Results 271 to 280 of about 82,402 (301)

Sound Generated by Cellular Flames

1991
It has been observed that flames propagating in tubes can spontaneously produce acoustic oscillations (Mallard and le Chatelier1). Rayleigh2 gave a general criterion for acoustic amplification by any local heat source: When heat is released locally and periodically in a gaseous medium, an acoustic oscillation is amplified if the oscillating components ...
Pierre Pelcé, Daniel Rochwerger
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Gravitational effects on cellular flame structure

Symposium (International) on Combustion, 1991
An experimental investigation has been conducted of the effect of gravity on the structure of downwardly propagating, cellular premixed propane-oxygen-nitrogen flames anchored on a water-cooled porous-plug burner. The flame is subjected to microgravity conditions in the NASA Lewis 2.2-second drop tower, and flame characteristics are recorded on high ...
C.M. Dunsky, A.C. Fernandez-Pello
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The cellular flame instability of ammonia/propane laminar flames at elevated pressures

Fuel
William L Roberts, Omar Z Arab
exaly   +2 more sources

Detailed numerical simulations of cellular flames

Symposium (International) on Combustion, 1989
Time-dependent, two-dimensional simulations of perturbed premixed laminar flames have been used to study the development of cellular structures in rich and lean hydrogen flames. The model includes detailed hydrogen-oxygen combustion with 24 elementary reactions of eight reactive species and a nitrogen diluent, molecular diffusion of all species ...
G. Patnaik, K. Kailasanath, E.S. Oran, K.J. Laskey   +3 more
openaire   +1 more source

On disintegration of near-limit cellular flames

Physics Letters A, 2003
A strongly non-linear geometrically-invariant model for the dynamics of near-limit cellular flame is proposed, where the flame evolution is governed by a system of equations for the flame interface and its temperature. The model generalizes its earlier weakly non-linear version pertinent to a mildly perturbed planar flame.
Michael L Frankel, Peter V Gordon, Gregory I Sivashinsky   +2 more
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Expanding Flames May Delay the Transition to Cellular Structures

SIAM Journal on Applied Mathematics, 1984
We derive a general equation for the evolution of flame fronts in weakly nonuniform flows. The equation is restricted to a particular range of Lewis numbers and describes the transition to cellular structures. This transition is analyzed for an expanding curved flame.
Matalon, Moshe, Erneux, Thomas
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Cellular flame structure and turbulent combustion

Combustion, Explosion and Shock Waves, 1982
Knowledge of flame interaction with perturbation of the surrounding medium is insufficient. This study investigates various parameters and methods for clarifying the combustion mechanism. The conditions for the appearance of a cellular structure were formed by analysis of diffusion phenomenon.
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Diffusional-Thermal Theory of Cellular Flames

Combustion Science and Technology, 1977
abstract It is shown that the formation of cellular structure in a flame is conditioned by diffusion and heat conduction effects and is independent of the hydrodynamics of the perturbed flame. It is proved that cellular flames are formed only when a sufficiently light reactant of the combustible mixture is present in a low concentration. If there is an
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Cellular flame structures and thermal characteristics of axi-symmetric ceiling fires: An experimental study and scaling analysis

Combustion and Flame, 2021
Longhua Hu, Xiaolei Zhang, Kazunori Kuwana   +2 more
exaly  

Ratcheting Motion of Concentric Rings in Cellular Flames

Physical Review Letters, 1996
, Gorman, , el-Hamdi, , Pearson, , Robbins   +3 more
openaire   +2 more sources