This work presents the experimental and numerical investigation of premixed flame propagation in a constant volume rectangular channel that serves as a combustion chamber. Flames inside closed vessels undergo distinct transformations in their physical structure; ignition event is followed by an accelerating convex shaped flame-front, then a deceleration of the flame is followed by the formation of a concave "tulip" shaped flame-front. Eventually, the flame is dissipated either because of quenching by the cold wall or by collision with a flame that has been ignited on the opposite end of the confined channel. phenomena observed include both the formation of concave flame-fronts and oscillating convex-concave flame-fronts. The structure and speed of flame propagation is characterized for changes in equivalence ratio, initial pressure, timing and placement of the ignition sources. Numerical and analytical calculations of the combustion phenomena are performed to understand the effect of the pressure waves and various instabilities causing the changes to the flame structure. The transient numerical results are validated using experimental results.
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