KPP Pulsating Front Speed-up by Flows
نویسندگان
چکیده
We obtain a criterion for pulsating front speed-up by general periodic incompressible flows in two dimensions and in the presence of KPP nonlinearities. We achieve this by showing that the ratio of the minimal front speed and the effective diffusivity of the flow is bounded away from zero and infinity by constants independent of the flow. We also study speed-up of reaction-diffusion fronts by various examples of flows in two and three dimensions.
منابع مشابه
Sharp Asymptotics for Kpp Pulsating Front Speed-up and Diffusion Enhancement by Flows
We study KPP pulsating front speed-up and effective diffusivity enhancement by general periodic incompressible flows. We prove the existence of and determine the limits c∗(A)/A and D(A)/A as A → ∞, where c∗(A) is the minimal front speed and D(A) the effective diffusivity.
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