Experimental study on the heat flux profile upon the building facade of the window-ejected fire plume

Abstract

The window-ejected fire plume with the excess fuel released outside the opening poses great threat to the building facade due to the hazardous heat flux. This paper investigates experimentally the temperature inside the compartment, convective- and excess- heat release rate, facade flame height and the heat flux profile upon the building facade of the under-ventilated window-ejected fire plume. A set of experiments are carried out with a compartment-facade model consisting of a 0.40 m reduced cubic compartment and a vertical facade. An opening with various sizes is set at the center of the sidewall of the compartment. The temperature inside the compartment, convective- and excess- heat release rate, facade flame height and the heat flux profile upon the building facade are measured and quantified by thermocouples, camera and heat flux gauge array upon the building facade of the under-ventilated window-ejected fire plume for various openings and heat release rates. The center line heat flux could be correlated well with the non-dimensional height normalized by the flame height involving the correction factor. A global model on the heat flux profile upon the building facade incorporating the aspect ratio of the opening, flame height and the convective heat release rate, is developed to describe the transverse heat flux evolution in a general dimensionless form, and the proposed model correlates the experimental data well. The obtained experimental data and proposed model provide a basic understanding of the heat/thermal impact on the facade of the window-ejected fire plume due to excess fuel diffusion combustion.