Observations of energy transport and rate of spreads from low-intensity fires in longleaf pine habitat-RxCADRE 2012
Wildland fire rate of spread (ROS) and intensity are determined by the mode and magnitude of energy transport from the flames to the unburned fuels. Measurements of radiant and convective heating and cooling from experimental fires are reported here. Sensors were located nominally 0.5mabove ground level. Flame heights varied from 0.3 to 1.8 m and flaming zone depth varied from 0.3 to 3.0 m. Fire ROS derived from observations of fire transit time between sensors was 0.10 to 0.48 m s 1. ROS derived from ocular estimates reached 0.51 m s 1 for heading fire and 0.25 m s 1 for backing fire. Measurements of peak radiant and total energy incident on the sensors during flame presence reached 18.8 and 36.7kWm 2 respectively. Peak air temperatures reached 11598C. Calculated fire radiative energy varied from 7 to 162 kJ m 2 and fire total energy varied from 3 to 261 kJ m 2. Measurements of flame emissive power peaked at 95 kW m 2. Average horizontal air flow in the direction of flame spread immediately before, during, and shortly after the flame arrival reached 8.8 m s 1, with reverse drafts of 1.5 m s 1; vertical velocities varied from 9.9 m s 1 upward flow to 4.5m s 1 downward flow. The observations from these fires contribute to the overall understanding of energy transport in wildland fires.
You can order print copies of our publications through our publication ordering system. Make a note of the publication you wish to request, and visit our Publication Order Site.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unuseable.
- To view this article, download the latest version of Adobe Acrobat Reader.