Research on the sophistication of fire extinguishing equipment and fire extinguishing tactics focusing on the difference in gravitational environment

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04925
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 25020:Safety engineering-related
• Research Institution: Hachinohe Institute of Technology
• Principal Investigator: KUDO Yuji 八戸工業大学, 大学院工学研究科, 教授 (80333714)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ゴースティング火炎 / 区画火災 / ガス系消火設備 / 消防戦術 / 微小重力環境火災

Outline of Final Research Achievements

If a compartment fire occurs under low oxygen concentration conditions with high airtightness and poor ventilation conditions, a ghosting flame that randomly moves around in the compartment may occur. On the other hand, it has been reported that the flammable limit oxygen concentration decreases in a low gravity environment where the inflow rate of air into the flame is limited. An experiment was conducted to compare the two, and the formation of a flammable air-fuel mixture layer was confirmed immediately before the occurrence of the ghosting flame, and the temperature rise of the lower layer and the temperature decrease of the upper layer were confirmed. It was found that the effect of buoyancy is small in the flammable air-fuel mixture layer.

Free Research Field

火災安全工学

Academic Significance and Societal Importance of the Research Achievements

密閉度が高く換気条件が悪い低酸素濃度条件下で区画火災が生じた場合，区画内をランダムに動き回るゴースティング火炎が発生することがある．この可燃濃度範囲の低下により，ガス系消火設備が十分働かない可能性がある．本研究では，可燃性混合気層の形成により，ゴースティング火炎が低酸素濃度条件下で換気が供給されていれば発生することを明らかにし，低重力環境での燃え拡がりにおける低酸素側への燃焼範囲の拡大との類似性を明らかにすることで，効果的なガス系消火設備の設計や消防隊が安全に火災区画内に内部侵入するための指針策定に関わる基礎データを得ることができた．