English
Related papers

Related papers: Premixed flame propagation in vertical tubes

200 papers

The paper is studying the dynamics of twisted vortex bundles, which were detected in experimental investigations of superfluid turbulence in superfluid 3He-B. The analysis shows that a linear torsion oscillation of a vortex bundle is a…

Other Condensed Matter · Physics 2015-05-28 E. B. Sonin

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

A fluid dynamics video was created using data from a Direct Numerical Simulation of a premixed n-heptane flame at high Karlovitz number. The magnitude of vorticity and progress variable(a monotonically increasing variable through the flame)…

Fluid Dynamics · Physics 2013-10-15 Brock Bobbitt , Bruno Savard , Guillaume Blanquart

Large-eddy simulations (LES) of a planar turbulent lean hydrogen-air jet flame at Re = 11000 are performed using a tabulated flamelet model based on mixture-averaged diffusion that incorporates detailed transport, including differential and…

The scaling of turbulent premixed flames is typically described by correlations derived for unity-Lewis-number fuels. However, their validity for hydrogen (H$_{2}$) remains uncertain due to the thermodiffusive effects associated with its…

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

This paper presents an experimental analysis of flame-induced enstrophy transport in premixed swirl combustion at Karlovitz numbers between 20-50. Such flames posses a large-scale pressure field that -- in addition to the pressure fields…

Fluid Dynamics · Physics 2020-09-02 Askar Kazbekov , Adam M. Steinberg

We establish a comparison between Rakib--Sivashinsky and Michelson-Sivashinsky quasilinear parabolic differential equations governing the weak thermal limit of upward flame front propagating in a channel. For the former equation, we give a…

Analysis of PDEs · Mathematics 2007-05-23 Leonardo F. Guidi , Domingos H. U. Marchetti

Flickering buoyant diffusion methane flames in weakly rotatory flows were computationally and theoretically investigated. The prominent computational finding is that the flicker frequency nonlinearly increases with the rotational intensity…

Fluid Dynamics · Physics 2023-12-06 Tao Yang , Peng Zhang

We consider the propagation of a flame front in a solid medium with a periodic structure. The model is governed by a free boundary system for the pair" temperature-front. "The front's normal velocity depends on the temperature via a…

Analysis of PDEs · Mathematics 2016-02-03 Nathaël Alibaud , Gawtum Namah

Propagation of turbulent premixed flames influenced by the intrinsic hydrodynamic flame instability (the Darrieus-Landau instability) is considered in a two-dimensional case using the model nonlinear equation proposed recently. The…

Mathematical Physics · Physics 2012-11-27 Maxim Zaytsev , Vitaliy Bychkov

Flame Propagation is used as a prototypical example of expanding fronts that wrinkle without limit in radial geometries but reach a simple shape in channel geometry. We show that the relevant scaling laws that govern the radial growth can…

Pattern Formation and Solitons · Physics 2011-08-19 Barak Galanti , Oleg Kupervasser , Zeev Olami , Itamar Procaccia

Lean turbulent premixed hydrogen/air flames have substantially increased flame speeds, commonly attributed to differential diffusion effects. In this work, the effect of turbulence on lean hydrogen combustion is studied through Direct…

Fluid Dynamics · Physics 2024-08-20 Matthew X. Yao , Guillaume Blanquart

Turbulence is of paramount importance in wildland fire propagation since it randomly transports the hot air mass that can pre-heat and then ignite the area ahead the fire. This contributes to give a random character to the firefront…

Atmospheric and Oceanic Physics · Physics 2014-08-27 Gianni Pagnini , Luca Massidda

The present work investigates the structure of fast supersonic turbulent flames typically observed as precursors to the onset of detonation. These high speed deflagrations are obtained after the interaction of a detonation wave with…

Turbulent premixed flames are important for power generation using gas turbines. Improvements in characterization and understanding of turbulent flames continue particularly for transient events like ignition and extinction. Pockets or…

Computer Vision and Pattern Recognition · Computer Science 2020-12-04 Rathziel Roncancio , Jupyoung Kim , Aly El Gamal , Jay P. Gore

A joint experimental and numerical investigation of turbulent flame front anchoring at externally heated walls is presented. The phenomenon is examined for lean hydrogen/air mixtures in a novel burner design, which comprises a cylindrical…

Fluid Dynamics · Physics 2020-03-25 S. Klukas , M. Sieber , M. Giglmaier , S. Schimek , C. O. Paschereit , N. A. Adams

Data from a three-dimensional Direct Numerical Simulation of a turbulent premixed Bunsen flame at a low global Lewis number are analyzed to address the effects of the curvature on the local flame front. For this purpose, the chemical…

We present a model for plasma heating produced by time-dependent, spatially localized reconnection within a flare current sheet separating skewed magnetic fields. The reconnection creates flux tubes of new connectivity which subsequently…

Solar and Stellar Astrophysics · Physics 2015-05-19 Silvina Guidoni , Dana Longcope

We propose a predictive model of the turbulent burning velocity over a wide range of conditions. The model consists of sub models of the stretch factor and the turbulent flame area. The stretch factor characterizes the flame response of…

Fluid Dynamics · Physics 2024-07-25 Zhen Lu , Yue Yang