THERMAL SCIENCE

International Scientific Journal

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Burning rate of conduction-controlled ethanol pool fires under a ceiling

ABSTRACT
The burning characteristics of conduction-controlled pool fires under a ceiling have not been revealed in the past. In this paper, experiments on square ethanol pool fires with dimensions of 4, 6, and 8 cm under the ceiling of various heights were conducted to investigate the ceiling effect on the burning rate of conduction-controlled pool fires. Results show that when the ceiling close to the pool, the burning process exhibited an extra initial steady stage before its development stage in the burning process. Moreover, a flame-wrapping phenomenon was observed in the later period of this burning process. The pool rim wall temperature and mass burning rate exhibited an increase with the decreasing ceiling height. The rim wall temperature increase was pronounced in relative larger pool fires; however, the burning rate enhancement was prominent in relative smaller ones. The burning rate enhancement was found to be mainly attributed to the increase in pool rim wall temperature. A global factor was developed to correlate the mass burning increment with rim wall temperature increase and pool size, which was confirmed by experimental data.
KEYWORDS
PAPER SUBMITTED: 2017-03-10
PAPER REVISED: 2017-05-11
PAPER ACCEPTED: 2017-06-09
PUBLISHED ONLINE: 2017-07-08
DOI REFERENCE: https://doi.org/10.2298/TSCI170310156Z
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