Mathematics of unstable combustion: extinction and flame oscillation

Reference No. 2022a011
Type/Category Grant for General Research-Short-term Joint Research
Title of Research Project Mathematics of unstable combustion: extinction and flame oscillation
Principal Investigator Kazunori Kuwana(Department of Global Fire Science and Technology / Professor)
Research Period November 04, 2022. - November 04, 2022.
March 06, 2023. - March 06, 2023.
Keyword(s) of Research Fields Combustion engineering and science, asymptotic analysis, bifurcation theory, combustion instability, flame oscillation, extinction
Abstract for Research Report In FY2021, research entitled "Fire and Explosion Safety Measures Based on the Mathematics of Combustion and Extinction Mechanisms" was conducted. The project aimed to connect the mathematical theory of extinction limit to safety measures for fire and explosion phenomena, attempting to clarify various combustion modes of gas, solid, and dust. Combustion oscillation and flame instability are observed near extinction limits, further affecting the limit conditions.
Flame extinction and unstable combustion conditions are important design factors for setting the operating conditions of industrial combustors. Unexpected extinction or unstable combustion can lead to downstream runaway reactions or explosions in combustors. It is also known empirically that unstable combustion causes secondary effects such as increased production of toxic carbon monoxide. Furthermore, flame oscillation can cause combustion noise. Therefore, safe and stable combustor operation requires clarifying the conditions under which unstable combustion occurs.
The proposed project aims to establish a mathematical model that describes extinction and combustion instability, combining it with the reactor-design theory to provide knowledge used in reactor design. The results of this research can be used for quantitative risk assessment of industrial processes. Quantitative risk assessment of combustors is not widely conducted at present. Although some guidelines have been proposed, they are not based on the mathematics of unstable combustion. This study aims to provide information that will contribute to developing guidelines for quantitative risk assessment based on mathematics.
Organizing Committee Members (Workshop)
Participants (Short-term Joint Usage)
Kazunori Kuwana(Tokyo University of Science / Professor)
Yasuhide Fukumoto(Kyushu University / Professor)
Kaname Matsue(Kyushu University / Associate Professor)
Shigetoshi Yazaki(Meiji University / Professor)
Hirofumi Izuhara(University of Miyazaki / Associate Professor)
Shunsuke Kobayashi(Kyoto University / Assistant Professor)
Takayuki Tomizuka( AdvanceSoft Corporation / Vice Director)