Speed of reaction-diffusion fronts in spatially heterogeneous media
نویسندگان
چکیده
منابع مشابه
Speed of reaction-diffusion fronts in spatially heterogeneous media.
The front speed problem for nonuniform reaction rate and diffusion coefficient is studied by using singular perturbation analysis, the geometric approach of Hamilton-Jacobi dynamics, and the local speed approach. Exact and perturbed expressions for the front speed are obtained in the limit of large times. For linear and fractal heterogeneities, the analytic results have been compared with numer...
متن کاملSpeed of traveling fronts in a sigmoidal reaction-diffusion system.
We study a sigmoidal version of the FitzHugh-Nagumo reaction-diffusion system based on an analytic description using piecewise linear approximations of the reaction kinetics. We completely describe the dynamics of wave fronts and discuss the properties of the speed equation. The speed diagrams show front bifurcations between branches with one, three, or five fronts that differ significantly fro...
متن کاملSpeed of Fronts of the Reaction-Diffusion Equation.
In a recent paper Goriely considers the one–dimensional scalar reaction– diffusion equation ut = uxx + f(u) with a polynomial reaction term f(u) and conjectures the existence of a relation between a global resonance of the hamiltonian system uxx+f(u) = 0 and the asymptotic speed of propagation of fronts of the reaction diffusion equation. Based on this conjecture an explicit expression for the ...
متن کاملMinimal speed of fronts of reaction-convection-diffusion equations.
We study the minimal speed of propagating fronts of convection-reaction-diffusion equations of the form u(t)+microphi(u)u(x)=u(xx)+f(u) for positive reaction terms with f(')(0)>0. The function phi(u) is continuous and vanishes at u=0. A variational principle for the minimal speed of the waves is constructed from which upper and lower bounds are obtained. This permits the a priori assessment of ...
متن کاملPattern formation in spatially heterogeneous Turing reaction–diffusion models
The Turing reaction–diffusion model [Phil. Trans. R. Soc. 237 (1952) 37–72] for self-organised spatial pattern formation has been the subject of a great deal of study for the case of spatially homogeneous parameters. The case of parameters which vary spatially has received less attention. Here, we show that a simple step function heterogeneity in a kinetic parameter can lead to spatial pattern ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review E
سال: 2003
ISSN: 1063-651X,1095-3787
DOI: 10.1103/physreve.68.041105