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干粉灭火剂和水爆炸驱动下运动特性及灭火效果对比分析
Comparative analysis of kinematic characteristics and fire extinguishing effect between dry powder extinguishing agent and explosion driven water mist
 [PDF]

汪泉,李成孝,李志敏,郭子如,程扬帆,李雪交
- , 2018, DOI: 10.7520/1001-4888-17-221
Abstract: 爆炸驱动的干粉灭火剂或水灭火相对于传统灭火方式具有高效、便捷等优势,可应用于森林、草原和高层建筑物等火灾扑救。为了研究干粉和水介质爆炸运动特性及其灭火效果,采用HX-3型彩色高速摄像机记录爆炸水雾、爆炸抛撒干粉灭火剂灭火的全过程,发现爆炸装置直径、介质质量对两类介质爆炸抛撒过程、抛撒半径、抛撒作用时间有着显著影响;等体积的干粉和水进行爆炸灭火,水介质到达着火区域较快,而干粉驻留时间较长。文中的实验结果与分析,对提高爆炸灭火效率、优化水基或干粉基爆炸灭火弹结构,具有一定的理论参考价值。
Compared with traditional fire extinguishing methods, explosion driven dry powder fire extinguishing agent or water mist has the advantages of high efficiency and convenience, etc. It can be applied in forest, grasslands and high-rise building fire put out. In order to study the kinematic characteristics and fire extinguishing effect of two typical extinguishing agents, the whole process of water mist and powder disperse in extinguishing was recorded by HX-3 type high speed colour video camera. It is found that the diameter of explosion device and agent mass have significant influence on the explosive dispersal process, the dispersion radius and spreading time of two kinds of media. When the same volume of dry powder and water were used to extinguish fire, the water medium reached the fire ignition area faster, and the dry powder remained for a longer time. Experimental results and analysis in this paper have certain theoretical reference value for improving fire-extinguishing efficiency and optimizing the structure of water-based or powder-based explosion extinguishing projectiles
Improvement of Fire Extinguishing Performance by Decentralized Supply of Fire-Fighting Agents  [PDF]
Yasushi Iwatani, Hiroyuki Torikai
Open Journal of Safety Science and Technology (OJSST) , 2017, DOI: 10.4236/ojsst.2017.73008
Abstract: One of the central problems in fire safety science and technology is to reduce damage caused by both fires and fire-fighting processes. This paper provides a potential solution to the problem, and it derives from decentralization of fire-fighting agents. In particular, this paper investigates fire extinguishing performance when a fire-fighting agent is supplied to a fire from one direction with one extinguisher and from two directions with two extinguishers. The two methods are called the centralized supply and the decentralized supply, respectively, in this paper. It is demonstrated that the decentralized supply reduces damage caused by both fires and fire-fighting processes. This follows from the facts that fire extinguishment by the decentralized supply is more certain than the centralized supply, and that the decentralized supply requires less total amount of a fire-fighting agent than the centralized supply for fire extinguishment.
Evaluation of Aerosol Fire Extinguishing Agent Using a Simple Diffusion Model
Chen-guang Zhu,Chun-xu Lü,Jun Wang
Mathematical Problems in Engineering , 2012, DOI: 10.1155/2012/873840
Abstract: Aerosol fire extinguishing agents have been recognized as an effective replacement of Halon. The uniform diffusion time and the effective concentration of the aerosol fire extinguishing agent are important parameters for putting out a fire. In this work, the effective concentration is derived based on the diffusion equation, and its variation with changing diffusion coefficient and diffusion time is analyzed. The uniform diffusion time could then be conveniently estimated using this equation. Based on experimental data, the concentration kinetics of the aerosol is drawn and the relation between the diffusion coefficient and the uniform diffusion time is analyzed. It was found that the uniform diffusion time is not dependent on the shape of the closed room but dependent on the total room volume and the position of its diffusion source. This model is demonstrated as a facile tool for the convenient evaluation and reasonable application of the aerosol fire extinguishing agent by predicting the uniform diffusion times of extinguishing aerosol in closed rooms.
Opening-up of Forests for Fire Extinguishing Purposes  [PDF]
Andrea Majlingová
Croatian Journal of Forest Engineering , 2012,
Abstract: Information on the existence of forest roads as well as their quality is important not only for planning forest management activities, but also for fire management, which includes fire risk assessment and fire suppression. In the case of fire, the level of forest opening-up has a significant influence on the attendance time of fire brigades. Not sufficiently developed road network is often reflected on the elongation of fire-fighting attack and exactingness of shuttle water relay. Therefore, the level of forest opening-up is an important indicator and factor affecting the promptness of fire-fighting activities and further fire spreading, because forest roads also represent a natural barrier against fire. A simple approach to the assessment of the level of forest opening-up has been introduced from the aspect of terrain accessibility for the available mobile fire apparatus with the use of GIS and GNSS technologies. First, the forest road network was mapped using the GNSS technology, and then the information on the quality of particular roads was collected. These data were processed in the ArcGIS 9.3 environment and as a result the geodatabase was created. It was later used to process the opening-up analysis in IDRISI Taiga environment. The opening-up analysis was performed for the Hrabusice forest management district, located in the karst area of the Slovensky raj National Park and the available mobile fire apparatus – pumping appliance CAS 32 on Tatra 148 chassis and forest special UNIMOG on Mercedes chassis. The objective of the opening-up analysis was to identify the zone where the terrain is accessible for mobile fire apparatus and where fire hose piping is admissible. It was based on computation of the maximum range of fire hose piping (maximum sidelong distance), road spacing and the index of forest opening-up. The results of this analysis are valuable as a support for decision making for foresters dealing with forest protection, road planning and construction, for fire brigades in planning fire attacks, as well as for risk managers and crisis managers.
Effects of water mist addition on kerosene pool fire
XiaoMeng Zhou,Jun Qin,GuangXuan Liao
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-008-0437-8
Abstract: The use of water mist to extinguish fire is a problem of particular interest since the banning of halogen-based agents for environmental reasons. This interest is reflected in the large number of researches performed on the main fire-extinguishing mechanisms of water mist: heat extraction, oxygen displacement and attenuation of heat fluxes. In contrast, there are still little known about the chemical and some other aspects of water mist addition on the pool fire. In this paper, a phenomenological study was conducted of the effect of water mist addition on the kerosene pool fire through the measurement of the heat release rate, CO, CO2 and O2 species concentration in combustion. The experimental results show that there is a significant enhancement effect at the beginning stage of water mist addition. Then, the flame size was decreased abruptly. By physical suppression effect combined with chemical effect, the experiments’ results are explained especially. The study of effects of water mist on pool fire will be useful for optimizing designation of water mist fire-suppression system, improving the fire suppression efficiency and extending their application field.
Experimental study on fire extinguishing with a newly prepared multi-component compressed air foam
XiShi Wang,YaoJian Liao,Lin Lin
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-008-0571-3
Abstract: A multi-component compressed air foam system (MCAFS) was developed with newly prepared multi-component foaming agents. Extinguishing of wood crib and oil pool fires was performed under different conditions, such as foam concentration, mixing chamber forepart structure and working pressure. It was found that the foam concentration had sufficient effects on fire extinguishing efficiency, and an optimized concentration value exists. For instance, for diesel oil pool fires, this value is about 2.2% while it is about 4.0% for wood crib fires. The results also show that the system with a coaxial mixing chamber has greater efficiency than a T-shape. The effects of working pressure on fire extinguishing are evident in experiments, i.e., the higher the working pressure is, the more readily the fire is extinguished.
Development of the system of the decision support for head of fire extinguishing based on the adaptive neural fuzzy inference systems (anfis) during the fire on the territory of seaport  [PDF]
Kiper Alexander Victorovich,Stankevich Tatiana Sergeevna
Vestnik Astrahanskogo Gosudarstvennogo Tehni?eskogo Universiteta. Seria: Upravlenie, Vy?islitel?naa Tehnika i Informatika , 2013,
Abstract: The features of substantiation and development of the decision support system for the head of fire extinguishing are considered. The system is intended to improve the reliability of management decisions in predicting the dynamics of the fire spread and in determining the necessary fire fighting forces and equipment under uncertainty. For definition the dynamics of the fire spread and the necessary fire fighting forces and equipment the approach based on the Adaptive Neural Fuzzy Inference Systems (ANFIS) is offered. During the development of the decision support system input parameters were selected using the method of expert assessment and were evaluated. A database, which enables users to store and use data in predicting the dynamics of the fire spread and in determining the necessary fire fighting capabilities, is created. The database replenishment by the user in the course of work is realized. The task of forming the training samples for the system is solved. The results of predicting the spread of dangerous effects of fire and determination of necessary for localization and liquidation forces and equipment are evaluated.
Experimental study on fire extinguishing with a newly prepared multi-component compressed air foam

XiShi Wang,YaoJian Liao,Lin Lin,

科学通报(英文版) , 2009,
Abstract: A multi-component compressed air foam system (MCAFS) was developed with newly prepared multi-component foaming agents. Extinguishing of wood crib and oil pool fires was performed under different conditions, such as foam concentration, mixing chamber forepart structure and working pressure. It was found that the foam concentration had sufficient effects on fire extinguishing efficiency, and an optimized concentration value exists. For instance, for diesel oil pool fires, this value is about 2.2% while it is about 4.0% for wood crib fires. The results also show that the system with a coaxial mixing chamber has greater efficiency than a T-shape. The effects of working pressure on fire extinguishing are evident in experiments, i.e., the higher the working pressure is, the more readily the fire is extinguished. Supported by the Natural Science Foundation of China (Grant No. 50774072), National Key Technology R&D Program (No. 2006BAK06B07) and Program for New Century Excellent Talents in University (No. NECT-07-0794)
CONCEPT DESIGN AND TESTING OF MULTI-NOZZLE WATER MIST FIRE SUPPRESSION SYSTEM
Danardono A. Sumarsono,Yulianto S. Nugroho,Mariance,I Gede Wahyu W. Ariasa
Makara Seri Teknologi , 2010,
Abstract: In this work a flexible design of multi-nozzle arrangement of water mist fire suppression system was studied. The source of fire was a 65 mm diameter cooking oil fire. An investigation on the impact of nozzle arrangement on the temperature profile of fires was conducted. The occurance of oil splash due to the application of water mist was also studied. The water mist systems developed in the present work can effectively extinguish cooking oil fires and prevented them from re-ignition. The spray angle, discharge pressure, and water flow rate were important factors to determine the effectiveness of water mist in extinguishing cooking oil fires.
Suppress flashover of GRP fire with water mist inside ISO 9705 Room  [cached]
Qiang Xu,Gregory j Griffin,Xinggui Que,Liying Cao
Thermal Science , 2011, DOI: tsci1102353x
Abstract: Water mist suppression tests for glass-reinforced polyester (GRP) panels were conducted in ISO 9705 room. GRP panels covered part of the room and a wood crib fire was used as fire source to ignite GRP fire. A four-nozzle water mist suppression equipment was used inside test room on the time of flashover. Heat release rate of the combustion inside the room, room temperature, surface temperature of GRP panels, total heat flux to wall, ceiling and floor in specific positions were measured. Gas concentration of O2, CO, and CO2 was also measured in the corner of the room at two different levels. A thermal image video was used to record the suppression procedure inside room. Test results show that the water mist system is efficient in suppressing the flashover of GRP fire and cooling the room within short time.
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