Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls

This study focused on the unsteady behavior of fire whirls. A laboratory-scale fire whirl was generated, and temporal variations in flame height were measured from images taken by a high-speed camera and subjected to frequency analysis. The flame height fluctuations of the fire whirl also showed int...

Full description

Saved in:
Bibliographic Details
Main Authors: Mariko Watanabe, Yuya Oguri
Format: Article
Language:English
Published: Wiley 2025-01-01
Series:Journal of Combustion
Online Access:http://dx.doi.org/10.1155/jc/3035709
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850240368022388736
author Mariko Watanabe
Yuya Oguri
author_facet Mariko Watanabe
Yuya Oguri
author_sort Mariko Watanabe
collection DOAJ
description This study focused on the unsteady behavior of fire whirls. A laboratory-scale fire whirl was generated, and temporal variations in flame height were measured from images taken by a high-speed camera and subjected to frequency analysis. The flame height fluctuations of the fire whirl also showed intermittent behavior, such as the puffing of a pool flame. However, the period and amplitude were irregular compared to the pool flame. In addition, the fire whirl exhibited a greater amplitude spectrum at higher frequencies than the pool flame. To investigate the velocity distribution in the horizontal plane, particle image velocimetry (PIV) was employed. The results demonstrated that the mean velocity increased from the outer radial direction toward the inner radial direction, peaked, and decreased. Conversely, the coefficient of velocity variation decreased from the outer to the inner radial direction, exhibited a minimum, and then increased. Finally, the flame was photographed from horizontal and vertical directions under two conditions with different flow velocities from the fan to generate the fire whirl. Image analysis was employed to investigate the relationship between the center position of the flame and the flame height. The results demonstrated that under conditions where the flow velocity from the fan was low, the fire whirl was intermittent and moved following the circular path drawn by the swirling flow, exhibiting unstable behavior. Furthermore, the flame height was lower when the center of the flame was further from the liquid fuel pool.
format Article
id doaj-art-2a465f1dae7f476fa81a6dc3b9f2e8d0
institution OA Journals
issn 2090-1976
language English
publishDate 2025-01-01
publisher Wiley
record_format Article
series Journal of Combustion
spelling doaj-art-2a465f1dae7f476fa81a6dc3b9f2e8d02025-08-20T02:00:52ZengWileyJournal of Combustion2090-19762025-01-01202510.1155/jc/3035709Experimental Study of Spatiotemporal Variations in Lab-Scale Fire WhirlsMariko Watanabe0Yuya Oguri1Department of Engineering and Applied SciencesDepartment of Engineering and Applied SciencesThis study focused on the unsteady behavior of fire whirls. A laboratory-scale fire whirl was generated, and temporal variations in flame height were measured from images taken by a high-speed camera and subjected to frequency analysis. The flame height fluctuations of the fire whirl also showed intermittent behavior, such as the puffing of a pool flame. However, the period and amplitude were irregular compared to the pool flame. In addition, the fire whirl exhibited a greater amplitude spectrum at higher frequencies than the pool flame. To investigate the velocity distribution in the horizontal plane, particle image velocimetry (PIV) was employed. The results demonstrated that the mean velocity increased from the outer radial direction toward the inner radial direction, peaked, and decreased. Conversely, the coefficient of velocity variation decreased from the outer to the inner radial direction, exhibited a minimum, and then increased. Finally, the flame was photographed from horizontal and vertical directions under two conditions with different flow velocities from the fan to generate the fire whirl. Image analysis was employed to investigate the relationship between the center position of the flame and the flame height. The results demonstrated that under conditions where the flow velocity from the fan was low, the fire whirl was intermittent and moved following the circular path drawn by the swirling flow, exhibiting unstable behavior. Furthermore, the flame height was lower when the center of the flame was further from the liquid fuel pool.http://dx.doi.org/10.1155/jc/3035709
spellingShingle Mariko Watanabe
Yuya Oguri
Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
Journal of Combustion
title Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
title_full Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
title_fullStr Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
title_full_unstemmed Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
title_short Experimental Study of Spatiotemporal Variations in Lab-Scale Fire Whirls
title_sort experimental study of spatiotemporal variations in lab scale fire whirls
url http://dx.doi.org/10.1155/jc/3035709
work_keys_str_mv AT marikowatanabe experimentalstudyofspatiotemporalvariationsinlabscalefirewhirls
AT yuyaoguri experimentalstudyofspatiotemporalvariationsinlabscalefirewhirls