Fundamentals of window-ejected fire plumes from under-ventilated compartment fires: Recent progresses and perspectives

This paper intends to provide a comprehensive state-of-art review of recent progresses and to formulate perspectives on window-ejected fire plumes, originating from under-ventilated compartment fires (known as ‘Regime I’ fires). Various external boundary conditions are considered, as they contribute to the fire and plume dynamics, and as such affect decisions on fire prevention and firefighting. Hence this is an important fire combustion topic of both fundamental and practical significance. After discussing the general fundamentals, the paper focuses particularly on recent progresses on quantifying the ejected fire plume behavior: constrained by the presence of walls; at sub-atmospheric pressure (for fires at high altitudes) and under complex flow conditions caused by wind. Experiments, theoretical scaling analysis and basic models are reviewed. The key points cover systematically: the compartment fire evolution (and hence criteria for flame ejection through the window); flame interaction and merging behavior from two windows; air entrainment mechanisms and characteristic parameters (flame structure/dimensions, temperature profile and heat flux) of window-ejected fire plumes. Meanwhile, the limitations of present research and future challenges are also discussed.