THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

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Suppressing the thermal decomposition of forest fuel using the different water spraying schemes

ABSTRACT
This article presents the main findings of the experimental research into the fire suppression by continuous spraying of water over the combustion zone and by pulsed liquid aerosol delivery according to two schemes. The test samples contained either birch leaves only or mixed of forest fuel (leaves, twigs and needles). We monitored the temperature in the fuel bed and used thermocouple readings to determine the conditions and characteristics of suppressing the combustion and thermal decomposition of the material. Using optical methods and high-speed recording, we obtained the parameters of sprayed liquid flow as well as the processes involved in the interaction between liquid aerosol and the decomposing forest fuel. The experimental study helped us establish how much time and quenching liquid is sufficient to suppress the forest fuel combustion. Furthermore, we determined the influence of the forest fuel volume on the conditions and characteristics of the processes under study. Finally, we identified the main physical principles of the thermal decomposition of forest fuel when using the proposed approaches to spraying water into the combustion zone. The research findings enable the optimization of aerial firefighting in terms of wildfire containment and suppression.
KEYWORDS
PAPER SUBMITTED: 2018-04-21
PAPER REVISED: 2018-12-11
PAPER ACCEPTED: 2018-12-21
PUBLISHED ONLINE: 2019-01-13
DOI REFERENCE: https://doi.org/10.2298/TSCI180421006Z
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