Transport of Carbon Monoxide From a Burning Compartment Located on the Side of a Hallway.
Transport of Carbon Monoxide From a Burning Compartment
Located on the Side of a Hallway.
(781 K)
Lattimer, B. Y.; Vandsburger, U.; Roby, R. J.
Combustion Institute, Symposium (International) on
Combustion, 26th. Proceedings. Volume 1. July
28-August 2, 1996, Napoli, Italy, Combustion Institute,
Pittsburgh, PA, 1541-1547 pp, 1996.
Sponsor:
National Institute of Standards and Technology,
Gaithersburg, MD
Keywords:
combustion; carbon monoxide; hallways
Abstract:
An experimental study was conducted to investigate the
transport of high concentrations of carbon monoxide (CO)
from a burning compartment located on the side of a
hallway. Opening sizes of 0.04 and 0.12 m2 were used to
vary the ability of the jet of fire products entering
the hallway to entrain surrounding gases. By
controlling the depth of the upper layer of
oxygen-deficient combustion gases accumulated in the
hallway during preflashover, the oxygen concentration of
the gases entrained into the jet of fire products
entering the hallway was varied. An increase in the
upper-layer depth resulted in higher CO and UHC yields
and lower CO2 yields. When the depth of the layer fell
below the bottom of the opening, downstream CO yields
were found to increase to levels equivalent to or
greater than yields measured inside the compartment,
with the highest yields measured in experiments with
external burning. Using the external burning as a flow
visualization tool, the gases were observed to be
transported nonuniformly down the hallway when the
burning compartment was on the side. The bulk flow of
the gases was to cross the hallway and then flow down
the side of the hallway opposite the compartment. This
nonuniformity in gas transport within the hallway was
also evident in spatial and temporal measurements of
species concentrations and temperature. In the hallway,
during the postflashover period of the compartment fire,
concentrations of CO greater than 2.0% were measured at
locations along the wall opposite the compartment, while
CO concentrations of only 0.8% were measured on the
compartment side of the hallway. The data presented
provides the first explanation for the tragic results of
fires in health care facilities where CO inhalation was
responsible for numerous deaths, and points to the
necessary directions for reliable predictive tools.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899