TY - JOUR
T1 - Assessment of Fire Engineering Design Correlations Used to Describe the Geometry and Thermal Characteristics of Externally Venting Flames
AU - Asimakopoulou, Eleni
AU - Kolaitis, Dionysios
AU - Founti, Maria
N1 - New member of staff at Ulster 1st February 2017
PY - 2017/3/31
Y1 - 2017/3/31
N2 - Externally venting flames (EVF) may emerge through openings in fully developed under-ventilated compartment fires, significantly increasing the risk of fire spreading to higher floors or adjacent buildings. Several fire engineering correlations have been developed, aiming to describe the main characteristics of EVF that affect the fire safety design aspects of a building, such as EVF geometry, EVF centreline temperature and EVF-induced heat flux to the façade elements. This work is motivated by recent literature reports suggesting that existing correlations, proposed in fire safety design guidelines (e.g. Eurocodes), cannot describe with sufficient accuracy the characteristics of EVF under realistic fire conditions. In this context, a wide range of EVF correlations are comparatively assessed and evaluated. Quantification of their predictive capabilities is achieved by means of comparison with measurements obtained in 30 different large-scale compartment-façade fire experiments, covering a broad range of heat release rates (2.8 MW to 10.3 MW), ventilation factor values (2.6 m5/2 to 11.53 m5/2) and ventilation conditions (no forced draught, forced draught). A detailed analysis of the obtained results and the respective errors corroborates the fact that many correlations significantly under-predict critical physical parameters, thus resulting in reduced (non-conservative) fire safety levels. The effect of commonly used assumptions (e.g. EVF envelope shape or model parameters for convective and radiative heat transfer calculations) on the accuracy of the predicted values is determined, aiming to highlight the potential to improve the fire engineering design correlations currently available.
AB - Externally venting flames (EVF) may emerge through openings in fully developed under-ventilated compartment fires, significantly increasing the risk of fire spreading to higher floors or adjacent buildings. Several fire engineering correlations have been developed, aiming to describe the main characteristics of EVF that affect the fire safety design aspects of a building, such as EVF geometry, EVF centreline temperature and EVF-induced heat flux to the façade elements. This work is motivated by recent literature reports suggesting that existing correlations, proposed in fire safety design guidelines (e.g. Eurocodes), cannot describe with sufficient accuracy the characteristics of EVF under realistic fire conditions. In this context, a wide range of EVF correlations are comparatively assessed and evaluated. Quantification of their predictive capabilities is achieved by means of comparison with measurements obtained in 30 different large-scale compartment-façade fire experiments, covering a broad range of heat release rates (2.8 MW to 10.3 MW), ventilation factor values (2.6 m5/2 to 11.53 m5/2) and ventilation conditions (no forced draught, forced draught). A detailed analysis of the obtained results and the respective errors corroborates the fact that many correlations significantly under-predict critical physical parameters, thus resulting in reduced (non-conservative) fire safety levels. The effect of commonly used assumptions (e.g. EVF envelope shape or model parameters for convective and radiative heat transfer calculations) on the accuracy of the predicted values is determined, aiming to highlight the potential to improve the fire engineering design correlations currently available.
KW - Externally venting flames
KW - Fire plume
KW - Façade fire
KW - Large-scale fire tests
KW - Centreline temperature
KW - Heat flux
KW - Fire engineering design
KW - Flame height
KW - Flame width
KW - Flame projection
UR - http://link.springer.com/article/10.1007/s10694-016-0594-2
U2 - 10.1007/s10694-016-0594-2
DO - 10.1007/s10694-016-0594-2
M3 - Article
VL - 53
SP - 709
EP - 739
JO - Fire Technology
JF - Fire Technology
SN - 0015-2684
IS - 2
ER -