Reaction Front & Combustion

Fisher-KPP / Zeldovich combustion front: a reaction-diffusion equation ∂u/∂t = D∇²u + f(u) with Arrhenius kinetics. The front propagates at the minimum wave speed c* = 2√(Df'(0)). Ignition temperature controls flame initiation.

Combustion

Diffusivity D 1.00 Reaction rate k 1.00 Activation energy E_a 2.00 Ignition threshold θ 0.30 Model

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c* = 2√(Dk) (KPP speed)
Front width ∝ √(D/k)