人类越来越重视安全，且高效灭火技术一直是安全领域的重大需求。泡沫是消防领域主要灭火技术之一，尤其是近些年，压缩空气泡沫系统获得广泛应用，该技术虽灭火效率较高，但设备多依赖于国外进口，存在成本高和维修保养不便等问题；且压缩空气泡沫里含空气，会增加火场氧含量。若将泡沫中的压缩空气换为惰性气体，研发新型泡沫灭火系统，突破技术瓶颈，形成自主知识产权，这有利于打破国外在高端泡沫灭火领域的技术垄断。本文结合二氧化碳气体和泡沫的灭火优势，设计搭建二氧化碳泡沫灭火系统，开展二氧化碳泡沫性能实验研究，并对系统结构和参数进行优化。

本文设计的二氧化碳泡沫灭火系统主要由CO₂气源供给系统、水罐、泡沫液罐、泡沫发生装置和控制系统五部分组成。首先采用T型混合腔的泡沫发生装置进行发泡，研究气液质量流量比L_GCO2 /L_foam、有无筛网和筛网目数对二氧化碳泡沫特性表征的影响。发现当泡沫发生装置中未添加筛网时，随着L_GCO2  /L_foam增加，3%高倍泡沫溶液下的二氧化碳泡沫发泡倍数高于有筛网下的泡沫，但泡沫稳定性低于有筛网下的泡沫；此外，分析了两种泡沫溶液下二氧化碳泡沫的析液特性差异。

其次，开展小尺寸实验研究并分析了两种泡沫溶液下二氧化碳泡沫的灭火与抗烧性能和过程。对于3%水成膜泡沫溶液下的二氧化碳泡沫，研究表明在相同筛网目数下，L_GCO2  /L_foam越小，泡沫控火与灭火效能越强，但抗烧性能越弱；在相同L_GCO2  /L_foam配比下，泡沫发生装置中有无筛网对泡沫灭火时间几乎无影响，但对泡沫抗烧性能影响较强。对于3%高倍泡沫溶液下的二氧化碳泡沫，研究表明在相同筛网目数下，泡沫成功灭火存在临界气液质量流量比 L_GCO2 /L_foam=0.017；在固定 L_GCO2 /L_foam配比下，泡沫发生装置中有无筛网和筛网目数对泡沫灭火时间影响较大，对泡沫抗烧性能影响较弱。

最后，对泡沫发生装置中气液混合腔和扰流器类型进行了结构改进和参数优化。通过实验研究气液流动方向和扰流器类型对二氧化碳泡沫发泡倍数、稳定性、析液特性以及均匀性的影响；研究发现当泡沫发生装置中气液流向与重力方向相反，且含有丝网扰流器时发泡效果最好，且当 L_GCO2 /L_foam=0.004时，泡沫喷射连续且铺展速度快，发泡倍数为9，泡沫半衰期可达9 min。

本文研究成果对后续研发二氧化碳泡沫灭火系统具有重要参考价值和工程意义。

Human beings pay more and more attention to the safety, and the efficient fire extinguishing technology is always important demand in the safety field. Foam is one of the main fire extinguishing technologies in the fire-fighting field, especially in recent years, the compressed air foam system is being widely used. Although this technology has the higher fire extinguishing efficiency, most of their devices is imported from abroad. There are problems such as high cost and inconvenient maintenance; and compressed air foam contained air will increase the oxygen content in the fire. If the compressed air in the foam is replaced with an inert gas, a new foam fire extinguishing system is developed, we break through the technical bottleneck and form independent intellectual property rights, which will be conducive to breaking the technological monopoly of foreign countries in the field of high-end foam fire extinguishing. Combined the fire extinguishing advantages of carbon dioxide and foam, this paper designed and built a carbon dioxide foam fire extinguishing system, carried out experimental research on carbon dioxide foam performances, and optimized the structure and parameters of the system.

The carbon dioxide foam fire extinguishing system designed in this paper is mainly composed of five parts: CO₂ gas source supply system, water tank, foam concentrate tank, foam generator and control system. First, this paper designed a foam generator with a T-shaped mixing chamber to produce foam, and studied the influence of L_GCO2 /L_foam ratio (mass flow ratio of CO₂ gas and foam solution), with and without screen mesh, and the mesh number of screen mesh on the property characterization of carbon dioxide foam. It was found that when the foam generator was without screen mesh, as the L_GCO2 /L_foam ratio increased, the foam expansion ratio of carbon dioxide foam under the 3% high expansion foam solution was higher than that under the foam generator with screen mesh, but the foam stability is lower than the foam under foam generator with the screen mesh. In addition, this paper also analyzed the drainage characteristic difference of the carbon dioxide foam under the two foam solutions.

Then, small-scale experiments were carried out to study and analyze the fire extinguishing and burnback properties and processes of carbon dioxide foam under the two foam solutions. For carbon dioxide foam of under 3% aqueous film-forming foam solution, the research has showed that under the same screen mesh, the smaller the L_GCO2/L_foam ratio is, the stronger the foam fire control and extinguishing efficiency is, but the weaker the foam burnback property is. At the same L_GCO2 /L_foam ratio, there is almost no effect on the foam fire extinguishing time with or without screen mesh in the foam generator, but it has a strong influence on the foam burnback property. For carbon dioxide foam of under 3% high expansion foam solution, studies have shown that under the same screen mesh number, the critical gas-liquid mass flow ratio L_GCO2/L_foam=0.017 exists for foam successful fire extinguishing. At the constant L_GCO2/L_foam ratio, with and without screen mesh and the mesh number of screen mesh in the foam generator have great influence on the fire extinguishing time of the foam, and have little influence on the burnback property of the foam.

At last, this paper carried out the improved structure and optimized parameters of the gas-liquid mixing chamber and the spoiler type in the foam generator. By carrying out experimental research on the effects of the flow direction of gas-liquid two phase flow and the spoiler types on the foam expansion ratio, stability, drainage characteristics and uniformity of carbon dioxide foam. It was found that the foaming effect was the best when the gas-liquid flow direction is opposite to the gravity direction and the screen spoiler is used; and when the system parameter was set to L_GCO2/L_foam=0.004, the foam injection was continuous, the spreading speed was fast, the foam expansion ratio was 9, and the foam half-life was 9 minutes.

The research results of this paper have important reference value and engineering significance for the subsequent development of carbon dioxide foam fire extinguishing system.

[1]傅智敏. 我国火灾统计数据分析 [J]. 安全与环境学报, 2014, 14(6): 341-345.

[2]应急管理部消防救援局. 2019年全国接报火灾23.3万件起 [EB/OL]. https://www.119.gov.cn/article/3xBeEJjR54K, 2020-02-26 /2021-03-15.

[3]应急管理部消防救援局. 2020年全国火灾及接处警情况 [EB/OL]. https://www.119.gov.cn/article/41kpo4CAQyv, 2021-02-01/2021-03-15.

[4]吴海涛, 柳华, 李志强, 等. 哈龙替代灭火剂环保及毒性研究进展 [J]. 航空维修与工程, 2020(07): 37-40.

[5]高阳. 压缩空气泡沫灭火性能及机理研究 [J]. 消防科学与技术, 2016, 35(04): 532-536.

[6]杨小山. 大型储油罐区火灾扑救对策研究 [J]. 消防技术与产品信息, 2018, 31(06): 21-24.

[7]杨亮. 灭火剂与其标准化 [M]. 北京: 科学技术文献出版社, 2015: 1-3.

[8]GB27897-2011. A类泡沫灭火剂 [S]. 北京: 中国标准出版社, 2011.

[9]Kim A.K., Crampton G P. Evaluation of the fire suppression effectiveness of manually applied Compressed-Air-Foam (CAF) system [J]. Fire Technology, 2009, 48(3): 549-564.

[10]Magrabi S A, Dlugogorski B Z, Jameson G J. Bubble size distribution and coarsening of aqueous foams [J]. Chemical Engineering Science, 1999, 54(18): 4007-4022.

[11]Magrabi S A, Dlugogorski B Z, Jameson G J. A comparative study of drainage characteristics in AFFF and FFFP compressed-air fire-fighting foams [J]. Fire Safety Journal, 2002, 37(1): 21-52.

[12]Sheng Y J, Jiang N, Sun X X, et al. Experimental study on effect of foam stabilizers on aqueous film-forming foam [J]. Fire technology, 2018, 54(1): 211-228.

[13]牟小冬, 郎需庆, 尚祖政, 等. 液氮泡沫灭火系统研发 [J]. 安全、健康和环境, 2019, 19(07): 52-55.

[14]牟善军, 郎需庆, 牟小冬, 等. 大流量液氮泡沫灭火系统应用探究 [J]. 劳动保护, 2019(01): 18-21.

[15]郎需庆, 姜春明, 吴京峰, 等. 大型罐区构建大流量液氮泡沫系统的探讨 [J].消防科学与技术, 2020, 39(07): 952-954.

[16]Hurley M J, Gottuk D T, Hall J R, et al. SFPE handbook of fire protection engineering [M]. Springer, 2015.

[17]Butler J N. Carbon dioxide equilibria and their applications [M]. Routledge, 2019.

[18]宋广瑞, 但学文, 刘静. 气体灭火系统 [M]. 成都: 西南交通大学出版社, 2015.

[19]GB50193-93. 二氧化碳灭火系统设计规范(2010版) [S]. 北京: 中国标准出版社, 2010.

[20]彭磊, 何文敏, 畅亚文, 等.压缩空气泡沫系统及其产泡特性研究 [J]. 隧道建设(中英文), 2019, 39(11): 1815-1822.

[21]James E L. NFPA-11: Standard for low-, medium-, high-expansion foam [S]. National Fire Protection Association, 1998.

[22]林霖, 翁韬, 房玉东, 等. 压缩空气泡沫析液过程分析 [J]. 中国科学技术大学学报, 2007, 37(1): 70-76.

[23]魏永建, 丛林, 张传宝. 压缩空气泡沫灭火系统原理及在德国曼底盘消防车上的应用 [J]. 消防技术与产品信息, 2017(05): 60-63.

[24]邓天刁, 刘长春, 黄林远, 等. 正压式泡沫灭火技术的研究进展 [J]. 中国安全科学学报, 2019, 29(10): 64-70.

[25]智会强. 低沸点可燃液体储罐火灾有了克星-公安部天津消防研究所发明七氟丙烷气体泡沫灭火技术 [J]. 中国消防, 2013(06): 47-48.

[26]GA 1288-2016. 七氟丙烷泡沫灭火系统 [S]. 北京: 中国标准出版社, 2016.

[27]Kim A.K., Crampton G P. Use of compressed-air foam technology to provide fire protection for power transformers, Report B-4142.1 [R]. Institute for Research in Construction, National Research Council of Canada, Ottawa, ON, 2004.

[28]Dlugogrski B Z, Schaefer T H, Kennedy E M. Verifying consistency of effective-viscosity and pressure-loss data for designing foam proportioning systems [R]. NIST SP984-3, National Institute of Standards and Technology, 2005.

[29]Rie D H, Lee J W, Kim S. Class B fire-extinguishing performance evaluation of a compressed air foam system at different air-to-aqueous foam solution mixing ratios [J]. Applied Sciences, 2016, 6(7): 191.

[30]Laundess A J, Rayson M S, Dlugogrski B Z, et al. Suppression performance comparison for aspirated, compressed-air and in situ chemically generated class B foams [J]. Fire technology, 2012, 48(3): 625-640.

[31]Rappsilber T, Kr Ger S. Design fires with mixed-material burning cribs to determine the extinguishing effects of compressed air foams [J]. Fire Safety Journal, 2018, 98: 3-14.

[32]傅学成, 陈涛, 胡成, 等. 不同类型压缩空气泡沫灭隧道油池火性能比较 [J]. 消防科学与技术, 2017, 36(11): 1563-1567.

[33]王喜世, 廖瑶剑, 林霖. 一种新制备的多组分压缩空气泡沫灭火实验研究 [J]. 科学通报, 2008, 53(19): 2379-2383.

[34]Wang X S, Liao Y J, Lin L. Experimental study on fire extinguishing with a newly prepared multi-component compressed air foam [J]. Chinese Science Bulletin, 2009, 54(3): 492-496.

[35]王淮斌. 一种正压式低倍数泡沫发生装置的研发 [J]. 消防科学与技术, 2018, 37(1): 51-53.

[36]程婧园, 张玉斌. SK标准静态混合器应用于压缩空气泡沫系统的可行性研究 [J]. 火灾科学, 2018, 27(1): 38-45.

[37]林霖. 多组分压缩空气泡沫特性表征及灭火有效性实验研究 [D]. 合肥: 中国科学技术大学, 2007.

[38]李慧清. 压缩空气泡沫系统（CAFS）泡沫性能的试验研究 [D]. 北京: 北京林业大学, 2000.

[39]初迎霞. CAFS中流动参数与泡沫形态关系的试验研究 [D]. 北京: 北京林业大学, 2005.

[40]何勇, 安警彦, 顾嘉涛, 等. 一种压缩空气泡沫灭火系统中泡沫液混合发生装置 [P].中国专利: CN108635702A, 2018-10-12.

[41]张峰. 一种泡沫发生装置 [P]. 中国专利: CN108057349A, 2018-05-22.

[42]郎需庆, 牟小冬, 张卫华. 一种大流量压缩空气泡沫混合装置 [P]. 中国专利: CN105126277A, 2015-12-09.

[43]Xue L. Water-saving and high efficiency firefighting equipment and application technology research [R]. Shanghai Fire Research Institute, 2008.

[44]冯冬云. 固定式压缩空气泡沫系统的研制与实验研究 [D]. 廊坊: 中国人民武装警察部队学院, 2013.

[45]Feng D Y. Analysis on influencing factors of the gas-liquid mixing effect of compressed air foam systems [J]. Procedia Engineering, 2013, 52: 105-111.

[46]康万利, 黄子桐, 杨红斌, 等. 基于多重光散射法研究CO2泡沫稳定性 [J]. 日用化学工业, 2019, 49(10): 627-632.

[47]王克亮, 杜姗. 稳泡剂对泡沫性能影响室内实验研究 [J]．内蒙古石油化工, 2008, 34 (22): 4-5．

[48]Stefan H, Dorte L, Enda C, et al. Evaluation of a steady-state test of foam stability [J]. Philosophical Magazine, 2011, 91(4): 537-556．

[49]陈贻建, 张志庆, 苑世领, 等. 电导率法研究煤油/水乳状液的稳定性 [J]. 山东大学学报(理学版), 2003, 38(4): 88-91．

[50]Osei-Bonsu K, Shokri N, Grassia P. Foam stability in the presence and absence of hydrocarbons: From bubble-to bulk-scale [J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015, 481: 514-526.

[51]刘德生, 陈小榆. 温度对泡沫稳定性的影响研究 [J]. 中国海洋平台，2006, 21(4): 19-22．

[52]陈楠, 王治红, 刘友权, 等. 温度压力下起泡剂的起泡性和泡沫稳定性研究 [J]. 石油与天然气化工, 2017, 46(5): 65-68.

[53]Yang W P, Wang T F, Fan Z X, et al. Foams stabilized by in situ-modified nanoparticles and anionic surfactants for enhanced oil recovery [J]. Energy & Fuels, 2017, 31(5): 4721-4730.

[54]伍毅, 戴经天, 贾井运, 等. 发泡倍数对水成膜泡沫灭火剂性能的影响 [J]. 消防科学与技术, 2017, 36(8): 1113-1115.

[55]罗慧中, 邓艳丽, 何同继, 等. 油罐火灾高、低倍数泡沫灭火特性比较研究 [J]. 消防科学与技术, 2017, 36(3): 339-341.

[56]娄岩岩, 方正, 廖宇凡, 等. 综合管廊内影响高倍数泡沫破灭因素的研究 [J]. 科技创新导报, 2017, 14(22): 26-27.

[57]陈现涛, 贾井运, 贺元骅, 等. 气液比对水成膜泡沫灭火剂性能影响的实验研究 [J]. 消防科学与技术, 2016, 35(3): 404-407.

[58]Argillier J F, Saintpere S, Herzhaft B, et al. Stability and flowing properties of aqueous foams for underbalanced drilling [C]. SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 1998.

[59]Abhishek G, Ramadan A, Subhash S, et al. Stability of foams in pipe and annulus [J]. Journal of Petroleum Science and Engineering, 2019 (180): 594-604.

[60]Koehler S A, Hilgenfeldt S, Stone H A. A generalized view of foam drainage: Experiment and Theory [J]. Langmuir, 2000, 16(15): 6327-6341.

[61]Weaire D, Hutzler S, Verbist G, et al. A review of foam drainage [M]. Advances in Chemical Physics, 2007.

[62]彭磊, 何文敏, 畅亚文, 等. 压缩空气泡沫系统及其产泡特性研究 [J]. 隧道建设(中英文), 2019, 39(11): 1815-1822.

[63]马琳, 祁江涛, 刘竹青. 气泡尺寸分布的图像显微测量方法研究 [C]. 第七届全国信号和智能信息处理与应用学术会议会刊, 2013.

[64]陈方圆, 李平平, 李向阳, 等. 侵入式光纤照相法测量气泡尺寸分布 [J]. 过程工程学报, 2016, 16(3): 361-366.

[65]汤华鹏, 温济铭, 谷海峰. 基于高速摄影测量气泡体积的图像处理技术研究 [J]. 应用科技, 2019, 46(2): 108-115.

[66]Lichti M, Bart H J. Bubble size distributions with a shadowgraphic optical probe [J]. Flow Measurement and Instrumentation, 2018(60): 164-170.

[67]钟声远. 特长铁路隧道救援站内压缩空气泡沫灭火性能研究 [D]. 天津: 天津商业大学, 2017.

[68]贾乐强. 高高原环境下水成膜泡沫灭火性能研究 [D]. 成都: 中国民用航空飞行学院, 2016.

[69]Kim A.K.. Advances in fire suppression systems [J]. Construction Technology Updates, 2011, 75: 1-6.

[70]Kim A.K., Crampton G P. Application of a newly-developed compressed-air-foam fire suppression system [C]. Proceedings of Interflam, 2001: 1219-1224.

[71]Crampton G P. The determination of a safety factor for the application density of compressed-air foam on flammable liquid fires [M]．Institute for Research in Construction, 2004．

[72]Chen T, Fu X C, Bao Z M, et al. Experimental study on the extinguishing efficiency of compressed air foam sprinkler system on oil pool fire [J]. Procedia Engineering, 2018, 211: 94-103.

[73]林霖, 张永丰, 张字, 等. 压缩空气泡沫熄灭油池火的有效性 [J]. 燃烧科学与技术, 2008(2): 176-180．

[74]Wang K, Fang J, Shah H R, et al. A theoretical and experimental study of extinguishing compressed air foam on an n-heptane storage tank fire with variable fuel thickness [J]. Process Safety and Environmental Protection, 2020, 138: 117-129.

[75]GB15308-2006. 泡沫灭火剂 [S]. 北京: 中国标准出版社, 2006.

[76]GB50151-2010. 泡沫灭火系统设计规范 [S]. 北京: 中国计划出版社, 2010.

[77]Wang J, Liu H Q, Ning Z F, et al. Experimental research and quantitative characterization of nitrogen foam blocking characteristics [J]. Energy & Fuels, 2012, 26(8): 5152-5163.

[78]郭建生. 泡沫枪口径及流量对泡沫灭火剂发泡性能影响研究 [D]. 中国民用航空飞行学院, 2019.

[79]吕明明, 王树众. 二氧化碳泡沫稳定性及聚合物对其泡沫性能的影响 [J]. 化工学报, 2014, 65(06): 2219-2224.