Publications

@article{Hakes2019,

title = {Thermal characterization of firebrand piles},

author = {Raquel S P Hakes and Hamed Salehizadeh and Matthew J Weston-Dawkes and Michael J Gollner},

url = {https://linkinghub.elsevier.com/retrieve/pii/S0379711218302698},

doi = {10.1016/j.firesaf.2018.10.002},

issn = {03797112},

year  = {2019},

date = {2019-03-01},

journal = {Fire Safety Journal},

volume = {104},

pages = {34--42},

publisher = {Elsevier Ltd},

abstract = {The cause of the majority of structure losses in wildland-urban interface fires is ignition via firebrands, small pieces of burning material generated from burning vegetation and structures. To understand the mechanism of these losses, small-scale experiments designed to capture heating from firebrand piles and to describe the process of ignition were conducted using laboratory-fabricated cylindrical wooden firebrands. Two heat flux measurement methods were compared, and the influences of firebrand diameter, pile mass, and wind on heating from firebrand piles were explored. Diameter had little effect on heating, pile mass a moderate effect, and wind a large effect. Peak heat fluxes showed distinct differences between heat fluxes produced by firebrand piles as opposed to individual firebrands, which have been studied exclusively on the small-scale in the past. Above a critical mass, piles did not produce higher heat fluxes; however, they heated fuels for an increasingly longer duration and over a larger area. Water-cooled heat flux gauges provided reliable heat flux measurements for large firebrand piles and an array of thin-skin calorimeters indicated significant spatial variation in heat flux. A recipient fuel transitioned from smoldering to flaming under an adequate wind speed soon after a firebrand pile was deposited on its surface.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Caton-Kerr2019,

title = {Firebrand Generation From Thermally-Degraded Cylindrical Wooden Dowels},

author = {Sara E Caton-Kerr and Ali Tohidi and Michael J Gollner},

doi = {10.3389/fmech.2019.00032},

issn = {2297-3079},

year  = {2019},

date = {2019-01-01},

journal = {Frontiers in Mechanical Engineering},

volume = {5},

number = {June},

pages = {1--12},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tang2019,

title = {An Experimental Study of Intermittent Heating Frequencies From Wind-Driven Flames},

author = {Wei Tang and Mark Finney and Sara McAllister and Michael Gollner},

doi = {10.3389/fmech.2019.00034},

issn = {2297-3079},

year  = {2019},

date = {2019-01-01},

journal = {Frontiers in Mechanical Engineering},

volume = {5},

number = {June},

pages = {1--9},

abstract = {An experimental study was conducted to understand the intermittent heating behavior downstream of a gaseous line burner under forced flow conditions. While previous studies have addressed time-averaged properties, here measurements of the flame location and intermittent heat flux profile help to give a time-dependent picture of downstream heating from the flame, useful for understanding wind-driven flame spread. Two frequencies are extracted from experiments, the maximum flame forward pulsation frequency in the direction of the wind, which helps describe the motion of the flame, and the local flame-fuel contact frequency in the flame region, which is useful in calculating the actual heat flux that can be received by the unburnt fuel via direct flame contact. The forward pulsation frequency is obtained through video analysis using a variable interval time average (VITA) method. Scaling analysis indicates that the flame forward pulsation frequency varies as a power-law function of the Froude number and fire heat-release rate, . For the local flame-fuel contact frequency, it is found that the non-dimensional flame-fuel contact frequency remains approximately constant before the local Rix reaches 1, e.g., attached flames. When Rixtextgreater1, decreases with local as Rix flames lift up. A piece-wise function was proposed to predict the local flame-fuel contact frequency including the two Rix scenarios. Information from this study helps to shed light on the intermittent behavior of flames under wind, which may be a critical factor in explaining the mechanisms of forward flame spread in wildland and other similar wind-driven fires.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}