The Effects of unburned-gas temperature and pressure on the unstable behavior of cellular-flame fronts generated by intrinsic instability in hydrogen-air lean premixed flames under adiabatic and non-adiabatic conditions; Numerical simulation based on the detailed chemical reaction model

Thwe Thwe, A.  ; Kadowaki, Satoshi; Nagaishi, Ryuji 

In this study, we performed numerical calculations of unsteady reaction flow considering detailed chemical reactions, investigated the unstable behavior of hydrogen-air dilute premixed flame due to intrinsic instability, and clarified the effects of unburned gas temperature and pressure. I made it. The unstable behavior of the flame in a wide space was simulated, and the burning rate of the cellular flame was obtained. Then, the effects of heat loss and flame scale on flame unstable behavior were investigated. The burning velocity of a planar flame increases as the unburned-gas temperature increases and it decreases as the unburned-gas pressure and heat loss increase. The normalized burning velocity increases when the pressure increases and heat loss becomes large, and it decreases when the temperature increases. This is because the high unburned-gas pressure and heat loss promote the unstable behavior and instability of flame.