Fire downwind a flat surface entering a canyon by lateral spread

Abstract In this paper, we present an experimental study at laboratory scale of a wind driven fire entering a lateral canyon perpendicular to the main fire spread direction. This study is inspired on a multiple fatalities accident occurred in Armamar (Portugal), in 1985. The laboratory experiments show an eruptive fire behaviour inside the canyon. A rapid increase in the rate of spread and intensity of the fire is noticed when the fire enters the canyon, even though the wind is blowing perpendicular to the canyon axis. This increase is due to the presence of three factors: flow circulation inside the canyon, junction, and eruptive fire behaviours. The findings of this study contribute to better understand fire behaviour in complex terrain and therefore to improve personnel safety.