Dynamics of lean premixed flames stabilized on a meso-scale bluff-body in an unconfined flow field

Yu Jeong Kim, Bok Jik Lee, Hong G. Im

Research output: Contribution to journalArticlepeer-review

3 Scopus citations

Abstract

Two-dimensional direct numerical simulations were conducted to investigate the dynamics of lean premixed flames stabilized on a meso-scale bluff-body in hydrogen-air and syngas-air mixtures. To eliminate the flow confinement effect due to the narrow channel, a larger domain size at twenty times the bluff-body dimension was used in the new simulations. Flame/flow dynamics were examined as the mean inflow velocity is incrementally raised until blow-off occurs. As the mean inflow velocity is increased, several distinct modes in the flame shape and fluctuation patterns were observed. In contrast to our previous study with a narrow channel, the onset of local extinction was observed during the asymmetric vortex shedding mode. Consequently, the flame stabilization and blow-off behavior was found to be dictated by the combined effects of the hot product gas pocket entrained into the extinction zone and the ability to auto-ignite the mixture within the given residence time corresponding to the lateral flame fluctuations. A proper time scale analysis is attempted to characterize the flame blow-off mechanism, which turns out to be consistent with the classic theory of Zukoski and Marble.
Original languageEnglish (US)
Pages (from-to)48
JournalMathematical Modelling of Natural Phenomena
Volume13
Issue number6
DOIs
StatePublished - Sep 27 2018

Fingerprint

Dive into the research topics of 'Dynamics of lean premixed flames stabilized on a meso-scale bluff-body in an unconfined flow field'. Together they form a unique fingerprint.

Cite this