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Large-Scale Particle Image Velocimetry Measurements of a Fire-Induced Doorway Flow.


pdf icon Large-Scale Particle Image Velocimetry Measurements of a Fire-Induced Doorway Flow. (162 K)
Bryant, R. A.; Johnsson, E. L.

Chemical and Physical Processes in Combustion. Technical Meeting, 2005. Proceedings. Combustion Institute/Eastern States Section. November 13-15, 2005, Orlando, FL, 178-180 pp, 2005.

Keywords:

combustion; doorways; ventilation; fire behavior; experiments; velocity; room burns

Abstract:

Quantifying the ventilation available to a room fire is an important step to understanding fire behavior. The fresh air that moves into an enclosure provides the oxygen necessary to support the combustion while also serving to moderate the temperature of the compartment. The hot fire gases that move out of an enclosure transfer heat and combustion products from the localized point of the fire to remote locations within a built structure. Mass flow rate is the parameter typically used to quantify the ventilation for a fire within a room. Due to the three dimensional nature of flow through vents, a full mapping of the velocity and density fields is necessary to determine the mass flow rate. Early treatments quantifying fire induced flow through vents relied on Bernoulli's equation and a hydraulics-orifice approach, therefore only a few well placed pressure and temperature measurements were required. Later treatments were improved by adding vertical arrays of pressure and temperature measurements and scanning them across the vents in order to address the three dimensional nature of the flows.