The Formation of Stratified Combustible Mixtures in Closed Tubes by Molecular and Convective Diffusions

Abstract

This paper describes a theoretical study on the formation of stratified combustible mixtures in closed long vertical flame tubes. The concentration profiles of the fuel (methane) in air, just before ignition took place, were predicted using a one-dimensional model involving molecular and convective diffusional processes. Phenomenological and experimental justification of the one-dimensional assumption was given and some of the predicted data were compared with experiment for different test conditions. The model appears to have successfully predicted the concentration profiles in some situations where other models failed.