Extinction limits and structure of counterflow nonpremixed hydrogen-doped ammonia/air flames at elevated temperatures

Sun Choi, Seungro Lee and Oh Chae Kwon

Energy, 2015, vol. 85, issue C, 503-510

Abstract: The present study demonstrates the potential of hydrogen (H2)-doped ammonia (NH3) as a carbon-free fuel. The extinction limits, flame temperature and morphology of the counterflow nonpremixed NH3–H2/air flames at elevated temperatures and normal pressure are experimentally determined. Also, the detailed flame structure and the extinction limits are computed using a detailed kinetic mechanism. Results show that the blow-off limits, the concentration of radicals H, OH and O and the maximum flame temperature are enhanced with H2 substitution in NH3/air flames. This supports the potential of H2 as an additive for improving the reactivity and ignition of nonpremixed NH3/air flames and thus the potential of H2-doped NH3 as a carbon-free fuel. Meanwhile, the extinction limits (in terms of the mole fraction of NH3 in the fuel gas) and the maximum flame temperature are reduced with increasing strain rates, indicating that flames can sustain more NH3 at low strain rates. Also, it is observed that the blow-off limits and the maximum flame temperature are enhanced with increasing air temperature. Measured and predicted tendencies of the extinction limits and temperature for various conditions show encouraging agreement, but quantitative discrepancies among the measurements and predictions merit additional consideration in boundary condition modeling and the reaction mechanism.

Keywords: Ammonia; Hydrogen; Counterflow nonpremixed flames; Elevated temperatures; Extinction limits (search for similar items in EconPapers)
Date: 2015
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (13)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544215003709
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:85:y:2015:i:c:p:503-510

DOI: 10.1016/j.energy.2015.03.061

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().