Enclosure and Facade Fires: Physics and Applications

Abstract

Facade fires being a disastrous hazard for high rise building, as several historical and recent incidents have shown, have attracted the interests of numerous fire scientists, engineers and regulators. This work has as an objective to present issues in this area that are challenging and need further attention. It focuses on characterizing the flame height and heat fluxes from facade flames produced from under-ventilated enclosure fires on a facade that is not flammable. Such an investigation is an important consideration for practical applications as well as a prerequisite for examining fire spread on flammable facades and for designing a test for modern facade assemblies. The mass pyrolysis rates and burning of real fuels are discussed in under ventilated enclosures, rectangular or corridor like, for various openings presenting the current state and some critical issues. Facade flames are analyzed from experiments using gaseous burners to have control on the fuel supply rate by introducing physical length scales for the opening geometries to model flame heights and heat fluxes. An important parameter for the facade flames is the excess heat release rate of the fuel burning outside the enclosure. Finally, applications for facade flames with sidewalls and facade flames from two openings are presented.