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Ignition and combustion of n-heptane droplets in carbon dioxide enriched environments ☆

Published on Mar 1, 2010in International Communications in Heat and Mass Transfer4.127
· DOI :10.1016/j.icheatmasstransfer.2009.10.006
Justin Dzik1
Estimated H-index: 1
(Glenn Research Center),
Vedha Nayagam12
Estimated H-index: 12
(Glenn Research Center),
Forman A. Williams58
Estimated H-index: 58
(UCSD: University of California, San Diego)
Abstract
The ignition process and burning characteristics of fiber-supported n-heptane fuel droplets in carbon dioxide enriched and varying pressure environments have been studied under normal gravity. Measured values of droplet burning rates, flame dimensions, broad-band radiant emission, and ignition times were compared to droplets burning in standard air conditions. The burning rate constants increased with increasing carbon dioxide concentration or pressure. For 21% ambient oxygen concentration ignition was achieved for carbon dioxide concentrations up to 46% with the remaining being nitrogen. The experimental burning rates were compared to existing theoretical models. A flammability map for n-heptane burning under normal gravity as a function of carbon dioxide concentration and pressure was also developed using these results.
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