English
Related papers

Related papers: Flame-capturing technique. 1: Adaptation to gas ex…

200 papers

We first briefly recall the basic mechanisms controlling the hydrodynamic and thermo-diffusive stability of planar laminar premixed flames, and give the state of the theoretical analysis. We then describe some novel experiments to observe…

Classical Physics · Physics 2007-05-23 Geoffrey Searby

Fuel-flexible, low-carbon combustion systems need to accommodate methane/hydrogen mixtures with air and exhaust-gas dilution. To develop these, we require accurate and efficient correlations for laminar flame speed (LFS). In this work, we…

An unconfined strongly swirled flow is investigated to study the effect of hydrogen addition on upstream flame propagation in a methane-air premixed flame using Large Eddy Simulation (LES) with a Thickened Flame (TF) model. A…

Fluid Dynamics · Physics 2021-02-10 Ashoke De , Sumanta Acharya

Flamelet-based methods are extensively used in modeling turbulent hydrocarbon flames. However, these models have yet to be established for (lean) premixed hydrogen flames. While flamelet models exist for laminar thermo-diffusively unstable…

Models for wildfires must be stochastic if their ability to represent wildfires is to be objectively assessed. The need for models to be stochastic emerges naturally from the physics of the fire, and methods for assessing fit are…

Computational Physics · Physics 2009-11-03 Jeffrey Picka

First-principles Markov Chain Monte Carlo sampling is used to investigate uncertainty quantification and uncertainty propagation in parameters describing hydrogen kinetics. Specifically, we sample the posterior distribution of thirty-one…

Numerical Analysis · Mathematics 2018-03-12 John Bell , Marcus Day , Jonathan Goodman , Ray Grout , Matthias Morzfeld

In the present study, soot formation in the turbulent lifted diffusion flame, consisting of ethylene-air is numerically investigated using three different soot modeling approaches and is comprehensively reported. For turbulence-chemistry…

Fluid Dynamics · Physics 2021-03-03 Rohit Saini , Ashoke De

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

It was demonstrated recently in Bychkov et al., Phys. Rev. Lett. 101 (2008) 164501, that the physical mechanism of flame acceleration in channels with obstacles is qualitatively different from the classical Shelkin mechanism. The new…

Fluid Dynamics · Physics 2012-11-06 Damir Valiev , Vitaly Bychkov , V'yacheslav Akkerman , Chung K. Law , Lars-Erik Eriksson

In the distributed burning regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning depends on the turbulent Damkohler number…

High Energy Astrophysical Phenomena · Physics 2011-07-14 A J Aspden , J B Bell , S E Woosley

Preferential diffusion plays a critical role in the evolution of lean premixed hydrogen flames, influencing flame surface corrugation and overall flame behavior. Simulating such flames with tabulated chemistry (TC) methods remains…

Premixed flames propagating within small channels show complex combustion phenomena that differ from flame propagation at conventional scales. Available experimental and numerical studies have documented stationary/non-stationary and/or…

Fluid Dynamics · Physics 2016-08-02 Mohsen Ayoobi , Ingmar Schoegl

There are many wildfire behaviors of increasing relevance that are outside the forecast capabilities of even the most sophisticated operational fire spread and fire behavior model. The limitations of the operational models are due primarily…

Atmospheric and Oceanic Physics · Physics 2013-03-26 Adam K. Kochanski , Mary Ann Jenkins , Steven K. Krueger , Jan Mandel , Jonathan D. Beezley

This paper presents a flame-height correlation for laminar to transition-to-turbulent regime diffusion flames. Flame-height measurements are obtained by means of numerical and experimental studies in which three high definition cameras were…

This paper presents the development of a new continuous forest fire model implemented as a weighted local small-world network approach. This new approach was designed to simulate fire patterns in real, heterogeneous landscapes. The wildland…

Atmospheric and Oceanic Physics · Physics 2013-07-02 F. Aguayo , A. Fuentes , J. -P. Clerc , B. Porterie

The paper discusses the peculiarities of flame propagation in the ultra-lean hydrogen-air mixture. Numerical analysis of the problem shows the possibility of the stable self-sustained flame ball existence in unconfined space on sufficiently…

Fluid Dynamics · Physics 2017-11-21 I. S. Yakovenko , M. F. Ivanov , A. D. Kiverin , K. S. Melnikova

We introduce a phase-field model to describe the dynamics of a self-sustaining propagating combustion front within a medium of randomly distributed reactants. Numerical simulations of this model show that a flame front exists for reactant…

Condensed Matter · Physics 2009-10-22 N. Provatas , T. Ala-Nissila , Martin Grant , K. R. Elder , Luc Pich

Flames can be formed by burning methane (CH4). When oxygen is scarce, carbon particles nucleate into solid particles called soot. These particles emit photons, making the flame yellow. Later, methane is pre-mixed with air forming a blue…

Fluid Dynamics · Physics 2011-10-18 Preston Murray , Jonathon Pendlebury , Dale Tree , Tadd Truscott

The current WRF-Fire model starts the fire from a given ignition point at a given time. We want to start the model from a given fire perimeter at a given time instead. However, the fuel balance and the state of the atmosphere depend on the…

Atmospheric and Oceanic Physics · Physics 2011-07-20 Volodymyr Y. Kondratenko , Jonathan D. Beezley , Adam K. Kochanski , Jan Mandel

Few researches have studied simultaneous detection of smoke and flame accompanying fires due to their different physical natures that lead to uncertain fluid patterns. In this study, we collect a large image data set to re-label them as a…

Computer Vision and Pattern Recognition · Computer Science 2022-02-17 Hang Zhang , Su Yang , Hongyong Wang , zhongyan lu , helin sun