Experimental study on transverse temperature profile of spill plume and thermal characteristic difference with lateral direction

Abstract

The present research investigated theoretically and experimentally the transverse temperature profiles of spill buoyant plume ejected from a fire compartment, as well as the thermal characteristic difference between the transverse and lateral direction. The previous literatures only focused on the vertical and lateral (normal to facade) temperature profiles; although the transverse (parallel to facade) temperature profiles will also have a significant impact on the thermal expansion, and it could be essentially different from the lateral temperature profile due to the existence of facade (air entrainment restricted), however, this topic has not been revealed yet. Hence, in present study, the plume thickness of transverse direction was theoretically analyzed, and a model for transverse temperature profile using the Gaussian function was established using the new effective plume thickness. Experiments were then conducted by using a reduced-scaled fire compartment with one opening attached on the facade wall. The transverse and lateral temperature profile of the spill fire plume along the facade wall were measured and analyzed. The model for transverse temperature profile can be well verified by obtained data. And it is found that the transverse temperature decay slower than the lateral temperature due to the Coanda effect caused by the one-side air entrainment. The obtained experimental data and proposed transverse temperature profile function in this work provide a basic understanding for the thermal characteristics of spill buoyant plume ejected from a fire compartment, and the proposed function can be applied to predict the spread possibility of building facade fire.