Influence of ignition energy and initial ambient humidity on physical hazard of flammable gases

• Project/Area Number: 15K01235
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social systems engineering/Safety system
• Research Institution: Tokyo University of Science, Suwa
• Principal Investigator: IMAMURA TOMOHIKO 諏訪東京理科大学, 工学部, 准教授 (50450664)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2016: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2015: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
• Keywords: 気相燃焼 / 可燃性ガス / 着火エネルギー / 環境湿度 / フィジカルハザード

Outline of Final Research Achievements

In this research, the influence of environment factors on the flammability and combustion strength has been clarified experimentally to contribute to the physical risk management in use of the flammable gases. Especially, the hypothesis for the influence of initial environment humidity on the LPG combustion has been developed by a series of experiment. It is that the flammability and combustion strength are controlled by the balance of the following three factors; (1) reaction promotion effect that the unreacted fuel reacts to the O radical and/or OH radical which are decomposed from the moisture, (2) reaction suppressing effect by cooling due to the latent heat and sensible heat of moisture, and (3) reaction suppressing effect due to the oxygen insufficient which is caused by adding the moisture. The validation of this hypothesis was guaranteed by the chemical equilibrium analysis. These results were reported as two papers, and the one of them was awarded the "Best Paper Award".

Research Products

• [Journal Article] Influence of Initial Humidity on the Flame Propagation Rate of LPG/Air and LPG/O2/N2 Mixtures (2018)
  • Author(s): Imamura, T., Ohtsuki, M., Kumata, S., Furuya, Y., Ohno, R., Tanaka, A., Kawaguchi, A.
  • Journal Title: Proceedings of 11st Asia-Oceania Symposium on Fire Science and Technology Volume: 印刷中
  • Peer Reviewed
• [Journal Article] Influence of Moisture on Flame Propagation Rate of LPG/Air and LPG/O2/N2 Mixture (2017)
  • Author(s): Imamura, T., Ohno, R., Tanaka, A., Kawaguchi, A., Ohtsuki, M., Kumata, S., Furuya, Y.
  • Journal Title: Proceedings of Asia Pacific Symposium on Safety 2017 Volume: -
  • Peer Reviewed
• [Presentation] Influence of Initial Humidity on the Flame Propagation Rate of LPG/Air and LPG/O2/N2 Mixtures (2018)
  • Author(s): Imamura, T., Ohtsuki, M., Kumata, S., Furuya, Y., Ohno, R., Tanaka, A., Kawaguchi, A.
  • Organizer: 11st Asia-Oceania Symposium on Fire Science and Technology
  • Int'l Joint Research
• [Presentation] Influence of Moisture on Flame Propagation Rate of LPG/Air and LPG/O2/N2 Mixture (2017)
  • Author(s): Imamura, T., Ohno, R., Tanaka, A., Kawaguchi, A., Ohtsuki, M., Kumata, S., Furuya, Y.
  • Organizer: Proceedings of Asia Pacific Symposium on Safety 2017
  • Int'l Joint Research
• [Presentation] 可燃性ガスの燃焼威力に及ぼす環境因子の影響－環境湿度の効果－ (2015)
  • Author(s): 六川京也，平野良周，滝澤優，今村友彦
  • Organizer: 第48回安全工学研究発表会
  • Place of Presentation: 朱鷺メッセ（新潟コンベンションセンター）
  • Year and Date: 2015-12-04