Flame spread over fuel films in opposed gas flow
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The effect of the velocity of forced oxidizer flow on the pattern and velocity of flame spread over a fuel film was experimentally studied, and the limiting conditions of steady-state flame propagation were determined. New experimental evidence was obtained for the validity of the previously proposed model of flame propagation in a thermally thin system. It was found that, in a thermally thin system at a certain value of the gas flow velocity, laminar flame propagation is followed by spin flame propagation in a narrow range of gas flow velocities, and then by quenching. In the laminar layer-by-layer propagation regime, the flame velocity does not depend on the average velocity of the opposed gas flow. The proposed model for the laminar layerby-layer flame propagation agrees with experiment taking into account the fuel film flow under the action of the Marangoni effect due to the condensed-phase temperature gradient.
Key wordsthermally thin system flame fuel film
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