A computational study of preferential diffusion and scalar transport in nonpremixed hydrogen-air flame

Jiang, Jieyu and Jiang, Xi and Zhu, Min (2015) A computational study of preferential diffusion and scalar transport in nonpremixed hydrogen-air flame. International Journal of Hydrogen Energy, 40 (45). pp. 15709-15722. ISSN 0360-3199

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Abstract

The nonpremixed hydrogen-air reacting flow is simulated using three-dimensional direct numerical simulation coupled with flamelet generated manifolds based on detailed chemical kinetics. From the comparisons between one computational case taking into account preferential diffusion and another case with unity Lewis number assumption, the instantaneous results show that the flow is more vortical in the absence of preferential diffusion. This indicates that preferential diffusion may smooth the flame under certain circumstances when coupled with the intrinsic hydrodynamic instability. The flame compositional structures are also influenced by preferential diffusion in a significant manner. Further, the statistical information suggests that turbulent scalar flux is affected by preferential diffusion. The phenomenon of counter-gradient diffusion of both the conserved and non-conserved scalars can be detected for the two cases. The gradient model for scalar closure is found to be incapable of accurately predicting the scalar transport in nonpremixed hydrogen flames.

Item Type:
Journal Article
Journal or Publication Title:
International Journal of Hydrogen Energy
Additional Information:
This is the author’s version of a work that was accepted for publication in International Journal of Hydrogen Energy. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Journal of Hydrogen Energy, 40 (45), 15709-15722 2015 DOI: 10.1016/j.ijhydene.2015.08.112
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2100/2105
Subjects:
ID Code:
77922
Deposited By:
Deposited On:
26 Jan 2016 09:54
Refereed?:
Yes
Published?:
Published
Last Modified:
09 Apr 2020 02:31