The Influence of Cavity Widths and Lateral Ventilation Conditions on the Fire Behaviour within a Non-Combustible Ventilated Façade System

Sammanfattning: Present uncertainties in key ventilation parameters, characterising the fire performance of facades, has necessitated clarification in the foundational understanding of the Fire Science Body of Knowledge. A test program conducted in collaboration between Lunds Universitet and the Kingspan Group, studied the influence of cavity widths and lateral ventilation conditions on the fire behaviour within Intermediate-scale ventilated façades following the ISO 13785-1 standards. Experimental works were performed in parallel to a Computational Fluid Dynamics analysis performed in the Fire Dynamics Simulator software. The thesis reports on the influence of domain discretization and complex geometric substitutions on the representativeness of simulated data. The experimental and simulated data were shown to hold reasonable correlation of information referring to the influence of lateral ventilation conditions on fire behaviour. Indicating the variable influence of obstructions and openings dependent on the point of interest and proximity within the sample. Data presented more critical conditions in near-field locations when closed ventilation conditions were applied, while far-field analysis indicated open conditions to be more critical. In the absence of a full experimental schedule, extension of studies was performed in the FDS software for later validation. Demonstrating the importance in selection of performance metrics in evaluating critical cavity widths. The data indicated more critical conditions present within the 50mm cavity sample, however greater flame heights were produced in the 25mm cavity.