Enhancement of the Traveling Front Speeds in Reaction-diiusion Equations with Advection
نویسنده
چکیده
We establish rigorous lower bounds on the speed of traveling fronts and on the bulk burning rate in reaction-diiusion equation with passive advection. The non-linearity is assumed to be of either KPP or ignition type. We consider two main classes of ows. Percolating ows, which are characterized by the presence of long tubes of streamlines mixing hot and cold material, lead to strong speed-up of burning which is linear in the amplitude of the ow, U. On the other hand the cellular ows, which have closed streamlines, are shown to produce weaker increase in reaction. For such ows we get a lower bound which grows as U 1=5 for a large amplitude of the ow.
منابع مشابه
Enhancement of the Traveling Front Speeds in Reaction-Diffusion Equations with Advection
We establish rigorous lower bounds on the speed of traveling fronts and on the bulk burning rate in reaction-diffusion equation with passive advection. The non-linearity is assumed to be of either KPP or ignition type. We consider two main classes of flows. Percolating flows, which are characterized by the presence of long tubes of streamlines mixing hot and cold material, lead to strong speed-...
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