Cataloging Information
Fire Prediction
Heating of unburned fuel by attached flames and plume of a wildfire can produce high spread rates that have resulted in firefighter fatalities worldwide. Qualitative flow fields of the plume of a gas burner embedded in a table tilted to 0°, 10°, 20°, and 30° above horizontal were imaged using the retroreflective shadowgraph technique as a means to understand plume attachment and related behavior. Tilting of the plume in the uphill direction for all non-zero slopes was explained by an imbalance in the flow of air entrained into the plume. Reversal in direction of fluid flow uphill from the flame front was shown to occur when buoyancy forces overwhelmed entrainment flow momentum. Flame and plume attachment was explained as being caused by uphill flow of hot combustion gas driven by a combination of buoyancy and an uphill pressure gradient.