Thermo-Fluid Dynamics Analysis of Fire Smoke Dispersion and Control Strategy in Buildings

Abstract

Smoke is the main threat of death in fires. For this reason, it becomes extremely important to understand the dispersion of this pollutant and to verify the influence of different control systems on its spread through buildings, in order to avoid or minimize its effects on living beings. Thus, this work aims to perform thermo-fluid dynamic study of smoke dispersion in a closed environment. All numerical analysis was performed using the Fire Dynamics Simulator (FDS) software. Different simulations were carried out to evaluate the influence of the exhaust system (natural or mechanical), the heat release rate (HRR), ventilation and the smoke curtain in the pollutant dispersion. Results of the smoke layer interface height, temperature profile, average exhaust volumetric flow rate, pressure and velocity distribution are presented and discussed. The results indicate that an increase in the natural exhaust area increases the smoke layer interface height, only for the well-ventilated compartment (open windows); an increase in the HRR accelerates the downward vertical displacement of the smoke layer and that the 3 m smoke curtain is efficient in exhausting smoke, only in the case of poorly ventilated compartments (i.e., with closed windows).

Procedures and Methodologies for the Control and Improvement of Energy-Environmental Quality in Construction

“…In [6], Battisti investigates the thermal comfort in open spaces around existing buildings in Rome and the possible improvement thanks to cool materials, greenery and permeable green surfaces. Computational Fluid Dynamics techniques are used in [7] by Gomez et al to study the fire smoke behavior in an enclosed space, and they present an easy tool to support the design of smoke control systems.…”

Effects of Time to Unactuate Air Conditioning on Fire Growth

“…Whether the fire growth is enhanced or suppressed depends on which factor plays the main role. To further understand fire growth in confined spaces affected by ventilation, many previous studies have investigated the heat release rate (HRR) of fire sources [18][19][20][21][22][23][24][25], the fuel mass loss rate [19,[26][27][28], the burning rate [13,17,29], the temperature [13,18,22,23,25,[28][29][30][31][32] and visibility [30,32] of the confined space, the thickness of the hot smoke layer [19,25,27,31], the heat fluxes on the floor [28] and the time to flashover (t fo ) [18,32]. A complete description of these studies can be found in Wang and Tsai [32].…”

“…The effects of both natural and mechanical ventilation on fire growth must be addressed. [22] 3 × 3.6 × 2.3M erci and Maele [23] 3 × 3.6 × 2.3Ľ assus et al [24] 2 × 2 × 2Ǧ omez et al [25] 32 × 17 × 8ˇŤ homas and Bennetts [26] 1.5 × 0.6 × 0.3P ierce and Moss [27] 1.8 × 1.2 × 1.2Ť ofilo et al [28] 1.2 × 0.8 × 0.8Ǩ umar and Naveen [29] 2.79 × 2.24 × 1.62Ȟ uang et al [30] 22.5 × 16 × 12Š u et al [31] 2.3 ×1.3 × 2.5ˇW ang and Tsai [32] 3.8 × 3.8 × 2.4ˇŠ u et al [31] utilized the Fire Dynamics Simulator (FDS) to analyze the position of air inlet and air exhaust in small vestibules of high-rise buildings. In their fire simulation scenario, the front door and rear door of the confined space were open, and the smoke exhaust and air supply rates were both 4.0 m 3 /s in the confined space.…”

Experimental and simulation study of the interaction characteristics of nano‐MgO and smoke in the fire of a ship engine room

“…At present, natural ventilation, mechanical ventilation, and water mist are conventional methods for controlling smoke movement. The smoke can be moved outside the confined space by the way of natural and mechanical exhaust because the density of smoke is smaller than that of air and it is driven by thermal, which has been confirmed by Lu, 6 Safarzadeh, 7 Tao, 8 and Gomez 9 . However, natural ventilation and mechanical ventilation are obviously contradictory to the commonly used fire extinguishing methods in enclosed cabins.…”