Piergiacomo Cancelliere
Italian National Fire Rescue and Service – CNVVF – Rome, Italy
Title: CFD analysis and experimental tests of a fire safety pressurized smokeproof enclosure
Biography
Biography: Piergiacomo Cancelliere
Abstract
Pressure differential systems have the purpose of maintaining tenable conditions in protected spaces for different types of building safe places like, escape routes, firefighting access routes, lobbies, stairwells and refuge areas. The aim of pressure differential systems is to establish airflow paths from protected spaces at high pressure to spaces at lower or ambient pressure, preventing the spread of toxic gas released during a fire. This strategy ought to be supported by a detailed design of the necessary air supply, considering also the cycle of opening and closing doors during the egress phase. The study deals with the design and experimental test of a simple pressure differential system intended to be used in a building as a pressurized smoke proof enclosure. Experimental tests are conducted in a simple 3 meter side cubic enclosure with two doors and no vent openings (Figure 1 and Figure 2). While a centrifugal fan blows constant airflow inside the structure, pressure trend in time is recorded during steady state and transient conditions; additionally, the velocity of the airflow across the doors has been measured by means of an anemometer. Numerical simulations are carried out to reproduce the same smoke proof enclosure configuration (both geometry and boundary conditions) using Fire Dynamics Simulator (FDS). Furthermore, specific attention is paid to the modelling of the leakage across the doors, directly inserted in the model through a localized HVAC (Heating and Venting Air Conditioning) advanced leakage function. Comparison between experimental tests and numerical simulations are provided. Once the model was correctly calibrated, other geometrical and mechanical configurations have been analyzed and studied, looking for more convenient and efficient positions of the fan to fulfil the requirements of pressure differential, airflow velocity and door handle force. This study highlights some fundamental aspects on the pressurization and depressurization during steady state and transient phases, trying to identify if there are airflow profiles typical of some geometrical configurations.
Figure 1: Pressurized fire safety smoke proof enclosure
Figure 2: Experimental fire safety smoke proof enclosure
Recent Publications
1. G Gai and P Cancelliere (2017) Design of a pressurized smoke proof enclosure: CFD analysis and experimental tests. Safety doi:10.3390/safety3020013.
2. P Cancelliere (2016) PV electrical plants fire risk assessment and mitigation according to the Italian national fire services guidelines. Fire and Materials 40(3):355–367.
3.P Cancelliere and C Liciotti (2016) Fire behaviour and performance of photovoltaic module backsheets. Fire Technology 52(2):333–348.