Sage Journals: Discover world-class research

Abstract

This paper describes the results of an experimental investigation aimed at establishing the nature of flame propagation within stratified mixtures of methane and air in circular tubes. Flames propagating upwards, horizontally, and downwards through concentration gradients of up to 3 percent by volume of methane per meter were studied. The velocities of decelerated flames were observed to be up to 70% higher than the corresponding flame velocities under homogeneous mixture conditions. Empirical correlations were then developed for flame velocities within stratified mixtures in terms of corresponding velocities under homogeneous conditions, concentration gradients, and homogeneous flame velocities corresponding to mixture concentrations at the ignition point.

Get full access to this article

View all access options for this article.

References

Karim, G. and Tsang, P. , "Flame Propagation Through Atmospheres Involving Concentration Gradients Formed by Mass Transfer Phenomena," ASME Trans., J. Fluids Engr., p. 615 ( 1975).

Hirano, T. , et al, "Flame Propagation Through Mixtures with Concentration Gradients," Sixteenth Symposium (Int.) on Combustion, p. 1307, The Combustion Institute ( 1977).

Kaptein, M. and Hermance, C. , "Horizontal Propagation of Laminar Flames Through Vertically Diffusing Mixtures Above a Ground Plane," Sixteenth Symposium (Int.) on Combustion, p. 1295, The Combustion Institute (1977).

Liebman, I. , et al, "Investigation of Flame Propagation Characteristics in Layered Gas Mixtures," U.S. Dept. of the Interior, Bureau of Mines, Report of Investigation 7078 (February 1969).

Phillips, H. , "Flame in a Buoyant Methane Layer," Tenth Symposium (Int.) on Combustion, p. 1277, The Combustion Institute ( 1965).

Badr, O. and Karim, G. , "An Experimental Approach for Investigating Laminar Flame Propagation in Methane-Air Mixtures Within Circular Tubes," J. of Fire and Flammability, V. 11, p. 106 (1980).

Badr, O. and Karim, G. , "An Experimental Study of the Instability of Flame Fronts Propagating in Circular Tubes," A Paper Presented at the Annual Meeting, Eastern States Section, The Combustion Institute , Miami, Florida (November 1978).

Coward, H.F. and Hartwell, F.J. , "Studies in the Mechanism of Flame Movements ," Part 1, Chem. Soc. Lon. J., p. 1996 (1932).

Badr, O. , "Fire Spread Characteristics Through Homogeneous and Stratified Combustible Mixtures Within Tubes," Ph.D. Thesis, Dept. of Mech. Engr ., The University of Calgary (1977 ).

10.

Tsang, P. , "Flame Propagation Through methane-Air Mixtures Involving Concentration Gradients Formed by Mass Transfer Phenomena," Ph.D. Thesis, Dept. of Mech. Engr., The University of Calgary (1974).

11.

Walpole, R.E. and Myers, R.H. , "Probability and Statistics of Engineers and Scientists," MacMillan Publishing Co., Inc., p. 282 (1972).

Flame Propagation in Stratified Methane-Air Mixtures

Abstract

Get full access to this article

References