Insights into the Nonlinear Evolution of Flame Fronts through Experiments and Models - Basile Radisson (MOVE, LIPhy)

Due to the exothermicity of combustion reaction, premixed flames are intrinsically unstable. Consequently, cellular patterns are formed on the flame front resulting in rich and complex dynamics. Combustion usually involves several hundreds of elementary chemical reactions occurring in a 10$mu$m reactive layer that propagates in combustion chambers at the meter scale. This large scale separation renders a detailed description computationally intractable. Instead, asymptotic analysis can greatly simplify this problem.

In this seminar, I will present some laboratory experiments that allow for a precise analysis of the dynamics resulting from flame front propagation. I will then compare these experimental observations to minimal asymptotic models that offer much insight into this complex front propagation and allow for an astonishing reduction of the computational cost needed to emulate these dynamics. I will conclude by drawing the limitations of these asymptotic models and emphasize on what remains to be done in order to use them in practical applications.

[1] Radisson B., Denet B., & Almarcha C. (2020). Nonlinear dynamics of premixed flames: from deterministic stages to stochastic influence. Journal of Fluid Mechanics, 903, A17.

[2] Radisson B., Denet B., & Almarcha C. (2021). Nonlinear dynamics of flame fronts with large-scale stabilizing effects. Physical Review E, 103(6), 063104.

[3] Radisson B., Piketty-Moine J., & Almarcha C. (2019). Coupling of vibro-acoustic waves with premixed flame. Physical Review Fluids, 4(12), 121201.

[4] Radisson B., Denet B., & Almarcha C. (2022). Forcing of a flame by a periodic flow in a Hele-Shaw burner. Physical Review Fluids, 7(5), 053201.

Contact: Emmanuel Siéfert