Accueil  >  Séminaires  >  Autocatalytic reaction fronts in disorder media
Autocatalytic reaction fronts in disorder media
Par Laurent Talon
Le 14 Mars 2018 à 11h00 - Salle de séminaires 5ème étage, Tour 32-33

Résumé

Autocatalytic reaction fronts between two reacting species, propagate as solitary waves. The coupling between autocatalytic reaction front and forced hydrodynamic flow may lead to stationary fronts whose velocity and shape depend on the underlying flow field. We focus on the issue of the chemo-hydrodynamic coupling between forced advection opposed to these self-sustained chemical waves. which can lead to static stationary fronts, i.e Frozen Fronts.

For the flow inside a porous medium, we report on numerical studies of the dynamics of the front for the same IAA autocatalytic reaction front. The front propagation is controlled by the adverse flow resulting in fronts propagating either upstream or downstream, or remaining "frozen" (FF). Focusing on front shape, we have recently identified three different universality classes associated with this system by following the front dynamic experimentally and numerically. Here, using numerical simulation, in the vicinity of the depinning transition between FF and upstream fronts, we find power-law distributions of avalanche sizes, duration and lateral extensions. The related exponents are compared with the so-called qKPZs theory that describes the front dynamic.