Nonlinear Analysis of Outward Propagating Hydrodynamically Unstable Flame at Large Gas Expansion Ratio

Abstract

In the context of the large thermal-expansion approximation, we derive an equation describing outward propagating flame under conditions of Darrieus–Landau instability. We show that the second-order theory leads to system of two evolution equations for the flame front perturbations and for the potential of the unburned mixture flow. In the limiting case of long evolution, the system of equations can be reduced to one equation similar to the Sivashinsky equation.