Laminar flame speed

Laminar flame speed is a property of a combustible mixture. It is the speed at which an un-stretched flame will propagate through a quiescent mixture of unburned reactants. Laminar flame speed is given the symbol s_L. According to the thermal flame theory of Mallard and Le Chatelier, the un-stretched laminar flame speed is dependent on only three properties of a chemical mixture: the thermal diffusivity of the mixture, the reaction rate of the mixture and the temperature through the flame zone:

${\displaystyle s_{\mathrm {L} }^{\circ }={\sqrt {\alpha {\dot {\omega }}\left({\dfrac {T_{\mathrm {b} }-T_{\mathrm {i} }}{T_{\mathrm {i} }-T_{\mathrm {u} }}}\right)}}}$

${\displaystyle \alpha }$ is thermal diffusivity,

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