@article{ref1,
title="A Computational Study of Extinguishment and Enhancement of Propane Cup-Burner Flames by Halon and Alternative Agents",
journal="Fire safety journal",
year="2017",
author="Takahashi, Fumiaki and Katta, Viswanath and Linteris, Gregory and Babushok, Valeri",
volume="91",
number="",
pages="688-694",
abstract="Computations of cup-burner flames in normal gravity have been performed using propane as the fuel to reveal the combustion inhibition and enhancement by the CF<sub>3</sub>Br (halon 1301) and potential alternative fire-extinguishing agents (C<sub>2</sub>HF<sub>5</sub>, C<sub>2</sub>HF<sub>3</sub>Cl<sub>2</sub>, and C<sub>3</sub>H<sub>2</sub>F<sub>3</sub>Br). The time-dependent, two-dimensional numerical code used includes a detailed kinetic model (up to 241 species and 3918 reactions), diffusive transport, and a gray-gas radiation model. The peak reactivity spot (i.e., reaction kernel) at the flame base stabilizes a trailing flame, which is inclined inwardly by a buoyancy-induced entrainment flow. As the volume fraction of agent in the coflow increases gradually, the <i>premixed</i>-like reaction kernel weakens, thus inducing the flame base detachment from the burner rim and blowoff-type extinguishment eventually. The <i>two-zone</i> flame structure (with two heat-release-rate peaks) is formed in the trailing <i>diffusion</i> flame. The H<sub>2</sub>O formed in the inner zone is converted further, primarily in the outer zone, to HF and CF<sub>2</sub>O through exothermic reactions most significantly with the C<sub>2</sub>HF<sub>5</sub> addition. The total heat release of the entire flame decreases (inhibiting) for CF<sub>3</sub>Br but increases (enhancing) for the halon alternative agents, particularly C<sub>2</sub>HF<sub>5</sub> and C<sub>2</sub>HF<sub>3</sub>Cl<sub>2</sub>. Addition of C<sub>2</sub>HF<sub>5</sub> results in unusual (non-chain branching) reactions.<p /> <p>Language: en</p>",
language="en",
issn="0379-7112",
doi="10.1016/j.firesaf.2017.04.010",
url="http://dx.doi.org/10.1016/j.firesaf.2017.04.010"
}