THERMAL SCIENCE

International Scientific Journal

EFFECT OF RATIO BETWEEN INCOMING COOL AIR AND OUTGOING HOT GASES ON BEHAVIOUR OF COMPARTMENT FIRE

ABSTRACT
Many factors have an influence on the development of compartment fire notably on its heat release rate as well as on its capability to propagate and become a flashover situation. The main element which rapidly conveys fire from a compartment to another is hot smoke flowing out through openings of the compartment source of fire. The present work aims to experiment the impact of the variation of heat release rate of the source on the behavior of fire. So, five fire tests with different heat release rates were thus carried out in a reduced scale room. Temperature of burned gases inside the room, were measured during tests by sensors connected to a data acquisition system. Results revealed that temperature of burned gases as well as its content in CO, evolves differently according to two ranges of the incoming air/outgoing gases ratio. The first range of which the ratio is lower than 2, corresponds to the case where both parameters decrease rapidly. The second range of which the ratio is higher than 2, corresponds to the case where both parameters decrease moderately. The transition from the first to the second range, points out the passing from the ventilation-controlled fire to the fuel-controlled fire. A relation expressing the variation of the mass-flow rate of outgoing burned gases according to the heat release rate of the fire source has been given.
KEYWORDS
PAPER SUBMITTED: 2019-02-10
PAPER REVISED: 2019-08-08
PAPER ACCEPTED: 2019-08-15
PUBLISHED ONLINE: 2019-09-15
DOI REFERENCE: https://doi.org/10.2298/TSCI190210326Z
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2021, VOLUME 25, ISSUE Issue 1, PAGES [221 - 228]
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© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence