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Related papers: Flame Enhancement and Quenching in Fluid Flows

200 papers

We investigated a nonlinear advection-diffusion-reaction equation for a passive scalar field. The purpose is to understand how the compressibility can affect the front dynamics and the bulk burning rate. We study two classes of flows:…

Biological Physics · Physics 2013-07-01 Federico Bianco , Sergio Chibbaro , Davide Vergni , Angelo Vulpiani

We consider a simple model describing premixed combustion in the presence of fluid flow: reaction diffusion equation with passive advection and ignition type nonlinearity. Strong advection can suppress flames - a process we call quenching.…

Analysis of PDEs · Mathematics 2007-05-23 Alexander Kiselev , Andrej Zlatos

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 consider a simple scalar reaction-advection-diffusion equation with ignition-type nonlinearity and discuss the following question: What kinds of velocity profiles are capable of quenching any given flame, provided the velocity's…

Chaotic Dynamics · Physics 2007-05-23 Peter Constantin , Alexander Kiselev , Leonid Ryzhik

We consider a passive scalar that is advected by a prescribed mean zero divergence-free velocity field, diffuses, and reacts according to a KPP-type nonlinear reaction. We introduce a quantity, the bulk burning rate, that makes both…

Analysis of PDEs · Mathematics 2009-10-31 Peter Constantin , Alexander Kiselev , Adam Oberman , Leonid Ryzhik

We consider a reaction-diffusion equation in a cellular flow. We prove that in the strong flow regime there are two possible scenario for the initial data that is compactly supported and the size of the support is large enough. If the flow…

Analysis of PDEs · Mathematics 2007-05-23 A. Fannjiang , A. Kiselev , L. Ryzhik

We consider a system of reaction-diffusion equations with passive advection term and Lewis number not equal to one. Such systems are used to describe chemical reactions in a flow in a situation where temperature and material diffusivities…

Chaotic Dynamics · Physics 2009-10-31 Alexander Kiselev , Leonid Ryzhik

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 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

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

In this paper, we consider an aggregation equation with fractional diffusion and large shear flow, which arise from modelling chemotaxis in bacteria. Without the advection, the solution of aggregation equation may blow up in finite time.…

Analysis of PDEs · Mathematics 2024-04-25 Niu Binqian , Binbin Shi , Weike Wang

Shear flows are naturally expected to occur in astrophysical environments and potential sites of continuous non-thermal Fermi-type particle acceleration. Here we investigate the efficiency of expanding relativistic outflows to facilitate…

High Energy Astrophysical Phenomena · Physics 2016-12-14 F. M. Rieger , P. Duffy

We prove the existence and uniqueness, up to a shift in time, of curved traveling fronts for a reaction-advection-diffusion equation with a combustion-type nonlinearity. The advection is through a shear flow $q$. This analyzes, for…

Analysis of PDEs · Mathematics 2018-12-05 Mohammad El Smaily

Influences of reaction zone thickening and local extinctions on the burning rate of extremely turbulent hydrogen-enriched methane-air flames are investigated using simultaneous planar laser-induced fluorescence of formaldehyde molecule and…

Fluid Dynamics · Physics 2020-12-01 Sajjad Mohammadnejad , Qiang An , Patrizio Vena , Sean Yun , Sina Kheirkhah

G-equations are well-known front propagation models in turbulent combustion and describe the front motion law in the form of local normal velocity equal to a constant (laminar speed) plus the normal projection of fluid velocity. In level…

Analysis of PDEs · Mathematics 2015-05-19 Yu-Yu Liu , Jack Xin , Yifeng Yu

Three-dimensional laminar flow structures with mixing, chemical reaction, normal strain, and shear strain qualitatively representative of turbulent combustion at the small scales are analyzed. A mixing layer is subjected to counterflow in…

Fluid Dynamics · Physics 2020-12-16 William A. Sirignano

We study a reaction-diffusion equation in the cylinder $\Omega = \mathbb{R}\times\mathbb{T}^m$, with combustion-type reaction term without ignition temperature cutoff, and in the presence of a periodic flow. We show that if the reaction…

Analysis of PDEs · Mathematics 2009-11-10 Andrej Zlatos

In this paper we investigate the acceleration of the expansion of premixed spherical flames and evolution of the cellular patterns on their surfaces. An asymptotic model is used for the simulations and a spectral numerical algorithm is…

Fluid Dynamics · Physics 2017-02-01 V. Karlin , G. Sivashinsky

We study the evolution of a reactive field advected by a one-dimensional compressible velocity field and subject to an ignition-type nonlinearity. In the limit of small molecular diffusivity the problem can be described by a spatially…

Statistical Mechanics · Physics 2009-11-13 S. Berti , D. Vergni , A. Vulpiani

This study investigates the linear stability of a laminar premixed flame, anchored on a square cylinder and confined inside a channel. Many modern linear analysis concepts have been developed and validated around non-reacting bluff-body…

Fluid Dynamics · Physics 2022-11-11 Chuhan Wang , Lutz Lesshafft , Kilian Oberleithner
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