Thermal Characterization of Firebrand Piles

Abstract

Over the past several decades, the severity of wildland-urban interface (WUI) fires has increased drastically, resulting in thousands of structures lost globally each year. The cause of the majority of structure losses is ignition via firebrands, small pieces of burning material which are generated from burning vegetation and structures. In this thesis, a methodology for studying the heating to recipient fuels by firebrands is developed. Small-scale experiments designed to capture heating from firebrand piles and the process of ignition were conducted using laboratory-fabricated cylindrical wooden firebrands. The methodology compares two heat flux measurement methods. Experimental results compare the effects of varying firebrand diameter, pile mass, and wind speed. An ignition condition is described using temperature and heat flux.