Results 221 to 230 of about 29,687 (261)

The thick flame asymptotic limit and Damköhler's hypothesis

Combustion Theory and Modelling, 2002
We derive analytical expressions for the burning rate of a flame propagating in a prescribed steady parallel flow whose scale is much smaller than the laminar flame thickness. In this specific context, the asymptotic results can be viewed as an analytical test of Damkoḧler's hypothesis relating to the influence of the small scales in the flow on the ...
Daou, J.; id_orcid 0000-0002-7793-1765, Dold, J., Matalon, M.   +2 more
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The thickness of laminar flames

Combustion and Flame, 1984
The thickness of a combustion flame is modeled numerically on the basis of the energy equation. Consideration is limited to a steady-state one-dimensional laminar flame. Calculations are presented for the thickness of a pure thermal flame and air-methane, air-propane, and air-hydrogen flames.
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Premixed flame propagation in an optically thick gas

AIAA Journal, 1993
Flame propagation in both the optically thin and the optically thick regime of radiative transport was studied experimentally using particle-laden gas mixtures. Data on flame shapes, propagation rates, peak pressure, maximum rate of pressure rise, and thermal decay in the burned gases are consistent with the hypothesis that, at low particle loadings ...
Angel Abbud-Madrid, Paul D. Ronney
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Velocity of weakly turbulent flames of finite thickness

Combustion Theory and Modelling, 2005
The velocity increase of a weakly turbulent flame of finite thickness is investigated using analytical theory developed in previous papers.
V. Akkerman, V. Bychkov
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Ignitor and Thickness Effects on Upward Flame Spread

Fire Technology, 1998
The effects of a material's ignitor characteristics and burning duration on upward wall flame spread are investigated. The ignitor is represented as an energy line source. Its energy release rate and its duration after ignition are considered. The material is represented as a finite, thick noncharring material with properties representative of ...
J. Q. Quintiere, C. H. Lee
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Effect of porosity and element thickness on flame quenching for in-line crimped-ribbon flame arresters

Journal of Loss Prevention in the Process Industries, 2017
Abstract An experimental system consisting of a pipe with a variable length and diameter and different types of crimped-ribbon flame arresters, was set up to investigate the effect of physical parameters on the flame propagation and quenching processes of propane, ethylene and hydrogen/air mixtures.
Shaochen Sun, Gang Liu, Junxuan Liu, Chen Ye, Jingjie Ren, Mingshu Bi   +5 more
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The Thickness Distribution of OH Regions in a Turbulent Diffusion Flame

Combustion Science and Technology, 1993
Abstract Abstract–The OH radicals in a hydrogen diffusion flame burning in ambient air were visualized using planar laser-induced fluorescence. Local thicknesses of the OH regions were measured at three downstream distances. Measurements show that the thickness is distributed approximately according to a lognormal probability density function.
A. W. JOHNSON, M. WINTER
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Turbulent scales smaller than the flame thickness

Physical Review E, 1999
We study in this paper the effect of turbulent scales smaller than the premixed flame thickness on flame propagation and structure. We compare our numerical results to existing theories of flame broadening, showing that the apparent Lewis number tends to unity for very high forcings, but that the small scale forcing can generate a large-scale curvature
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Effect of thickness of diffusion-temperature layer on flame height

Combustion, Explosion and Shock Waves, 1968
1. Periodic variation of the thickness of the diffusion-temperature layer causes periodic oscillations of the flame height. 2. The mechanism of sinusoidal or near-sinusoidal oscillation of the flame height can be explained, at least qualitatively, purely in terms of molecular radial diffusion of oxygen.
V. N. Podymov, I. F. Chuchalin
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Investigation of Light Interaction With Transient Expanding Thick Flames

Energy Conversion and Resources: Fuels and Combustion Technology, Energy, Nuclear Engineering, and Solar Engineering, 2003
Optical behavior of spherical flames has been investigated using Shadowgraph method. A mathematical model has been developed to predict the intensity profile of refracted light beams interacting with a transient expanding thick flame. Experimental facilities have been built to visualize transient expanding spherical flames.
Farzan Parsinejad, Hameed Metghalchi
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