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This publication presents the experimental and numerical methods to model the devolatilization process of a glass‐fibre‐reinforced polyester/balsa‐cored sandwich material on small scale. The fundamental modelling of the source term in pyrolysis‐based fire simulations requires as input data the thermochemical properties of solid fuel and the kinetic parameters of the devolatilization process. First, the thermal decomposition of both elements composing the sandwich structure was studied by thermogravimetry coupled with gas analysis, in air and pure nitrogen atmospheres at several heating rates, in order to define a comprehensive multi‐step reaction pathway. A differential equation system is defined to model these decomposition processes. The kinetic parameters were then estimated by solving the system of equations by an inverse problem. Second, the fire behaviour of each element was studied separately and then combined in the sandwich structure on the cone calorimeter. In addition, numerical simulations with Fire Dynamics Simulator were performed to gradually assess the ability of the model(s) to reproduce each element composing the sandwich structure. Numerical and experimental results are compared and then discussed. Overall, the model provides a good agreement with the experimental data and encourages to model higher scales. Copyright © 2012 John Wiley & Sons, Ltd.

Summary Thanks to their thermal insulation properties, rigid polyisocyanurate foams are commonly used in the modern built environment, as well as in transportation and industrial applications. However, the fire behaviour of this kind of foam remains one of the most limiting factors for their wider use as insulation material in some sectors. Indeed, this type of material is thermally and chemically reactive. The general scope of this study is to investigate the effects of a reduced oxygen atmosphere on the reaction to fire of flame‐retardant polyisocyanurate foam. This paper reports the results of an experimental campaign, which was performed using a controlled‐atmosphere cone calorimeter, coupled to a Fourier transform infrared spectrophotometer. The dependence of the results on both oxygen concentration and irradiance level is presented and discussed. The chemical compositions of the identified gaseous products were qualified and quantified during both the decomposition and the combustion processes. Copyright © 2016 John Wiley & Sons, Ltd.

Le travail présenté dans ce document s'inscrit dans le cadre d'un projet de recherche français de 3 ans dédiéà l'utilisation de matériaux composites dans la construction navale. Dans ce projet, il est prévu d'utiliser le code CFD FDS-5 avec un modèle de pyrolyse pour tenir compte de la contribution de cloisons en matériau composite sur le développement du feu, dans le cadre de la simulation de scénarios incendies a bord d'un navire. Pour garantir la qualité de ces simulations, une méthode de validation progressive des modèles utilisés aété suivie. Cette méthode est basée sur une approche combinée expérience-simulatioǹ aéchelle croissante. Pour illustrer la démarche, on présente ici les résultats d'uneétude expérimentale du comportement au feu d'unéchantillon de matériau composite, sur un banc d'essaisà petiteéchelle, puis la simulation des essais correspondants.