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主管:中华人民共和国应急管理部
主办:应急管理部天津消防研究所
ISSN 1009-0029  CN 12-1311/TU

Table of Content

    15 August 2023, Volume 42 Issue 8 Previous Issue    Next Issue

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    Study on the influence of wind speed on the emergency discharge of hydrogen from hydrogen fuel cell vehicles
    Liu Hongyong, Fan Weiyu, Song Fei, Yan Han,
    2023, 42 (8):  1027-1031. 
    Abstract ( 520 )  
    Abstract: In the event of an emergency, a hydrogen fuel cell vehicle will actively discharge hydrogen. At present, research is needed on the safety of emergency hydrogen discharge from hydrogen fuel cell vehicles. To study the characteristics of emergency discharge of hydrogen fuel cell vehicles in open space and the influence of wind speed on them, Fluent software was used to establish a model of hydrogen fuel cell vehicles in open space, and the law of hydrogen diffusion and the development of hydrogen combustible areas and warning areas were analyzed. When hydrogen fuel cell vehicles is urgently deflated in the open space, the larger the wind speed facing the wind, the smaller the maximum volume and stable volume of the hydrogen explosion able cloud, and the less time it takes to reach the maximum volume and stable volume. The size of the hydrogen level warning area and the positive warning area decreases with the increase of the wind speed, and the shape is changed by the influence of the wind speed; after the release is stopped, the combustible gas will quickly spread and disappear. This conclusion can provide a basis for the safety verification of emergency hydrogen discharge by hydrogen fuel cell vehicles.
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    Study on the effect of separation distance on the fire spread characteristics of inclined parallel twin wires
    Zhang Peiyao, Luo Yueyang, Yang Zhengyuan, Gao Yunji
    2023, 42 (8):  1032-1037. 
    Abstract ( 646 )  
    Abstract: In this paper, a series of experiments were performed over twin parallel polyethylene copper wires with inclination angles from 0 to 90° and spacing from 0 to 17 mm, to analyze the flame pattern, flame height, length and fire spread rate during the combustion process. The results show that: (1) The flame form of inclined parallel twin wires at different distances goes through three stages such as the integrated stage, the approached stage and the independent stage; (2) both flame height (except 90° inclination), flame length, and fire spread rate of twin wires all increase with increasing inclination, while increase and then decrease with increasing spacing; (3) the fire spread rate of the twin wires was initially smaller than that of the single, gradually increased with the wire spacing and reached a maximum in the late stage of integration, and then decreased and remained identical to that of the single in the independent stage; (4) the proportional relationship between the fire spread rate and the flame length is established, and the proportional coefficient is 0.078 for fire spread over twin parallel wires, which is slightly smaller than that for the single wire.
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    Influence of ignition position and obstacles on propane air explosion in venting space
    Xu Ruizhi, Tang Baijian, Chen Li
    2023, 42 (8):  1038-1045. 
    Abstract ( 275 )  
    Abstract: In order to study the influence of ignition position and obstacles on propane air explosion in venting space, a numerical model of propane venting space was established based on CFD software FLACS. The model was verified by propane venting test results, and the calculation results of the numerical model were basically reliable. The verified numerical model is used to further study the effects of igniting position and obstacles on overpressure transients during vented explosions of propane–air mixtures. The results show that: as the distance between ignition position and explosion vent increases, the peak values of Δp1, Δp2 and pmax increase accordingly. The existence of obstacles leads to the intensification of turbulence generated by explosion. Turbulent combustion increases the combustion speed and combustion area, resulting in peak value and pressure rise speed of Δp1 increase. And a new overpressure peak pobstacle is generated in this process. In addition, it was found that the time interval between Δp1 and pobstacle peaks decreases with the increase of the venting pressure, and the two overpressure peaks are easy to merge into a larger overpressure peak.
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    Single⁃phase contact tree ground fault ignition characteristics and model analysis
    Ning Xin, He Xin, Wang Jun, Sun zhang
    2023, 42 (8):  1046-1050. 
    Abstract ( 243 )  
    Abstract: For single?phase tree ignition of vegetation and thus forest fires, in order to clarify the ignition characteristics and temperature rise mechanism of vegetation, this paper laps the test platform to conduct a study of the wire contacting pine trees and analyze the ignition phenomenon and temperature change during the ignition of vegetation by the wire contacting the tree. The analysis found that the vegetation ignition is divided into four stages: initial contact, water evaporation, carbonization channel, and spreading through; meanwhile the leakage current is also affected by the temperature showing obvious characteristics of the four stages of development; the heat of the vegetation temperature rise comes from the thermal effect of the current and heat transfer from the object. Further, according to the heat action path and temperature rise mechanism, the temperature rise model of calculating ignition point?time is proposed to predict and analyze the open flame time of vegetation spreading to different locations. The validation results show that the calculated model has high accuracy and is important for guiding the prevention and control of forest fires started by wire.
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    Effect of porous media and CO2 on inhibiting methane explosion with low hydrogen ratio
    Zheng Lulu, Duan Yulong, Li Zehuan, Jia Hailin
    2023, 42 (8):  1051-1056. 
    Abstract ( 281 )  
    Abstract: To study the explosion suppression technology of the hydrogen?doped natural gas in the pipeline, in a customized 100 mm×100 mm×1 000 mm plexiglass pipe, the synergistic effect of using porous media and CO2 to suppress the methane explosion with a hydrogen content ratio of 10% was studied, and the effect of synergistic CO2 on the different stages of flame development and the change of jet position on the explosion was explored. The results indicate that when the porous medium cooperates with CO2 at different stages of flame development, the left side wall attached CO2 jet cannot successfully quench the flame at the porous medium. When CO2 acts on the fingertip flame and the flame front is directly below the nozzle,it has a significant inhibitory effect on the flame propagation. However, the CO2 right side wall attached jet can successfully block flame propagation and has a good inhibitory effect on peak flame velocity, average flame velocity, and explosion overpressure peak. This indicates that the gas-solid dual explosion suppression mechanism of porous media cooperating with CO2 is better than that of a single porous medium, providing a theoretical reference for the composite explosion suppression technology of hydrogen-doped natural gas pipeline engineering.
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    The influence of heat conduction effect of the metal core on horizontal wire flame spread
    Zhu Xianli, Sun Xuxu
    2023, 42 (8):  1057-1062. 
    Abstract ( 258 )  
    Abstract: To investigate the heat conduction effect of the metal core on horizontal wire flame spread, this paper established the predicted model for the horizontal wire flame spread rate, and then performed the wire flame spread experiments for different thermal conductivity. In terms of the flame contour, mass loss rate(MLR) and flame spread rate, the effect of the metal core diameters and the thermal conductivity for different metal core on the wire fire were examined. With the metal core diameter increasing, the MLR firstly increases to a higher value and then decreases. Due to the higher thermal conductivity for the copper wire, a large amount of heat conduction was accumulated in the preheated area, and the MLR is higher than these of the stainless steel wire. The bigger MLR of 0.007 1 g/s is obtained for the copper inner diameter of 3.5 mm while the bigger MLR is 0.006 8 g/s for the stainless steel inner diameter of 4.5 mm. Also, compared to the stainless steel wire, the mass loss rate and the flame spread rate for the copper wire attained the bigger value. For the smaller mental core diameter, the heat conduction of the mental core from the pyrolysis area to the preheated area is relatively larger with the insulating sheath diameter increasing, and thus the flame spread velocity gradually decreases. For the mental core diameter bigger than 3.5 mm, only the insulating sheath below the metal core gets involved in the combustion and thus the larger mass loss rate is obtained, further causing a bigger flame spread rate. With the mental core diameter further increasing, the effect of heat sink for the mental core is strengthened, making the flame spread rate decrease again. Moreover, when the flame fully cover the wire, the measured flame spread velocity form the experiment is in a good agreement with the predicted velocity from the model, further verifying the adaptability of the predicted model.
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    Study on plugging schemes for cable holes in high temperature air⁃cooled reactor nuclear island
    Li Haiqing, Wang Jindong, Ding Yun, Xiao Mengnan
    2023, 42 (8):  1063-1066. 
    Abstract ( 219 )  
    Abstract: During the construction of nuclear island, cable opening and plugging is a necessary link in cable laying works, which plays an important role in maintaining the integrity of fire compartment boundary, preventing the spread of fire and preventing biological shielding. In this paper, the technical scheme of cable opening plugging for HTGR nuclear island is discussed in detail, the special requirements and solutions of high temperature reactor opening plugging are summarized, and a suit of cable opening plugging scheme which is suitable for HTGR nuclear island is put forward in order to get a good application in later engineering practice.
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    Experimental study on maximum temperature rise of smoke in point exhaust tunnel fire
    Zhang Huanhuan, Zhang Shuchuan, Zhu Ziyan, Zhao Zongyu
    2023, 42 (8):  1067-1073. 
    Abstract ( 252 )  
    Abstract: In order to explore the maximum temperature rise law of ceiling smoke in point exhaust tunnel fire, the 1∶10 experiment was conducted to study the development process of fire plume and the temperature distribution of ceiling smoke in tunnel longitudinal center line under different fire source power, fire location and smoke exhaust rate. According to the dimensional analysis method, the mathematical model of the maximum temperature rise under the ceiling is derived. The results show that the maximum temperature in the longitudinal center line of the tunnel does not change with the smoke exhaust rate, but the maximum temperature in the ceiling decreases with the increase of the smoke exhaust rate, and increases with the increase of the fire source power and the distance between the fire source and the exhaust vent. The dimensionless maximum temperature rise is proportional to the 0.034 power of the dimensionless fire location and increases with the increase of the fire source power.
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    Research on fire control effect of high pressure water mist system on Chuandou residential buildings
    Zhang Yang, Zhang Jian, Gao Xuewen
    2023, 42 (8):  1074-1078. 
    Abstract ( 241 )  
    Abstract: The excellent cooling effect of high?pressure water mist has a good inhibitory effect on early fire in buildings, which can effectively solve the problem of insufficient fire separation in wooden structures and prevent the spread of fire between buildings. In order to explore the influence of high?pressure water mist atomization cone angle, water pressure intensity, spray speed and particle size on the smoke resistance and heat insulation performance of wood structure buildings, a typical Chuandou residential building is selected as the research object, and a fire model is established by using FDS to analyze the influence of the above factors on the fire suppression effect of the wooden structure building, and the validity of the simulation results is verified by experiments. The results show that the above factors have a great impact on the fire extinguishing effect of high?pressure water mist. The simulation results show that the best fire extinguishing effect is achieved when the atomization cone angle is 120°, the spray pressure is 10.00 MPa, the spray speed is 10 m/s, and the particle size is 300 μm, which can produce the highest penetration capacity, and the fire extinguishing can be completed in 7.3 s.
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    Experimental study on the effect of transverse double fire sources spacing on critical ventilation velocity in tunnels
    Chen Haiyang
    2023, 42 (8):  1079-1083. 
    Abstract ( 234 )  
    Abstract: A 1:8 scaled test bench was built to study the critical ventilation velocity in the case of transverse double fire sources in the longitudinal ventilation tunnel. The relationship between the critical ventilation velocity and heat release rate and the distance between fire sources was studied, when two fire sources were placed symmetrically in the tunnel. The results show that the critical ventilation velocity will gradually decrease with the increasing distance between fire sources while keeping the heat release rate unchanged. In cases considered, the greater the heat release rate, the greater the critical ventilation velocity, while keeping the distance between the ignition sources unchanged; When the heat release rate increases to a certain extent, the critical ventilation velocity will not change with the increasing heat release rate, but reach a constant. The influence factor is introduced to characterize the influence of the distance between two fire sources on the critical ventilation velocity, and the critical ventilation velocity model for the transverse tunnel fire with two fire sources is established.
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    Study on the temperature field of compound concrete-filled steel tube column under fire
    Zhang Lin, Zuo Shuai, Wang Weihua
    2023, 42 (8):  1084-1089. 
    Abstract ( 207 )  
    Abstract: In order to study the temperature field variation of compound concrete-filled steel tube column during the whole process of fire rise and fall, the whole temperature field model of compound concrete-filled steel tube column was established by using ABAQUS finite element software. The results show that the inner steel tube can reduce the temperature of the inner concrete and improve the fire resistance of the concrete filled steel tube. The maximum temperature of the inner steel tube is much lower than that of the outer steel tube. Fire-resistant coating and increased section size can greatly reduce the maximum temperature of the concrete in the core area, but will not affect the maximum temperature of the outer steel pipe.
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    Experimental study of foam superimposed fire suppression technique for large methanol pool fires
    Su Zhongbo, Shen Ruiyang, Wang Yuanyuan, Hu Bokai
    2023, 42 (8):  1090-1093. 
    Abstract ( 229 )  
    Abstract: This paper validates the practical effect of foam stacking fire extinguishing method in large?scale methanol pool fires through large?scale pool fire extinguishing experiments. The main considerations are the influence of wind direction and foam mixture supply intensity on foam spreading effect and fire extinguishing rate. Meanwhile, the foam stacking fire extinguishing mechanism was analyzed, with the whole process of the experiment recorded by temperature measurement and camera equipment. The research results show that AFFF/AR stacked fire extinguishing is suitable for extinguishing methanol pool fires; the larger the supply intensity of AFFF/AR mixture and the stronger the downwind force, the faster the foam spreading and the higher the fire extinguishing rate. During the fire extinguishing process, appropriately reducing the supply intensity of AFFF/AR mixture can enhance the fire extinguishing efficiency per unit of foam concentrate and reduce environmental pollution.
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    Experimental study on entity fire test of high pressure water mist in equipment room of hub station
    Luo Man, Wang Ziyang, Chu Zhubin, Shi Xiaolong
    2023, 42 (8):  1094-1097. 
    Abstract ( 210 )  
    Abstract: In order to study the protective effect of high pressure water mist on cable fire in equipment room of rail transit hub station, a full?scale test model of equipment room of rail transit hub station was established by using the method of entity experiment, and the fire extinguishing mechanism, main design parameters and system selection were expounded. The results show that the pre?acting high?pressure water mist can effectively restrain the cable fire combustion and prevent the cable fire from spreading in the horizontal direction. After the application of fine water mist for a period of time, the ambient temperature of the test was restored to about 25 ℃, and the change range of oxygen volume fraction after the application of fine water mist was small, the lowest was 20.62%, which would not cause harm to human body. Pre?acting water mist system can reduce water damage.
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    Analysis and experimental research on air tightness test method in protection area of gas fire extinguishing system
    Zhang Wenbin , Wu qiong, Song wenqi, Gao yunsheng,
    2023, 42 (8):  1098-1102. 
    Abstract ( 279 )  
    Abstract: Gas fire extinguishing systems are often used in data rooms, battery energy storage cabins and other important places where water is not suitable for fire extinguishing. The airtightness of the protective area of the gas fire extinguishing system directly affects the success rate of fire extinguishing. In recent years, the problem of air tightness in the protective area has led to insufficient hold time, resulting in cases of fire reignition. However, the specific method of gas tightness test in the protective area of gas fire extinguishing system has not been specified in the current domestic gas engineering construction standards, which has caused an obvious lack of fire supervision. In order to ensure the reliability of the gas extinguishing system, it is urgent to test and verify the gas tightness of the gas extinguishing system protection area. This paper summarized the test methods for verifying the reliability of the protective area of the gas fire extinguishing system, comparing and analyzing the differences in the calculation models in the commonly used foreign gas tightness detection standards, and finds out through the design test that the actual concentration distribution of the air-agent interface is in the interval between NFPA 2001 and ISO 14520-1 hypothesis model, Which verified the blower door method to test the hold time.The feasibility analysis of the calculation method of peak pressure for fire extinguishing system protection is made, which provided a scientific reference for the future improvement of the gas tightness test method of the gas fire extinguishing system protection area in China.
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    Research and design of multi⁃functional fire gun virtual⁃real integration training system
    Xu Xiaoyuan, Chen Hongguang, Li Jingjing, Zhu Hongya,
    2023, 42 (8):  1103-1107. 
    Abstract ( 241 )  
    Abstract: Based on technologies such as human?machine interaction, virtual-real integration, precise fire extinguishing agent spray trajectory, and fire attenuation model, a multi?functional fire water gun virtual-real integration system is developed and designed, which can achieve simulation training of multi?functional fire water guns in different typical complex chain fire scenarios. Through experimental verification, the system can achieve accurate reproduction with an error of less than 2% for key parameters such as the height, distance and angle of the spray mode of fire extinguishing agents. It can also be closely related to the feedback of actual fire extinguishing effects, effectively improve firefighters' practical handling skills in typical complex fire scenarios.
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    An "immersed" fire protection system for electrochemical energy storage
    Chen Xianbin, Wang Yunxia, Yin Fei, Li Guoqiang
    2023, 42 (8):  1108-1112. 
    Abstract ( 432 )  
    Abstract: To ensure the safe development of the electrochemical energy storage industry, an "immersed" battery fire protection system was designed and experimented for the lithium-iron phosphate battery system. The experiment uses overcharge to trigger the thermal runaway of the battery, accompanied by the burning of open fire, and studies the fire suppression effect of the "immersed" fire protection system of the battery pack in the design fire scenarios. The experiment results show that the "immersed" fire protection system can not only extinguish the fire quickly, but also effectively inhibit the heat spread of lithium-iron phosphate battery, and ensure the safety of lithium-iron phosphate battery system.
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    Image fire detection algorithm based on YOLOv5 with CA-Res attention mechanism
    Li Xiaoxu, Li Boning, Zhang Xi, Yu Chunyu,
    2023, 42 (8):  1113-1116. 
    Abstract ( 346 )  
    Abstract: To solve the problems of low accuracy and slow speed in manual and sensor fire detection methods, based on the analysis of fire features, this paper designs an improved YOLOv5 multiplex fire detection algorithm incorporating adjustable coordinate residual attention. The YOLOv5 network adopted in our algorithm can automatically extract and learn the features of the images. First, the location information is embedded into the channel attention through the coordinate attention mechanism, which enables the network to obtain a larger range of information and improves the detection accuracy of fire images. Secondly, the initial features of the flame are retained through residual connections, and the initial features are adaptively combined with the coordinate attention features to achieve better performance. Finally, the detection and recognition with high accuracy are performed on real?time video streams captured by multiple cameras. The method proposed in this paper can identify and detect not only the flame information generated by fire, but also the smoke generated in the early stage of fire to reduce the loss of missing the best remediation time in the early stage of fire.
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    Reserch on forest fire detection base on improved YOLOv5
    Wang Naiyu, Wang Zhuo, Zhang Zichao, Wu Jinting
    2023, 42 (8):  1117-1120. 
    Abstract ( 259 )  
    Abstract: In order to improve the accuracy and speed of forest fire detection and enhance the practicability of forest fire detection model, an improved YOLOv5 forest fire detection algorithm was proposed. In this algorithm, the improved MobileViT was used as the backbone network of YOLOv5, so that the network could extract forest fire feature information more effectively. Meanwhile, in order to further reduce the complexity of the model, depthwise separable convolution was used to replace the common convolution in the model, and Mosaic data enhancement method was introduced in the training stage to improve the generalization of the model. The results show that the forest fire detection accuracy of the improved model is increased by 2.25%, mAP by 4.48%, and detection speed by 4 frames/s. Both the detection accuracy and detection speed have achieved good results. The improved model can detect forest fire well and improve the practicability of forest fire detection model. The algorithm in this paper is more competent for the task of forest fire detection.
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    Study on the flame sensor for flame arrester performance test based on ion current
    Li Beibei, Zheng Jinlei, Shen Yongxun, Liu Xiumei,
    2023, 42 (8):  1121-1125. 
    Abstract ( 215 )  
    Abstract: In the performance test experiment of flame arrester, several groups of flame sensors are installed on the pipe to monitor the arrival time of the flame, and then calculate the propagation speed of the flame in the pipe. Due to the common optical sensors are prone to false positives, easy carbon deposition, poor stability and other problems, in order to ensure the accuracy of flame speed solution, a flame sensor based on ion current is designed. The parameters of the sensor are determined through experimental comparison, that is, when the measuring electrode material is chromium zirconium copper, the electrode spacing is 2 mm, the electrode length is 25 mm, and the excitation voltage is 36 V, the sensor can reliably calculate the average flame propagation speed during the performance test of the flame arrester.
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    Design of distributed gas fire extinguishing device for substation electric gas cabinet
    Xie Dan, Li Yue, Hong Weiyi, Cao Xin
    2023, 42 (8):  1126-1130. 
    Abstract ( 237 )  
    Abstract: This article proposes a dispersed gas extinguishing fire protection system that can be used in substations, aiming to solve the problems of scattered distribution of electrical cabinets and difficult fire fighting. The fire protection system consists of modules such as fire characteristic parameter detection, fire information data transmission, gas extinguishing equipment, and fire status monitoring. The fire detection module can real-time detect arc light, temperature, smoke, and flame characteristic parameters in substations. The information collected by each module is transmitted through a one-to-many network using LoRa wireless communication technology, and all detection parameters and extinguishing status can be displayed in real-time at the monitoring end. The gas extinguishing equipment has two control modes, manual and automatic. In the automatic mode, the equipment can extinguish the fire in the electrical cabinet based on real-time fire information. The performance of the equipment has been experimentally verified through simulated fire extinguishing experiments. The results show that the fire detection accuracy of the fire protection system for dispersed electrical cabinets is reliable, and the extinguishing function can be well completed. The information exchange method is efficient and reasonable, which can provide reliable technical support for fire safety in substations.
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    Experimental study on aqueous film-forming foam extinguishment of boil-over oil fire
    Hu Cheng, Bao Zhiming, Ke Xin, Zhang Xianzhong,
    2023, 42 (8):  1131-1134. 
    Abstract ( 212 )  
    Abstract: In order to study the fire extinguishing effect and fire extinguishing mechanism of aqueous film?forming foam(AFFF) against boil?over oil fire, a small?scale boil?over oil fire test device was set up to study the fire extinguishing effect under different application rates of foam solution.The results show that when AFFF foam extinguishing agent is used to extinguish boil?over oil fire, after the foam was applied to the boil?over oil surface at high temperature, the foam disappears rapidly via the action of evaporation, the oil surface presents a violent boiling state, the flame height rises sharply, and the heat radiation intensity increases greatly. The fire extinguishing mechanism of AFFF is cooling effect. Firstly, it directly cools the surface boil?over oil temperature; secondly, it indirectly cools the bottom oil temperature through the thermal convection inside the oil. When the surface oil temperature is cooled below the spontaneous combustion point, the flame goes out. The optimum application rate of foam solution for AFFF to quench boil?over oil fire was determined as 25 L/(min·m2).
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    Experimental study on fire suppression of lithium⁃ion battery with aqueous extinguishing agent containing additives
    Hou Shuangping, Zhu Shunbing, Wang Wenhao,
    2023, 42 (8):  1135-1140. 
    Abstract ( 252 )  
    Abstract: Through the self?built test platform, the fire suppression test of ternary lithium?ion battery with water extinguishing agent containing additives was carried out. Different mass fractions of surfactant, potassium salt and microcyst fire extinguishing agent were selected to carry out the fire extinguishing test of aqueous fire extinguishing agent containing a single additive, and on this basis, three composite additive formulations were compounded, and their effectiveness in fire extinguishing of lithium?ion batteries was studied experimentally. The results show that the cooling rate and flame suppression ability of the fire extinguishing agent containing composite additive are generally better than the fire extinguishing agent containing a single additive, and the CF?2 fire extinguishing agent has the best fire extinguishing effect on ternary lithium?ion battery fire. The formula of CF?2 fire extinguishing agent was tested for physical and chemical properties and antifreeze optimization, and the optimized fire extinguishing agent formula was CF?4:SDS(1.5%),urea(0.34%),triethanolamine(0.024%),K2C2O4(1.2%),N,N?dimethylformamide(0.6%),ethylene glycol(0.3%),polyacrylamide(0.1%). Tests have shown that the formulation is not only suitable for lithium battery fire, but can be engineered under certain conditions.
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    Optimization method for fire station location based on Lagrangian relaxation framework
    Cao Yue, Li Jing, Gu Yu, Liu Han
    2023, 42 (8):  1141-1145. 
    Abstract ( 234 )  
    Abstract: Urban fires may cause serious damage to life and property, and a scientifically reasonable layout of fire stations can effectively improve fire rescue efficiency and reduce system operation costs. This study took minimizing fire waiting losses and fire station construction costs as the objectives, and uses fire truck driving time as the criterion for judging fire station coverage, constructed an integer programming model for fixed costs of fire station site selection. An exact algorithm based on the Lagrangian relaxation framework is designed, and the effectiveness of the algorithm is verified. An example optimization of fire station layout in Jinnan District, Tianjin City is conducted. Sensitivity analysis was carried out on significant parameters such as waiting loss cost and fire truck driving time, providing more accurate references for urban fire facility planning and decision making.
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    Analysis on the difficulties and countermeasures of the construction of China's nuclear power fire protection standards
    Men Changhua, Zheng Yishan
    2023, 42 (8):  1146-1149. 
    Abstract ( 232 )  
    Abstract: In order to promote the construction of nuclear power fire protection standard system in China, this paper combs and analyzes the present situation and main problems of nuclear power fire protection standards, and points out that it is technically fea sible to unify the overall fire protection standards. At the same time, it further puts forward the research focus of improving the fire protection system design and equipment standards, and pro poses to establish an information sharing platform to promote in dustry communication and research on key issues, so as to pro vide reference for the construction of nuclear power fire protection standard system in the future.
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    Thoughts on strengthening the comprehensive management of fire protection product quality
    Li Qiang
    2023, 42 (8):  1150-1153. 
    Abstract ( 250 )  
    Abstract: In response to the quality and safety issues of fire protection products, combined with our own work practice exploration, starting from guiding relevant government functional departments to strengthen political responsibility and conscientiously fulfill regulatory responsibilities, suggestions are put forward from promoting the improvement of regulations and systems for fire protection products, strengthening product inspection and testing quality certification, increasing the publicity of fire protection knowledge, mobilizing the public and consumers to participate in public safety management, and promoting the establishment of a joint prevention and control mechanism. This effectively forces production enterprises to implement the main responsibility for production quality, strive to achieve full chain supervision and management of fire protection products, and prevent and resolve the risks and hidden dangers brought by fire protection product quality, make every effort to create a safe, stable, and harmonious social environment.
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    Establishment and current situation analysis of occupational stress scale for grassroots firefighter
    Song Hang, Li Yang
    2023, 42 (8):  1154-1158. 
    Abstract ( 263 )  
    Abstract: In order to compile the occupational stress scale of grass-roots firefighter and analyze the current situation of occupational stress,a total of 1 025 domestic grass-roots firefighters were selected to carry out the research, and the project analysis, exploratory factor analysis, confirmatory factor analysis, content validity, criterion-related validity, internal consistency reliability and split-half reliability test were carried out, further descriptive analysis, t test and variance analysis were used to study the current situation of occupational stress of firefighters at the grass-roots level. The results show that the occupational stress scale for grass-roots firefighter has good reliability and validity. The scale has 27 items, including 5 factors: interpersonal relationship, work itself, occupational characteristics, personal development and external support. The overall occupational stress level of domestic grass-roots firefighter is relatively stable, and the stress scores in the three dimensions of personal development, work itself and occupational characteristics are higher. There are significant differences in occupational stress in different positions, ages, working years, educational background, marital status and so on.
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    Taking a fire as an example and discussing the whole chain investigation of fire accidents
    Gao Xiao
    2023, 42 (8):  1159-1162. 
    Abstract ( 272 )  
    Abstract: The extension investigation of fire accidents by fire rescue agencies has been comprehensively promoted nationwide, and there is an urgent need to conduct research on the accountability methods and quality supervision methods for circulation channels. This article is based on the fire of lithiumion battery electric bicycles, and systematically studies the methods and technical means of full chain investigation. Research has shown that the full chain investigation can promote the special rectification of lithium battery products in the region, improve fire risk prevention and control capabilities, make the rectification measures of industry regulatory authorities more targeted, and provide new technical means for extending the investigation.
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    Risk analysis of ammonium nitrate spontaneous combustion explosion
    Ayitila Wusiman
    2023, 42 (8):  1163-1166. 
    Abstract ( 341 )  
    Abstract: This article takes the "9·12" catastrophic explosion accident in Mile county as an example to analyze the direct causes of the accident and use the fault tree method to identify the root cause of the accident. Frank-Kamenetskii thermal spontaneous combustion theoretical model was used to study the explosion mechanism of ammonium nitrate. It was found that impurities would reduce the self-accelerating decomposition temperature of ammonium nitrate, and eventually lead to thermal explosion of ammonium nitrate. Finally, some suggestions on the storage and transportation of ammonium nitrate are given.
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