水喷雾系统抑制电动汽车火灾有效性实验研究

为解决现有消防手段难以有效扑灭电动汽车火灾的问题,设计了水喷雾隔热阻火系统和拖车式车载水喷雾灭火降温系统.对模拟电动汽车火灾进行灭火有效性全尺度实验.结果表明,在现有工况条件下,水喷雾隔热阻火系统能有效抑制车辆底盘的射流火焰,可防止火灾向相邻车辆蔓延,但受安装位置限制,该系统对驾驶舱内部火焰的抑制和降温效果较差,灭火后...     

自动跟踪定位射流灭火装置安装施工技术

针对高层建筑存在的消防隐患,提出了自动跟踪定位射流灭火装置系统,介绍了该装置的技术特点及使用范围,着重阐述了其施工工艺流程及要点,指出该装置可以对早期火灾进行自动跟踪定位,并运用自动控制方式实现射流灭火,达到预防火灾效果。     

压缩空气喷雾灭火系统

介绍了日本研制的新型节水灭火系统——压缩空气喷雾灭火系统的研究背景，以及灭火系统的组成和特点，讨论了喷雾水枪的灭火性能和喷嘴设计及试验，并分析了便携式、背负气瓶式、手推车式和车载式等实用型压缩空气喷雾灭火系统的研制，以及灭火系统的发展现状和应用前景。     

消防新技术新产品

1 公共交通车辆消防安全防护系统 最近,四川省消防总队研制出了一种“公共交通车辆消防安全防护系统”。该系统由保护客舱的喷雾灭火系统和保护发动机舱的超细干粉灭火系统组成。其中,客舱的喷雾灭火系统由控制装置、电源转换装置、灭火剂贮存装置等组成;发动机舱系统则由控制装置和悬挂式脉冲超细干粉灭火装置组成。火灾时,这种公交防护系统能在5s内响应启动,1min内扑灭火灾。     

日本产、学、官联合研发喷水装备——关于利用2流体混合喷雾装置进行灭火的喷水装备

1开发的背景 用水灭火效果好，没有毒副作用，对环境没有污染，而且成本低等优点。但是，对于高层住宅发生火灾喷水灭火时，由于容易造成漏水现象，因而不可避免地发生水害，因此，水害现象作为严重的社会问题倍受关注。既要减少水害，消防员又能有效地实施灭火，这样，就要寻求一种用少量的水就能有效地进行灭火的方法。为了达成此目标，手段之一就是如何把水喷雾方法应用到灭火中去。为此，有必要研究、开发、试验一种适用于消防员使用的可搬性强，操作灵活的喷雾喷嘴，而且这种新开发的喷雾喷嘴应具有实用性、减少水害、灭火能力强等特点，还有必要在苛刻的条件下，对其进行反复验证。因此，为了解决本课题，具有能把水喷雾技术的三菱重工业股份有限公司，一直致力于降低水害研究的横滨市消防局和从事灭火技术研究的消防研究所，共同研发喷雾喷嘴。     

惰性气体灭火系统喷嘴流量特性的数值仿真

在灭火系统构建中,利用相关计算流体力学中的信息数据 FLUENT 软件,对惰性气体灭火系统喷嘴的流量特性进行计算, FLUENT软件能够对喷嘴中惰性气体灭火系统的高速、高压湍射流流场的数值进行有效的计算仿真,得到惰性气体灭火系统中各种喷嘴时射流的压力、温度、速度等一系列的流场参数值,在这一基础上,计算出不同压力作用下喷嘴流量的参数值,有效的对不同喷嘴在可压缩的环境下所具备的喷嘴流量特性数值进行仿真.     

无水快速自动灭火装置在陕西问世

一种将航天技术中的超音速技术成果应用于消防系统的无水快速自动灭火装置，日前在西安通过了国家经贸委委托国家烟草专卖局组织的应用鉴定。鉴定委员会认为，这一系统技术含量高，属国内、国际首创。陕西兰德森茂消防科技有限公司研制的固定式燃气型超音速干粉自动灭火系统，应用固体火箭发动机原理研制成以干粉为灭火剂的先进消防装置。一旦接到火警信号，这种装置采用超音速燃气发生器产生高速射流，同时高速射流使干粉进一步细化，一般在干粉喷出的瞬间即可灭火，而且形成固相、气相混合的保护空间，可以控制火灾蔓延。与常规灭火技术产…     

基于热敏绝缘材料的电气柜区块式自灭火装置研究

为更好地解决电气柜火灾发展速度快、灭火难度大等问题，基于热敏绝缘材料构建了1 种集精准探测与可靠灭火于一体、安装简易、可重复使用的电气柜区块式自灭火装置。通过对电气柜火灾热点区域的分析，确定热敏绝缘材料布置方案，并进行了相关灭火试验。结果表明，该自灭火装置在多种工况下都能较快扑灭电气柜火灾。线缆火试验中装置在20~35 s 内实现灭火；较大规模火灾试验中在29~37 s 内实现灭火；多位置起火试验中在18~75 s 内实现灭火。重复性灭火试验表明该装置具有良好的重复使用能力。     

浅析微细水雾灭火系统的技术性能优势

阐述了微细水雾灭火系统的工作原理及组成。将微细水雾灭火系统与普通灭火系统进行比较。从喷嘴设计、喷雾强度、喷雾时间、水滴作用面积等多方面,介绍了微细水雾灭火系统的优势及应用前景。     

水喷雾应用探讨

提出了移动式水喷雾灭火系统的概念 ,建议将其应用在火电厂或变电站 ,扑救可能产生的带电火灾的消火栓系统上。     

熄灭森林阴燃火的细水雾喷头设计与仿真

森林大火后的残余地表余火及地下阴燃火是引起二次森林火灾的主要原因,为防止发生二次森林火灾,清理森林余火和阴燃火是必要的.细水雾作为哈龙灭火剂的最佳替代品,被广泛应用在消防领域.本文设计一种适合熄灭森林余火和阴燃火的撞击分流高压细水雾喷头,采用Fluent进行喷头流域的仿真,分析喷孔孔径、喷孔长度和喷孔喷雾锥角对喷出细水...     

一种低压中速离心式水雾喷头的开发和实验研究

根据对喷头结构参数的理论计算，设计了一种低压中速离心式水雾喷头，并与目前常见的低压高速水雾喷头进行了灭火实验效果比较，结果表明新设计的水雾喷头能更好抑制和扑灭A类火、B类火及AB类混合火，并节省用水量。     

Experimental and numerical study of high-pressure water-mist nozzle sprays

The performance of extinguishment of fires by water sprays is strongly influenced by the characteristics of the sprays produced by nozzles. Computational fluid dynamics (CFD) based fire models are a tool that can be used for the characterization of sprays. However, it is necessary to evaluate the capability of a CFD based fire model in predicting the behaviour of sprays before using it for such characterization. One of the basic parameters that is important in characterising the water mist spray is the distribution of flux density of water droplets impinging on the floor. This paper reports the study on the characterization of water mists, in terms of distribution of flux density of sprays, produced by a single and a multi-orifice high-pressure jet nozzle. Full-scale experiments were conducted and the distributions of volume flux density of sprays were measured. The sprays were also modelled using a CFD model, Fire Dynamic Simulator (FDS), version 6, to investigate the capability of the model in predicting the distribution behaviour of the spray. The numerical results of distribution are compared with those obtained experimentally. The predicted results of FDS has show good agreement with the experimental results.     

Robotic Fire Suppression Through Autonomous Feedback Control

A computer vision-based autonomous fire suppression system with real-time feedback of fire size and spray direction is presented in this paper. The system has been developed for use in a firefighting robot for close-range, localized fire suppression tasks in enclosed environments. A probabilistic water classification method was developed for segmenting water spray in a pair of IR cameras. Stereo processing was performed to localize points along the spray path for use in yaw and pitch angle estimation. A Golden Section Search with linear least squares optimization was used to determine the optimal pitch angle of the spray position at each sampling time. Kalman filtering was used to remove noise from the angle measurements and obtain a better estimate of the current nozzle orientation. A decision tree was used to determine the correct nozzle positioning mode using image feedback to suppress the fire and accounts for errors in direction, fire size during suppression, and when to adjust the nozzle based on IR feedback. Through implementation of a PI controller, the system is able to correct for unknown disturbances causing erroneous targeting of a localized fire. Experiments are presented with the initial nozzle angled correctly and with forced offsets in the system to set the initial spray position incorrectly in order for the system to correct. Suppression times ranged from 7.2 s to 16.3 s with a standard deviation of 3.9 s and average time of 11.2 s. A total of 12 tests demonstrated performance of the system given a forced offset to the initial nozzle orientation resulting in an error between the spray location and the fire target. Suppression times ranged from 8.1 s to 27.9 s with a mean of 16.9 s and standard deviation of 6.2 s. The proposed system can be implemented on a robotic firefighting platform to autonomously detect a fire, choose a proper manipulation goal and suppress full scale fires given disturbances causing erroneous targeting.     

Physical scaling of water mist fire extinguishment in industrial machinery enclosures

Froude-based scaling relationships had previously been theoretically extended to, and experimentally validated in the laboratory for, water mist suppression of fires in open environment and in enclosures, which were shown applicable to gas, liquid and solid combustible fires. Before applying these relationships to real-world settings, their applicability needs to be further evaluated for the intended protection. This paper presents such an evaluation on scaling water mist fire extinguishment in an industrial machinery enclosure. In this evaluation exercise, a full-scale water mist protection set-up tested for a 260-m³ machinery enclosure was selected as the benchmark. A ½-scale machinery enclosure test replica was then constructed, together with a ½-scale nozzle whose orifices were geometrically similar to those of the full-scale nozzle. Spray measurements indicated that the ½-scale spray closely met the scaling requirements, in terms of discharge K-factor, water mist flux, droplet velocity and droplet size distribution. Two spray fires and one pool fire, which were scaled with the respective full-scale fires, were used to challenge the water mist protection in the ½-scale enclosure. At least five replicated tests were conducted for each of the four tested fire scenarios. Overall, the instantaneous local gas temperature and oxygen concentration measured inside the ½-scale enclosure for each fire scenario agreed reasonably well with those measured at the corresponding locations inside the full-scale enclosure, meeting Froude modeling's requirement that scalar quantities be preserved in different scales. The fire extinguishment times obtained from the ½-scale tests for each fire scenario were also statistically consistent with that observed in the corresponding full-scale test. Based on the obtained results, it is concluded that, for machinery enclosures and other similar occupancies, the previously laboratory-validated scaling relationships for water mist fire suppression can be used to determine the fire extinguishing performance of a full-scale water mist protection in a ½-scale test facility.     

固定式压缩空气泡沫系统单喷头喷洒特性及灭火效能

对5 种典型结构喷头进行了单喷头喷洒压缩空气泡沫和纯水试验,对喷洒介质在底面上的密度分布以及喷洒的泡沫25%析液时间进行比较分析。研究发现,喷头结构类型和流动参数都会影响泡沫析液特性,喷头内部旋芯会使泡沫稳定性降低;下垂式水喷头的底面分布均匀性较好,而扰流喷头和两种七孔喷头的底面分布均匀性相对较差,且下垂式水喷头和扰流喷头在更高的压力和流量条件下的底面分布均匀性降低;同时,压缩空气泡沫系统的喷头选型可以在一定程度上参考相应喷头的喷水特性。选用最优性能参数喷头,建立火灾模型,开展固定式压缩空气泡沫系统全尺寸变压器热油火灾试验,验证喷头与固定式系统的适配性。     

Development of a computational model simulating the interaction between a fire plume and a sprinkler spray

Numerical simulations to predict actual delivered densities (ADDs) of early suppression fast response (ESFR) sprinklers in heptane spray fire scenarios were sought. First, in order to supply input data for the development of numerical models and experimental data for validation of the models, four sets of measurements were carried out: the momentum and water flux distribution of two ESFR sprinkler sprays without fire; the temperature and axial velocities along the axis of free-burn fires; and the actual delivered densities. Then, a numerical model for a sprinkler spray was completed by assigning the representative drop size, mass flow rate, discharge speed and discharge angle of 275 trajectories in such a way that they produced reasonable agreement with the measured water flux distribution and spray momentum in the absence of fire. A numerical model for the free-burn fire was created by assigning a heat flux distribution on a horizontal surface and simulating a central, vertical air jet used in the experiment, varying parameters until a reasonable match was established with the measured temperatures and the axial velocities along the axis. Numerical computations of actual delivered densities were carried out by combining the water spray model and the free-burn fire model for different water flow rates of the sprinklers. The ADDs obtained from the simulations compared reasonably well with those from the measurements.     

大功率雾状水消防装备--涡喷消防车

利用喷射功率达4000kW的航空涡轮喷气发动机产生的大流量、高流速气体射流,与大流量的水射流混合,形成高流速“气体一水雾两相射流”的涡喷消防车,使雾状水的喷射距离大幅度增加,将大流量水雾射流或轻水泡沫微珠射流沿水平方向快速射入火焰中。分析了涡喷消防车的工作原理及雾状水消防车喷射功率大、控制火势能力强、灭火速度快的特点。