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arXiv · 1410.1097

Experimental evidence for three universality classes for reaction fronts in disordered flows

Séverine Atis·Awadhesh Kumar Dubey·Dominique Salin·Laurent Talon·Pierre Le Doussal·Kay Jörg Wiese
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Abstract

Self-sustained reaction fronts in a disordered medium subject to an external flow display self-affine roughening, pinning and depinning transitions. We measure spatial and temporal fluctuations of the front in $1+1$ dimensions, controlled by a single parameter, the mean flow velocity. Three distinct universality classes are observed, consistent with the Kardar-Parisi-Zhang (KPZ) class for fast advancing or receding fronts, the quenched KPZ class (positive-qKPZ) when the mean flow approximately cancels the reaction rate, and the negative-qKPZ class for slowly receding fronts. Both quenched KPZ classes exhibit distinct depinning transitions, in agreement with the theory.

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Séverine Atis, Awadhesh Kumar Dubey, Dominique Salin, Laurent Talon, Pierre Le Doussal, Kay Jörg Wiese. 2015-03-27. Experimental evidence for three universality classes for reaction fronts in disordered flows. https://doi.org/10.1103/physrevlett.114.234502

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