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Related papers: KPP Pulsating Front Speed-up by Flows

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We consider reaction-diffusion equations with combustion-type non-linearities in two dimensions and study speed-up of their pulsating fronts by general periodic incompressible flows with a cellular structure. We show that the occurence of…

Analysis of PDEs · Mathematics 2009-11-13 Andrej Zlatos

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 $D(A)/A^2$ as $A\to\infty$, where $c^*(A)$ is the…

Analysis of PDEs · Mathematics 2007-07-05 Andrej Zlatos

We study flow-induced enhancement of the speed of pulsating traveling fronts for reaction-diffusion equations, and quenching of reaction by fluid flows. We prove, for periodic flows in two dimensions and any combustion-type reaction, that…

Analysis of PDEs · Mathematics 2009-05-27 Andrej Zlatos

We prove the existence of reaction-diffusion traveling fronts in mean zero space-time periodic shear flows for nonnegative reactions including the classical KPP (Kolmogorov-Petrovsky-Piskunov) nonlinearity. For the KPP nonlinearity, the…

Analysis of PDEs · Mathematics 2007-05-23 James Nolen , Jack Xin

We study analytically and numerically a model describing front propagation of a KPP reaction in a fluid flow. The model consists of coupled one-dimensional reaction-diffusion equations with different drift coefficients. The main rigorous…

Analysis of PDEs · Mathematics 2007-05-23 Lam Raga A. Markely , David Andrzejewski , Erick Butzlaff , Alexander Kiselev

We study, in dimensions $N\geq 3$, the family of first integrals of an incompressible flow: these are $H^{1}_{loc}$ functions whose level surfaces are tangent to the streamlines of the advective incompressible field. One main motivation for…

Analysis of PDEs · Mathematics 2014-05-21 Mohammad El Smaily , Stéphane Kirsch

We consider in this paper a reaction-diffusion system in presence of a flow and under a KPP hypothesis. While the case of a single-equation has been extensively studied since the pioneering Kolmogorov-Petrovski-Piskunov paper, the study of…

Analysis of PDEs · Mathematics 2015-05-18 Thomas Giletti

We study a Fisher-KPP equation with spatially periodic diffusion and reaction terms. We identify a class of periodic media for which the equation admits an explicit, closed-form solution. Through a nonlinear change of variables, the problem…

Analysis of PDEs · Mathematics 2025-12-09 Lionel Roques

We investigate the influence of fluid flows on the propagation of chemical fronts arising in FKPP type models. We develop an asymptotic theory for the front speed in a cellular flow in the limit of small molecular diffusivity and fast…

Fluid Dynamics · Physics 2014-07-16 Alexandra Tzella , Jacques Vanneste

In this paper we are interested in propagation phenomena for nonlocal reaction-diffusion equations of the type: $\delta_tu = J \times u - u + f (x, u) t \in R^+, x \in R^N$, where J is a probability density and f is a KPP nonlinearity…

Analysis of PDEs · Mathematics 2013-02-06 Jerome Coville , Juan Davila , Salome Martinez

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…

Chaotic Dynamics · Physics 2009-11-07 M. Abel , M. Cencini , D. Vergni , A. Vulpiani

In this paper, we prove via counterexamples that adding an advection term of the form Shear flow (whose streamlines are parallel to the direction of propagation) to a reaction-diffusion equation will be an enough heterogeneity to spoil the…

Analysis of PDEs · Mathematics 2013-07-30 Mohammad El Smaily

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…

Analysis of PDEs · Mathematics 2015-06-26 Alexander Kiselev , Leonid Ryzhik

We study the velocity of travelling waves of a reaction-diffusion system coupling a standard reaction-diffusion equation in a strip with a one-dimensional diffusion equation on a line. We show that it grows like the square root of the…

Analysis of PDEs · Mathematics 2015-07-02 Laurent Dietrich

This paper is concerned with the analysis of speed-up of reaction-diffusion-advection traveling fronts in infinite cylinders with periodic boundary conditions. The advection is a shear flow with a large amplitude and the reaction is…

Analysis of PDEs · Mathematics 2011-12-15 Francois Hamel , Andrej Zlatos

The aim of this paper is to study the generalized Fisher-KPP equation with nonlocal diffusion. In specific we prove the existence of a critical speed so that traveling front type solutions exist up to this critical speed and non-existence…

Analysis of PDEs · Mathematics 2021-04-28 José Fuentealba , Alexander Quaas

This paper is concerned with some nonlinear propagation phenomena for reaction-advection-diffusion equations with Kolmogrov-Petrovsky-Piskunov (KPP) type nonlinearities in general periodic domains or in infinite cylinders with oscillating…

Analysis of PDEs · Mathematics 2010-11-23 Mohammad El Smaily

We consider here a model of accelerating fronts, introduced in [2], consisting of one equation with nonlocal diffusion on a line, coupled via the boundary condition with a reaction-diffusion equation of the Fisher-KPP type in the upper…

Analysis of PDEs · Mathematics 2019-11-11 Anne-Charline Chalmin , Jean-Michel Roquejoffre

This paper is devoted to the study of the asymptotic behaviors of the minimal speed of propagation of pulsating traveling fronts solving the Fisher-KPP reaction-advection-diffusion equation within either a large drift, a mixture of large…

Analysis of PDEs · Mathematics 2011-04-15 Mohammad El Smaily , Stephane Kirsch

We consider the effect of a shear flow which has, without loss of generality, a zero mean flow rate, on a Kolmogorov--Petrovskii--Piscounov (KPP) type model in the presence of a discontinuous cut-off at concentration $u = u_c$. Its…

Analysis of PDEs · Mathematics 2024-06-25 D. J. Needham , A. Tzella
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