Analysis of the mechanisms of stable flame propagation in a cross-flow reactor

Authors: Yarkov A.V.
Published in issue: #9(62)/2021
DOI: 10.18698/2541-8009-2021-9-734
Category: Physics | Chapter: Chemical physics, combustion and explosion
Keywords: flow reactor, combustion stabilization, cross flow, methane-air mixture, flame front propagation velocity, flame interaction with vortices
Published: 08.09.2021

Experimental data were processed and mathematical modeling of the flame propagation process in a stoichiometric methane-air mixture in a flow reactor with an organized cross-flow of a fresh mixture was carried out in order to identify the main mechanisms responsible for the stable propagation of the flame front. The processing of the experimental data showed the nonlinear character of the dependence of the flame front average velocity on the volumetric flow rate of the mixture. In this case, in contrast to the corresponding data for the case without a transverse flow, an increase in the average front velocity is observed with an increase in the volumetric flow rate of the mixture. Numerical modeling of such a system has shown that in the regions of gas supply in the transverse direction, vortex structures are formed in the channel, the interaction of the flame with which contributes to an increase in the flame surface area and combustion intensification. The conducted studies of the flame propagation characteristics in a flow-through reactor with a cross-flow expand the understanding of the mechanisms of stable flame propagation in a flow-through reactor and, in particular, mechanisms of flame interaction with vortex structures. On the other hand, the organization of a more sustainable combustion regime is the basis for improving energy efficiency and environmental safety when using gaseous fuels.

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