axial wind speed to the average wall wind speed in fire passages under different airflow distributions, cross-sectional velocity distributions, and wall-attachment effects. Combined with wind tunnel experiments and fire scenario simulations, a reasonable boundary layer attachment effect judgment value is determined. Referring to the design code for building smoke control and exhaust systems and the standard for numerical simulation of fluid mechanics, this threshold is used to distinguish whether there is a significant risk of near-wall backflow and backflow in fire passages, ensuring balanced airflow distribution and backflow suppression capabilities.

[0037] In this embodiment, by setting a comparative analysis of the boundary layer adhesion coefficient (BCI) and the threshold (Bth), it is possible to accurately identify whether there is a risk of backflow near the wall in the fire passage. When the risk is triggered, a comprehensive adjustment strategy including air volume distribution, constant air volume control and air outlet guidance is automatically generated, thereby effectively weakening near-wall backflow, enhancing the stability of central airflow, ensuring balanced airflow distribution in the fire passage, and significantly improving the reliability and safety of backflow prevention and control.

[0038] Example 7 This embodiment is an explanation based on Embodiment 6. Please refer to it. Figure 1 Specifically, step four includes: S41. By analyzing the wind speed distribution data within the fire escape route, the instantaneous wind speed sequence at each measuring point on the key cross-section of the fire escape route is extracted; the instantaneous wind speed variance is obtained using the sliding time window statistical and variance calculation method. The average wind speed of the cross section is obtained by combining the mean filtering algorithm. .

[0039] In this embodiment, by performing sliding time window statistics and variance calculation on the instantaneous wind speed at each measuring point on the key cross section of the fire escape, and combining the mean filtering algorithm to extract the cross section average wind speed, it can not only accurately reflect the fluctuation characteristics of airflow in time and space, but also effectively distinguish between the stable flow and turbulent disturbance state of airflow, thus providing highly reliable basic data support for the subsequent calculation of turbulence disturbance coefficient and dynamic assessment of backflow risk.

[0040] Example 8 This embodiment is an explanation based on Embodiment 7. Please refer to it. Figure 1 Specifically, step four also includes: S42. By obtaining the instantaneous wind speed variance and cross-sectional average wind speed After dimensionless processing, the turbulence disturbance coefficient TDI is calculated using the following formula: ;

[0041] In the formula, This represents a very small constant to prevent the denominator from being zero; Molecular part : Represents the instantaneous variance of wind speed at key cross-sections of the channel. It is used to reflect the intensity of local airflow velocity fluctuations and is an important indicator for measuring the level of turbulence disturbance. The larger the value, the more unstable the flow field. denominator This indicates the average wind speed at this cross-section, reflecting the baseline flow level of the overall airflow within the channel and serving as a reference for comparing the amplitude of instantaneous disturbances; Additional Items This represents a very small constant to prevent the denominator from being zero, and is used to prevent denominator distortion when the average wind speed is close to or equal to zero. When the TDI value is large, it indicates that the wind speed fluctuation range accounts for a relatively high proportion of the average wind speed, the turbulence is strong, the airflow distribution in the channel is uneven, and the risk of backflow and recirculation is significantly increased. A lower TDI value indicates weaker wind speed fluctuations, stable airflow characteristics, and a lower risk of backflow. The corresponding strategy is to use flow deflectors or adjust the air supply frequency when TDI is high to reduce turbulence and improve airflow stability in the channel. S43. By setting a preset turbulence disturbance threshold Tth, and comparing and analyzing the turbulence disturbance coefficient TDI with the turbulence disturbance threshold Tth, the third evaluation results are obtained, including: When the turbulence disturbance coefficient TDI < turbulence disturbance threshold Tth, it indicates that the airflow in the fireproof passage is stable, there is no risk of backflow, and continuous monitoring is required. When the turbulence disturbance coefficient TDI ≥ turbulence disturbance threshold Tth, it indicates that the airflow in the fire passage is unstable, and there is a risk of local eddies, backflow fire passage formation, and reverse gas entrainment. This triggers the third warning instruction and generates the third strategy: start the ventilation fan to increase the airflow frequency and form a uniform positive pressure zone to weaken the instantaneous impact; use a combination of fire dampers and regulating valves to locally change the airflow organization in the fire passage and break the vortex; use aluminum alloy air outlets to adjust the airflow jet direction and establish airflow barriers at key sections; combine constant air volume valves and static pressure boxes to form a stable air supply pattern and reduce eddies and backflow; and link the smoke exhaust valve to quickly extract the high-temperature smoke entrained by turbulence.

[0042] The turbulence disturbance threshold Tth is obtained by conducting large-sample monitoring and statistical analysis of the ratio of instantaneous wind speed variance to cross-sectional average wind speed in fire passages, combined with eddy formation conditions and airflow stability assessment experiments under typical working conditions, to determine a reasonable turbulence disturbance judgment value. Referring to the airflow stability test specifications for building ventilation and smoke exhaust systems, this threshold is used to distinguish between the stability and turbulence risk of airflow in fire passages, ensuring the continuity of airflow organization and the controllability of backflow risk.

[0043] In this embodiment, by calculating the turbulence disturbance coefficient TDI and comparing it with the turbulence disturbance threshold Tth, the stability and turbulence of the airflow in the fire passage can be quantitatively reflected, enabling early warning of the risks of local eddies, backflow, and reverse entrainment. Combined with the coordinated control of ventilation fans, fire dampers, regulating valves, and smoke exhaust valves, the airflow organization can be quickly adjusted in the early stage of turbulence, a positive pressure barrier can be established, and high-temperature smoke can be removed in time, thereby effectively avoiding the aggravation of backflow and significantly improving the stability and safety of the fire passage under fire and smoke exhaust conditions.

[0044] Example 9 This embodiment is an explanation based on Embodiment 8. Please refer to it. Figure 1 Specifically, step five includes: S51. After executing the backflow prevention strategy in steps two, three, and four, perform secondary data acquisition to re-acquire the real-time pressure difference inside and outside the fire escape after the backflow prevention strategy is implemented. Temperature gradient on both sides of the fire escape Fire escape route wind speed Comprehensive harmful gas concentration index Average wind speed on fire escape route walls Central axis wind speed Instantaneous wind speed variance and cross-sectional average wind speed Calculate the backflow risk index after the backflow prevention strategy. Boundary layer adhesion coefficient and turbulence disturbance coefficient The values ​​of the reverse flow risk index (RRI), boundary layer adhesion coefficient (BCI), and turbulence disturbance coefficient (TDI) before the reverse flow prevention strategy were compared. After dimensionless processing, the comprehensive feedback effect index (CFEI) was calculated, as shown in the following formula: ;

[0045] In the formula, w1, w2, and w3 represent weighting coefficients; The acquisition methods for w1, w2, and w3 are as follows: Statistical analysis was conducted on a large amount of airflow monitoring data before and after the implementation of backflow prevention strategies in fire escape routes. Regression fitting and sensitivity analysis were performed on the improvement magnitude of three indicators—the backflow risk index (RRI), the boundary layer adhesion coefficient (BCI), and the turbulence disturbance coefficient (TDI)—using multi-scenario experimental samples. A reasonable weighting ratio was determined by combining the experience and judgment of fire safety experts, fluid mechanics researchers, and building smoke exhaust system engineers. Relevant standards such as the "Code for Fire Protection Design of Buildings" and the "Technical Standard for Building Smoke Control Systems" were referenced to guide the relative importance of each indicator in the comprehensive backflow prevention effect evaluation. This weighting setting is used to scientifically balance the feedback effects of multiple physical field factors under the backflow prevention strategy, improve the evaluation accuracy and application reliability of the comprehensive feedback effect index (CFEI), and ensure the rationality and effectiveness of the judgment. The countercurrent risk index (RRI) is a core factor that represents the contribution of the countercurrent prevention strategy to the improvement of the RRI. It has a high weight and directly reflects the strategy's ability to suppress the countercurrent trend of the main airflow. The contribution of the anti-reverse strategy to the improvement of the boundary layer adhesion coefficient (BCI) is represented by a medium weight, reflecting the role of the strategy in the balance between wall airflow constraint and core flow. The contribution of the anti-reverse strategy to the improvement of the turbulence disturbance coefficient (TDI) is characterized by its minor weight, reflecting the interference suppression effect of the strategy in reducing local eddies and the risk of backflow. By constructing a comprehensive feedback effect index (CFEI) that is a weighted fusion of w1, w2, and w3, the comprehensive effect of the backflow prevention strategy on multiple physical field factors can be quantified, providing a scientific basis for optimizing the airflow safety and adjusting the strategy in fire-resistant passages. S52. By setting a comprehensive backflow prevention effect threshold Cth, and comparing and analyzing the comprehensive feedback effect index CFEI with the comprehensive backflow prevention effect threshold Cth, the fourth evaluation results are obtained, including: When the comprehensive feedback effect index CFEI is greater than or equal to the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is qualified and should be continuously monitored. When the comprehensive feedback effect index CFEI is less than the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is unqualified, triggering the fourth early warning instruction and generating the fourth strategy: activating global linkage optimization, linking the building's fire smoke exhaust system and positive pressure air supply system to rebalance the overall flow field; adjusting the air volume and velocity distribution of fire smoke exhaust outlets and positive pressure air supply outlets, obtaining the optimal adjustment path through intelligent algorithms to ensure balanced airflow throughout the building; and synchronously adjusting all fans in fire escape routes to maintain the positive pressure of the entire building within the optimal range, avoiding local negative pressure or backflow phenomena.

[0046] The comprehensive backflow prevention effect threshold Cth is obtained by statistical modeling and multi-scenario experimental analysis of the differences in backflow risk index, boundary layer wall effect coefficient, and turbulence disturbance coefficient before and after the implementation of the backflow prevention strategy. The dimensionless normalization method is used to evaluate the degree of improvement of the overall flow field by the backflow prevention measures and determine a reasonable comprehensive judgment value. Referring to the fire safety performance-based design guidelines and the comprehensive performance test specifications for building smoke control systems, this threshold is used to distinguish the effectiveness of backflow prevention measures in global airflow balance and safety protection, ensuring the scientific nature and sustainability of strategy implementation.

[0047] In this embodiment, by introducing the Comprehensive Feedback Effect Index (CFEI), the changes in the Backflow Risk Index (RRI), Boundary Layer Attachment Effect Coefficient (BCI), and Turbulence Disturbance Coefficient (TDI) are weighted and fused to achieve a quantitative evaluation of the effects before and after the backflow prevention strategy. By comparing with the comprehensive backflow prevention effect threshold (Cth), not only can the effectiveness of the local strategy be verified, but also global linkage optimization can be triggered when the backflow prevention effect is insufficient. This coordinates the overall operation of the fire smoke exhaust system, positive pressure air supply system, and fans in fire passages, forming an airflow rebalancing throughout the building, avoiding the recurrence of local negative pressure or backflow, and significantly improving the continuous stability and overall protection level of the backflow prevention measures in fire passages.

[0048] Example 10 Please refer to Figure 2 Fire escape gas backflow prevention and control system, including: The data acquisition module is used to construct fire passage test conditions under simulated building fire and emergency smoke exhaust environments. Pressure sensors, temperature sensors, wind speed sensors and gas composition sensors are deployed inside and outside the fire passage to collect real-time air pressure data, temperature data inside and outside the fire passage, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. The backflow risk assessment module is used to process the collected data using differential, spatiotemporal registration, moving average, and normalized weighting methods to obtain the real-time pressure difference between the inside and outside of the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index The backflow risk index RRI is calculated and compared with the backflow risk threshold Rth to determine whether there is backflow risk in the fire escape route. If there is, corresponding strategies are given. The wall-attachment backflow assessment module is used to collect wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall-attachment effect coefficient BCI, and compare it with the wall-attachment backflow risk threshold Bth to determine whether there is a risk of wall-attachment backflow in the fire passage. If so, corresponding strategies are given. The turbulence disturbance assessment module is used to analyze wind speed distribution data within fire escape routes and obtain the instantaneous wind speed variance. and cross-sectional average wind speed The turbulence disturbance coefficient TDI is calculated and compared with the turbulence disturbance threshold Tth to determine whether the airflow in the fireproof passage is stable. If it is not stable, corresponding strategies are given. The integrated feedback module is used to perform secondary data collection after executing the backflow prevention strategies in steps two, three, and four, and to calculate the backflow risk index after the backflow prevention strategies are implemented. Boundary layer adhesion coefficient and turbulence disturbance coefficient Further calculate the comprehensive feedback effect index (CFEI) and compare it with the comprehensive backflow prevention effect threshold (Cth) to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, give appropriate strategies.

[0049] In this embodiment, a multi-source data-driven, end-to-end backflow prevention control system is formed by setting up five modules: data acquisition, backflow risk assessment, wall-attached backflow assessment, turbulence disturbance assessment, and comprehensive feedback. This system can not only perform multi-dimensional analysis of air pressure difference, temperature gradient, wind speed distribution, and harmful gas concentration in fire escape routes, but also combine boundary layer effects and turbulence disturbance characteristics to achieve graded early warning and strategy generation. The comprehensive feedback module further verifies the effectiveness of local strategies and optimizes the overall system, ensuring the continuity of backflow prevention measures and the overall balance of airflow organization throughout the building, thereby significantly improving the safety and stability of fire escape routes under fire and emergency smoke extraction conditions.

[0050] The threshold is set to facilitate comparison. The size of the threshold depends on the amount of sample data and the number of bases set by those skilled in the art for each set of sample data; as long as it does not affect the ratio between the parameter and the quantized value, it is acceptable.

[0051] The above formulas are all derived from software simulation using a large amount of data, and are selected to be close to the actual values. The coefficients in the formulas are set by those skilled in the art based on the actual situation. The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for regulating gas flow in fire-resistant passages, characterized in that, Includes the following steps: Step 1: Construct a fire escape test condition under simulated building fire and emergency smoke exhaust environment. Deploy pressure sensors, temperature sensors, wind speed sensors and gas composition sensors inside and outside the fire escape to collect real-time air pressure data, temperature data inside and outside the fire escape, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. Step 2: Process the collected data using differential, spatiotemporal registration, moving average, and normalized weighting methods to obtain the real-time pressure difference between the inside and outside of the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index The backflow risk index RRI is calculated and compared with the backflow risk threshold Rth to determine whether there is backflow risk in the fire escape route. If there is, corresponding strategies are given. Step 3: By collecting wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall adhesion effect coefficient BCI, and compare it with the wall adhesion backflow risk threshold Bth to determine whether there is a risk of wall adhesion backflow in the fire passage. If so, give appropriate strategies. Step 4: Obtain the instantaneous wind speed variance by analyzing the wind speed distribution data within the fire escape route. and cross-sectional average wind speed The turbulence disturbance coefficient TDI is calculated and compared with the turbulence disturbance threshold Tth to determine whether the airflow in the fireproof passage is stable. If it is not stable, corresponding strategies are given. Step 5: After implementing the backflow prevention strategies in Steps 2, 3, and 4, perform a second data collection to calculate the backflow risk index after implementing the backflow prevention strategies. Boundary layer adhesion coefficient and turbulence disturbance coefficient Further calculate the comprehensive feedback effect index (CFEI) and compare it with the comprehensive backflow prevention effect threshold (Cth) to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, give appropriate strategies.

2. The method for regulating gas flow in fireproof passages according to claim 1, characterized in that, Step one includes: S11. Under simulated building fire and emergency smoke exhaust environment, construct fire passage test conditions, and install pressure sensors at both ends and the middle of the fire passage to collect air pressure data on the inside and outside of the fire passage in real time. S12. Temperature sensors are installed at different heights and locations in the fire escape to collect temperature data inside and outside the fire escape simultaneously. S13. Collect wind speed time series data by deploying wind speed sensors at key nodes of fire escape routes; S14. Collect concentration data of carbon monoxide, carbon dioxide and smoke particles through a multi-fireproof channel gas composition sensor.

3. The method for regulating gas backflow prevention in fireproof passages according to claim 2, characterized in that, Step two includes: S21. By comparing the air pressure data inside and outside the fire escape route using differential calculation methods, the real-time pressure difference between the two sets of air pressure values ​​is obtained. By collecting temperature data and employing spatiotemporal registration and differential calculation methods, the temperature gradient on both sides of the fire escape route was obtained. The wind speed Vw in fire escape routes was obtained by collecting time-series wind speed data and removing instantaneous fluctuations using a moving average algorithm. A comprehensive hazardous gas concentration index was obtained by collecting concentration data of carbon monoxide, carbon dioxide, and particulate matter using a normalized weighted fusion method. .

4. The method for regulating gas flow in fireproof passages according to claim 3, characterized in that, Step two also includes: S22, By obtaining the real-time pressure difference inside and outside the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index After dimensionless processing, the reverse flow risk index RRI is calculated and obtained. S23. By setting a backflow risk threshold Rth and comparing the backflow risk index RRI with the backflow risk threshold Rth, the first assessment results are obtained, including: When the backflow risk index RRI < backflow risk threshold Rth, it indicates that there is no backflow risk in the fire escape route, and continuous monitoring is required. When the backflow risk index RRI is greater than or equal to the backflow risk threshold Rth, it indicates that there is a backflow risk in the fire passage, triggering the first warning instruction and generating the first strategy: adjust the opening of the fire damper to reduce the cross-sectional area of ​​the fire passage and increase airflow resistance; start the ventilation fan to establish positive pressure airflow inside the fire passage to counteract the backflow trend; and, based on the gas composition monitoring results, link the smoke exhaust valve to quickly discharge high-concentration harmful smoke.

5. The method for regulating gas backflow prevention in fireproof passages according to claim 4, characterized in that, Step three includes: S31. By collecting time series data of wind speed at different locations on the cross-section of the fire passage, using a multi-point wind speed sensor array and time series acquisition technology, the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall are extracted, and the data are normalized.

6. The method for regulating gas backflow prevention in fireproof passages according to claim 5, characterized in that, Step three also includes: S32. Calculate the boundary layer adhesion coefficient BCI by using the average wind speed Vwall on the treated fire passage wall and the central axial wind speed Vcenter. S33. By setting a pre-defined wall adhesion backflow risk threshold Bth, and comparing the boundary layer wall adhesion effect coefficient BCI with the wall adhesion backflow risk threshold Bth, the second assessment results are obtained, including: When the boundary layer adhesion effect coefficient BCI < the adhesion backflow risk threshold Bth, it indicates that there is no risk of adhesion backflow in the fire passage, the airflow distribution in the fire passage is balanced, and continuous monitoring is required. When the boundary layer adhesion effect coefficient BCI is greater than or equal to the adhesion backflow risk threshold Bth, it indicates that there is an adhesion backflow risk in the fire passage, triggering the second early warning command and generating the second strategy: adjust the air volume distribution of the regulating valve to increase the central airflow energy; link the constant air volume valve to maintain constant air supply in different branches to weaken near-wall backflow; and change the air outlet angle through the aluminum alloy air outlet to guide the airflow to the central area and suppress wall rollback.

7. The method for regulating gas backflow prevention in fireproof passages according to claim 6, characterized in that, Step four includes: S41. By analyzing the wind speed distribution data within the fire escape route, the instantaneous wind speed sequence at each measuring point on the key cross-section of the fire escape route is extracted; the instantaneous wind speed variance is obtained using the sliding time window statistical and variance calculation method. The average wind speed of the cross section is obtained by combining the mean filtering algorithm. .

8. The method for regulating gas flow in fireproof passages according to claim 7, characterized in that, Step four also includes: S42. By obtaining the instantaneous wind speed variance and cross-sectional average wind speed After dimensionless processing, the turbulence disturbance coefficient TDI is calculated and obtained; S43. By setting a preset turbulence disturbance threshold Tth, and comparing and analyzing the turbulence disturbance coefficient TDI with the turbulence disturbance threshold Tth, the third evaluation results are obtained, including: When the turbulence disturbance coefficient TDI < turbulence disturbance threshold Tth, it indicates that the airflow in the fireproof passage is stable, there is no risk of backflow, and continuous monitoring is required. When the turbulence disturbance coefficient TDI ≥ turbulence disturbance threshold Tth, it indicates that the airflow in the fire passage is unstable, and there is a risk of local eddies, backflow fire passage formation, and reverse gas entrainment. This triggers the third warning instruction and generates the third strategy: start the ventilation fan to increase the airflow frequency and form a uniform positive pressure zone to weaken the instantaneous impact; use a combination of fire dampers and regulating valves to locally change the airflow organization in the fire passage and break the vortex; use aluminum alloy air outlets to adjust the airflow jet direction and establish airflow barriers at key sections; combine constant air volume valves and static pressure boxes to form a stable air supply pattern and reduce eddies and backflow; and link the smoke exhaust valve to quickly extract the high-temperature smoke entrained by turbulence.

9. The method for regulating gas backflow prevention in fireproof passages according to claim 8, characterized in that, Step five includes: S51. After executing the backflow prevention strategy in steps two, three, and four, perform secondary data acquisition to re-acquire the real-time pressure difference inside and outside the fire escape after the backflow prevention strategy is implemented. Temperature gradient on both sides of the fire escape Fire escape route wind speed Comprehensive harmful gas concentration index Average wind speed on fire escape route walls Central axis wind speed Instantaneous wind speed variance and cross-sectional average wind speed Calculate the backflow risk index after the backflow prevention strategy. Boundary layer adhesion coefficient and turbulence disturbance coefficient The values ​​of the reverse flow risk index RRI, boundary layer adhesion effect coefficient BCI, and turbulence disturbance coefficient TDI before the reverse flow prevention strategy were compared. After dimensionless processing, the comprehensive feedback effect index CFEI was calculated. S52. By setting a comprehensive backflow prevention effect threshold Cth, and comparing and analyzing the comprehensive feedback effect index CFEI with the comprehensive backflow prevention effect threshold Cth, the fourth evaluation results are obtained, including: When the comprehensive feedback effect index CFEI is greater than or equal to the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is qualified and should be continuously monitored. When the comprehensive feedback effect index CFEI is less than the comprehensive backflow prevention effect threshold Cth, it indicates that the comprehensive backflow prevention effect is unqualified, triggering the fourth early warning instruction and generating the fourth strategy: activating global linkage optimization, linking the building's fire smoke exhaust system and positive pressure air supply system to rebalance the overall flow field; adjusting the air volume and velocity distribution of fire smoke exhaust outlets and positive pressure air supply outlets, obtaining the optimal adjustment path through intelligent algorithms to ensure balanced airflow throughout the building; and synchronously adjusting all fans in fire escape routes to maintain the positive pressure of the entire building within the optimal range, avoiding local negative pressure or backflow phenomena.

10. A fire escape gas backflow prevention and regulation system, applied to the fire escape gas backflow prevention and regulation method according to any one of claims 1 to 9, characterized in that, include: The data acquisition module is used to construct fire passage test conditions under simulated building fire and emergency smoke exhaust environments. Pressure sensors, temperature sensors, wind speed sensors and gas composition sensors are deployed inside and outside the fire passage to collect real-time air pressure data, temperature data inside and outside the fire passage, wind speed time series data and concentration data of carbon monoxide, carbon dioxide and smoke particles. The backflow risk assessment module is used to process the collected data using differential, spatiotemporal registration, moving average, and normalized weighting methods to obtain the real-time pressure difference between the inside and outside of the fire escape route. Temperature gradient on both sides of the fire escape Fire escape route wind speed (Vw) and comprehensive hazardous gas concentration index The backflow risk index RRI is calculated and compared with the backflow risk threshold Rth to determine whether there is backflow risk in the fire escape route. If there is, corresponding strategies are given. The wall-attachment backflow assessment module is used to collect wind speed time series data at different locations on the cross-section of the fire passage, obtain the average wind speed Vwall and the central axial wind speed Vcenter of the fire passage wall, calculate the boundary layer wall-attachment effect coefficient BCI, and compare it with the wall-attachment backflow risk threshold Bth to determine whether there is a risk of wall-attachment backflow in the fire passage. If so, corresponding strategies are given. The turbulence disturbance assessment module is used to analyze wind speed distribution data within fire escape routes and obtain the instantaneous wind speed variance. and cross-sectional average wind speed The turbulence disturbance coefficient TDI is calculated and compared with the turbulence disturbance threshold Tth to determine whether the airflow in the fireproof passage is stable. If it is not stable, corresponding strategies are given. The integrated feedback module is used to perform secondary data collection after executing the backflow prevention strategies in steps two, three, and four, and to calculate the backflow risk index after the backflow prevention strategies are implemented. Boundary layer adhesion coefficient and turbulence disturbance coefficient Further calculate the comprehensive feedback effect index (CFEI) and compare it with the comprehensive backflow prevention effect threshold (Cth) to determine whether the comprehensive backflow prevention effect is qualified. If it is not qualified, give appropriate strategies.

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