Role of buoyant flame dynamics in wildfire spread

• DOI: 10.1073/pnas.1504498112
• Publication Date: 2015-07-17T02:45:02Z
• Authors: Mark A. Finney; Jack D. Cohen; Jason M. Forthofer; Sara S. McAllister; Michael J. Gollner; Daniel J. Gorham; Kozo Saito; Nelson K. Akafuah; Brittany A. Adam; Justin D. English
• Keywords: flame spread; Hot Temperature; Time Factors; Temperature; Wind; Convection; Texas; Fires; Imaging; 12. Responsible consumption; Physical Phenomena; convective heating; Imaging, Three-Dimensional; buoyant instability; 13. Climate action; Three-Dimensional; wildfires

Significance Wildfires burn millions of hectares per year on every inhabited continent, but the physical mechanism governing spread is not known. Models of wildfire spread are widely used for prediction, firefighter training, and ecological research but have assumed various formulations of known heat transfer processes (radiation and convection) absent a definitive theory of their organization. New experimental evidence reported here reveals how buoyancy generated by the fire induces vorticity and instabilities in the flame zone that control the convective heating needed to ignite fuel particles and produce spread.