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Related papers: On-Shell Description of Unsteady Flames

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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

An unconfined strongly swirled flow is investigated for different Reynolds numbers using particle image velocimetry (PIV) and Large Eddy Simulation (LES) with a Thickened Flame (TF) model. Both reacting and non-reacting flow results are…

Fluid Dynamics · Physics 2021-03-05 Ashoke De , Shengrong Zhu , Sumanta Acharya

A kinetic flux-splitting procedure used in conjunction with local thermodynamic equilibrium in a finite volume allows us to investigate numerically discrete-velocity gas flows. The procedure, outlined for a general discrete-velocity gas, is…

comp-gas · Physics 2008-02-03 Balu Nadiga Galcit

The dynamics (in light-cone time) of the tachyon on an unstable brane in the background of a dilaton linear along a null coordinate is a non-local reaction-diffusion type equation, which admits a travelling front solution. We analyze the…

High Energy Physics - Theory · Physics 2014-07-24 Debashis Ghoshal , Preeda Patcharamaneepakorn

Nonpremixed turbulent reacting flows are intrinsically difficult to model due to the strong coupling between turbulent motions and reaction. The large amount of heat released by a typical hydrocarbon flame leads to significant modifications…

Fluid Dynamics · Physics 2007-05-23 Daniel Livescu , Cyrus K. Madnia

Premixed-flame wrinkling is studied via a Michelson-Sivashinsky (MS) type of evolution equation retaining the Darrieus-Landau (DL) instability, a curvature effect and a geometric nonlinearity. Here it also keeps forcing by longitudinal…

Pattern Formation and Solitons · Physics 2019-09-17 Guy Joulin , Bruno Denet

Flame instabilities play a dominant role in accelerating the burning front to a large fraction of the speed of sound in a Type Ia supernova. We present a three-dimensional numerical simulation of a Rayleigh-Taylor unstable carbon flame,…

Astrophysics · Physics 2009-11-10 M. Zingale , S. E. Woosley , C. A. Rendleman , M. S. Day , J. B. Bell

Intrinsic instabilities of laminar premixed flames play an important role in the dynamics of hydrogen combustion and in the development of predictive models for reacting flows. However, determining their dispersion relations typically…

Fluid Dynamics · Physics 2026-03-31 Thomas Ludwig Kaiser , Peter Munch , Sandra May , Thorsten Zirwes

A high-pressure hydrogen micromix combustor has been investigated using direct numerical simulation with detailed chemistry to examine the flame structure and stabilisation mechanism. The configuration of the combustor was based on the…

This study introduces a novel experimental configuration using OH-PLIF imaging to directly determine the stretch factor ($I_0$) in laminar premixed hydrogen flames transitioning from a quasi-stable to a thermodiffusively unstable regime. A…

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

The three-dimensional diffusive-thermal stability of a two-dimensional flame propagating in a Poiseuille flow is examined. The study explores the effect of three non-dimensional parameters, namely the Lewis number $Le$, the Damk\"ohler…

Fluid Dynamics · Physics 2024-07-09 Aiden Kelly , Prabakaran Rajamanickam , Joel Daou , Julien R. Landel

In combustion theory, flames are usually described in terms of the dynamics of iso-surfaces of a specific scalar. The flame displacement speed is then introduced as a local variable quantifying the progression of these iso-surfaces relative…

Fluid Dynamics · Physics 2024-12-18 Hernan Olguin , Pascale Domingo , Luc Vervisch , Christian Hasse , Arne Scholtissek

For certain values of the wave speed parameter, evolution equations for the temperature of a region of fuel admit traveling wave solutions describing fire fronts. We consider such a system in the form of a nonlinear reaction-diffusion…

Pattern Formation and Solitons · Physics 2024-10-29 Olivia Chandrasekhar , Christopher K. R. T. Jones , Blake Barker , Rodman Linn

The current paper is a corrected version of our previous paper arXiv:adap-org/9608001. Similarly to previous version we investigate the problem of flame propagation. This problem is studied as an example of unstable fronts that wrinkle on…

Chaotic Dynamics · Physics 2013-04-23 Oleg Kupervasser , Zeev Olami

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

Solutions of the spray flamelet equations reported in the literature during the last decade have been limited to very specific situations presenting steady evaporation profiles only. In contrast, intrinsically unsteady interactions between…

Hydrogen combustion systems operated under fuel-lean conditions offer great potential for low emissions. However, these operating conditions are also susceptible to intrinsic thermodiffusive combustion instabilities. Even though technical…

Fluid Dynamics · Physics 2025-07-14 Max Schneider , Hendrik Nicolai , Vinzenz Schuh , Matthias Steinhausen , Christian Hasse

We consider a free interface problem which stems from a solid-gas model in combustion with pattern formation. We derive a third-order, fully nonlinear, self-consistent equation for the flame front. Asymptotic methods reveal that the…

Analysis of PDEs · Mathematics 2012-11-06 Claude-Michel Brauner , Lina Hu , Luca Lorenzi

The stabilization mechanisms of fully premixed NH3/H2/air flames anchored behind a bluff body are investigated using combined experiments and direct numerical simulations. Particular attention is given to the interplay between preferential…

Fluid Dynamics · Physics 2026-03-10 Lukas Gaipl , Wei Guan , Ganesh Guggilla , Alexey Kropman , Frank Beyrau , Dominique Thévenin