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Front speed enhancement in cellular flows

M. Abel·M. Cencini·D. Vergni·A. Vulpiani
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Abstract

The problem of front propagation in a stirred medium is addressed in the case of cellular flows in three different regimes: slow reaction, fast reaction and geometrical optics limit. It is well known that a consequence of stirring is the enhancement of front speed with respect to the non-stirred case. By means of numerical simulations and theoretical arguments we describe the behavior of front speed as a function of the stirring intensity, $U$. For slow reaction, the front propagates with a speed proportional to $U^{1/4}$, conversely for fast reaction the front speed is proportional to $U^{3/4}$. In the geometrical optics limit, the front speed asymptotically behaves as $U/\ln U$.

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M. Abel, M. Cencini, D. Vergni, A. Vulpiani. 2001-10-08. Front speed enhancement in cellular flows. https://doi.org/10.1063/1.1457467

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