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This paper is aimed at illustrating the capabilities of contemporary large eddy simulation (LES) solvers for compartment fire applications. Compartment fires refer to fires occurring indoors and feature a variety of complex phenomena associated with smoke accumulation and restricted air ventilation. The article provides a brief presentation of the main features of compartment fire dynamics followed by a review of the modelling challenges found in a LES treatment of these dominant features. The discussion shows that in addition to a suitable model for the turbulent flow dynamics, simulations of compartment fires require a collection of physical sub-models in order to describe a large range of multi-physics phenomena, including pyrolysis processes, buoyancy-driven flow, combustion, soot formation and thermal radiation. Some examples of LES simulations of compartment fires are also presented, using two different solvers that represent the current state-of-the-art of compartment fire modelling: FDS developed by the National Institute of Standards and Technology, USA, and FireFOAM developed by FM Global, USA. Both solvers are available as free open-source software and are representative of ongoing efforts within the fire research and engineering community to self-organise and to promote the general area of LES-based fire modelling. [ABSTRACT FROM AUTHOR]

Abstract: The general objective of this research is to adapt current combustion modeling capabilities used in computational fluid dynamics solvers to the treatment of under-ventilated compartment fires. More specifically, we consider in the present study two models proposed to describe: diffusion flame extinction due to air vitiation; and the emission of carbon monoxide (CO) and unburnt hydrocarbon (HC) mass in a compartment fire. The flame extinction model is based on a flammability diagram parametrized in terms of vitiated air properties. The CO/HC mass model is based on: a transport equation for fuel mass; a comparison of this fuel mass to a Burke–Schumann chemical-equilibrium expression; and an interpretation of the difference as a measure of incomplete combustion. Both models are implemented into a large eddy simulation solver developed by the National Institute of Standards and Technology, USA. The models performance is tested via detailed comparisons with an experimental database corresponding to reduced-scale compartment fires. The study considers two cases that correspond to different values of the fire room global equivalence ratio and are representative of strikingly different flame behaviors. The comparative tests serve to evaluate the general ability of the models to describe the transition from extinction-free conditions to conditions in which the flame experiences partial or total quenching, as well as the transition from fire regimes with no or little CO emission to regimes that emit hazardous levels. [Copyright &y& Elsevier]