Study on Inert Gas-Form Extinction Method applied for Three-dimensional Arranged Fire

惰性气体形式灭火法应用于三维排列火灾的研究

• 批准号: 15310109
• 负责人: ITO Akihiko
• 金额: $ 6.53万
• 依托单位: Hirosaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15310109/
• 关键词: Fire; Extinguishments; Three dimensional arranged fire; Water form; Inert gas; Extinction time; Extinction concentration; 水性気泡

To reveal the fire characteristics subsisting multiple fire sources and fire extinguishing by inert gas-form, experiments were conducted for two small pool fires arranged in three dimensions. Two different kinds of fuels, n-heptane (luminous flame) and methanol (non-luminous flame) were employed for test fuels. As a result, mass burning rates for both of pans are lager than that of a single pool fire, especially the burning rate for upper pan is remarkable increases compared with that for lower pan. The external radiation heat and induced air flow by multiple flames contributes to increase of the burning rate for multiple pool fires. To clarify the effects of external radiation and induced flow on burning rate for multiple fire sources, the model calculations considered the effects of radiative heat fluxes and change of flow fields. When the fires are separated, the increases of burning rate depend on the radiative heat flux emitted from the other fire. When the fire sources are arranged in three dimensions, we found that not only the effect of the external radiation but the effect of the flow field is important. When the pan diameter is larger, the effect of radiative heat flux is larger and the influence of flow fields is relatively small. From the characteristic of the three-dimensional fire obtained by this study, supplying a strong and high fluidity form to the upper fire efficiently is required. To make a strong and high fluidity form, the diameter of a form was changed and the fire-extinguishing experiment was conducted. By setting the diameter of a form to about 1mm, the fluidity and the intensity of a form were able to increase, and a three-dimensional fire was able to effectively extinguish.

为了揭示多个火源存在的火灾特性和惰性气体灭火方式，对两个三维布置的小池火进行了实验研究。两种不同的燃料，正庚烷(发光火焰)和甲醇(非发光火焰)被用作试验燃料。结果表明，两种锅具的质量燃烧速率均大于单一池火，尤其是上部锅具的燃速明显高于下部锅具。外部辐射热量和多个火焰诱导的气流有助于提高多池火灾的燃烧速度。为了阐明外部辐射和诱导流动对多个火源燃烧速率的影响，模型计算考虑了辐射热流和流场变化的影响。当两个火分开时，燃烧速率的增加取决于另一个火发出的辐射热流。当火源布置在三维空间时，我们发现不仅外部辐射的影响很重要，而且流场的影响也很重要。当锅体直径较大时，辐射热流的影响较大，而流场的影响较小。从本研究得到的三维火灾的特点来看，需要有效地为上部火灾提供一种强而高的流动形式。为了制作出高流动性的模子，改变模子的直径，进行了灭火实验。通过将模板直径设置为1 mm左右，能够增加模板的流动性和强度，并能够有效扑灭三维火灾。

项目成果

Flame Spread and Extinction over Thermally Thick PMMA in Low Oxygen Concentration Flow

低氧浓度流中热厚 PMMA 上的火焰传播和熄灭

• 发表时间: 2005
• 期刊: Fire Safety Science - Proceedings of the Eighth International Symposium 8
• 作者: Y.KUDO;M.ITAKURA;Y.FUJITA;A.ITO
• 通讯作者: A.ITO

減酸素気流中のPMMAの燃え広がりと消炎に与える酸素濃度と流速の影響

氧气浓度和流量对PMMA在减氧气流中火焰蔓延和熄灭的影响

• 发表时间: 2005
• 期刊: 平成17年度日本火災学会研究発表会概要集
• 作者: 藤田裕也;板倉瑞恵;工藤祐嗣;伊藤昭彦
• 通讯作者: 伊藤昭彦

同軸気流中のプール火災の保炎機構

同轴气流池火的火焰保持机制

• 发表时间: 2005
• 期刊: 第43回燃焼シンポジウム講演論文集
• 作者: 泉 潤;福田真弓;工藤祐嗣;伊藤昭彦
• 通讯作者: 伊藤昭彦

Scaling and instability analyses on flame spread over liquids

• DOI: 10.1016/j.proci.2004.08.246
• 发表时间: 2005
• 作者: Kozue Takahashi;A. Ito;Y. Kudo;T. Konishi;Kozo Saito

Simultaneous Measurement of Temperature and Chemical Species Concentrations with Holographic Interferometer and Infrared Absorption

利用全息干涉仪和红外吸收同时测量温度和化学物质浓度

• 发表时间: 2006
• 期刊: Applied Optics 46・22
• 作者: T.Konishi;A.Ito;Y.Kudo;A.Narumi;K.Saito;J.Baker;P.M..Struk
• 通讯作者: P.M..Struk