Computational smoldering combustion: Predicting the roles of moisture and inert contents in peat wildfires
File(s)
Published version
Author(s)
Huang, Xinyan
Rein, Guillermo
Chen, Haixiang
Type
Journal Article
Abstract
Abstract Smoldering combustion is the slow, low-temperature, flameless burning of porous fuels and the most persistent type of combustion. It is the driving phenomenon of wildfires in peatlands, like those causing haze episodes in Southeast Asia and Northeast Europe, but is poorly understood. In this work, we develop a comprehensive 1-D model of a reactive porous media, using the open-source code Gpyro, to investigate smoldering combustion of natural fuels with an emphasis on the roles of the moisture and inert contents. The model solves the species, momentum, and energy conservation equations and includes heterogeneous chemical reactions. A previously developed 5-step reaction scheme for peat, including evaporation of water, is adopted to describe the drying, thermal and oxidative degradation during the smoldering combustion. The model predicts the transient temperature, species, and reaction profiles during ignition, spread, and extinction. The predicted smoldering thresholds related to the critical moisture and inorganic contents for ignition show a good agreement with the experimental results in the literature for a wide range of peat types and organic soils. The influences of the kinetic parameters, physical properties, and ignition protocol are investigated. This is the first time that a physics-based model of smoldering peat fires is developed, thus helping to understand this important natural and widespread phenomenon.
Date Issued
2015-01-01
Date Acceptance
2014-06-01
Citation
Proceedings of the Combustion Institute, 2015, 35 (3), pp.2673-2681
ISSN
0082-0784
Publisher
Elsevier
Start Page
2673
End Page
2681
Journal / Book Title
Proceedings of the Combustion Institute
Volume
35
Issue
3
Copyright Statement
© 2014 The Authors. Published by Elsevier Inc. on behalf of The Combustion Institute. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/).
License URL
Identifier
http://www.sciencedirect.com/science/article/pii/S1540748914000510
Subjects
Computational
Drying
Peat wildfires
Smoldering combustion
Smoldering thresholds
Notes
Abstract Smoldering combustion is the slow, low-temperature, flameless burning of porous fuels and the most persistent type of combustion. It is the driving phenomenon of wildfires in peatlands, like those causing haze episodes in Southeast Asia and Northeast Europe, but is poorly understood. In this work, we develop a comprehensive 1-D model of a reactive porous media, using the open-source code Gpyro, to investigate smoldering combustion of natural fuels with an emphasis on the roles of the moisture and inert contents. The model solves the species, momentum, and energy conservation equations and includes heterogeneous chemical reactions. A previously developed 5-step reaction scheme for peat, including evaporation of water, is adopted to describe the drying, thermal and oxidative degradation during the smoldering combustion. The model predicts the transient temperature, species, and reaction profiles during ignition, spread, and extinction. The predicted smoldering thresholds related to the critical moisture and inorganic contents for ignition show a good agreement with the experimental results in the literature for a wide range of peat types and organic soils. The influences of the kinetic parameters, physical properties, and ignition protocol are investigated. This is the first time that a physics-based model of smoldering peat fires is developed, thus helping to understand this important natural and widespread phenomenon.
Publication Status
Published
Date Publish Online
2014-06-25