Chaque année en France, les feux de compartiments donnent lieu à plus de 88 000 interventions impliquant plus de 15 000 personnes dont plusieurs centaines de décès et de blessés graves. Aujourd’hui, lors de ces feux, les prises de décision et les délais d’intervention des équipes de secours sont principalement basés sur des décisions humaines, fruits de l'expérience. Une connaissance parfaite de la situation, de son évolution dans le temps et des dangers qui peuvent apparaître est impossible. C’est en partie la cause majeure des mauvais chiffres répertoriés ci-dessus. En effet, les processus physicochimiques qui régissent les feux de compartiments et les situations collatérales extrêmement réactives et dangereuses sont complexes. La transition entre un feu localisé et un feu généralisé peut prendre plusieurs formes. L'un des vecteurs les plus importants dans la propagation de la combustion pour les feux de compartiments sont les fumées, du fait de leur température élevée (souvent supérieure à 600°C) et des quantités importantes d’énergie, sous forme de chaleur, qu'elles contiennent. Malgré leur extrême dangerosité, les fumées restent importantes à étudier car elles véhiculent de précieuses informations, notamment sur l’apparition de phénomènes thermiques redoutés par les pompiers. Afin de mener cette étude, une cellule expérimentale composé de deux containers maritimes a été installée sur le site de formation incendie des sapeurs-pompiers de Seine-Maritime. Cette plateforme va permettre, grâce à un brûleur alimenté en propane, de produire des fumées chaudes dans uneconfiguration dite « feu réel ». Elles seront analysées en partie grâce à une technique de mesure non intrusive, la PIV. Les mesures par PIV grands champs seront comparées à des simulations LES de l’expérience (FDS). La double compétence (numérique / expérimentale) est essentielle dans ce type d’étude où les données expérimentales souffrent d’un manque de résolution (spatiale et temporelle) mais pour autant représentent des informations nécessaires à la validation des codes. / Each year in France, compartment fires result in more than 88,000 interventions involving more than 15,000 people, including several hundred deaths and serious injuries. Today, during fire compartments, the decision-making of the rescue teams is mainly based on human decisions, as a result of the accumulated experience. However, a perfect knowledge of the situation, its evolution over time and the dangers that may appear is impossible. Therefore, studying the fumes is of major interest. Indeed, smoke remains important to study because it conveys valuable information, especially on the appearance of thermal phenomena feared by firemen. In order to carry out this study, an experimental cell made up of two maritime containers was installed on the site of the Seine-Maritime fire brigade fire training. This platform will produce hot smokes in a configuration called "real fire" thanks to a propane burner. In this study, the smoke dynamics in a large scale experimental setup is analyzed using a non-intrusive measurement technique such as PIV (Particle Image Velocity). All the performed measurements are compared with LES (Large Eddy Simulation) simulations of the experiment using Fire Dynamics Simulator (FDS). The double expertise (numerical / experimental) is essential in this type of study where the experimental data suffer from a lack of resolution (spatial and temporal) but nevertheless represents an important source of information necessary for the validation of the codes.

This study is a presentation of an instantaneous and simultaneous velocity and concentration measurement technique and its applications on car park fire scenarios. <p>In this actual chapter 1 general introduction is given to each chapter. Chapter 2 is dedicated to a detailed description of the instantaneous and simultaneous velocity and concentration measurement technique and its associated error assessment methodology. The name of the new technique is derived from the names of the acquired parameters (VELocity and COncentration) and shall be hereafter referred to as VELCO. After having validated and performed an error assessment of this technique, it is applied to an investigation of full-scale car park (30 m x 30 m x 2.6 m – Gent / WFRGENT) fire cases in chapter 3. The measurements were carried out with the financial support of IWT-SBO program. In the full-scale measurements only the velocity part is applied of VELCO, yet it can be considered as its application since the special data treating was developed and implemented in the Rabon (see: §2.1.2) program, which is the software of the new technique along with Tucsok (see: §2.1.1) and they will be both discussed in the related chapter. Here it is enough to mention that the concentration and velocity information can be obtained independently as well. During the full-scale measurements, beyond of VELCO the smoke back-layering distances (SBL) are also derived from the temperature values, which were measured by thermocouples under the ceiling in the midline of the car park. The critical velocity, which is an important measure of fire safety, can be obtained from the SBL results. In chapter 4, isothermal fire modeling is surveyed in order to present how full-scale fires are modeled in small-scale. In this part of the study the theory of fire related formulae and an isothermal model are described. Here it is important to stress the fact that the fire modeling is not directly related to the VELCO technique. However it connects the full-scale to the small-scale measurements, which the technique is applied on. Chapter 5 discusses small-scale measurements (1:25 – Rhode Saint Genese / VKI) on the car park introduced in chapter 3 and their validation. After the validation, more complex car parks scenarios are also investigated due to the easy to change layout in the small-scale model with respect to the full-scale car park. In this chapter the smoke back-layering distances are obtained by VELCO. Finally, in chapter 6 important conclusions are drawn with the objective of increasing fire safety. <p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished