Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Fire spread; FDS. Includes bibliographical references (leaves 38-41).

Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Office buildings; Steel beams; Lumped parameter method; Cardington Tests; Design fire curves . Includes bibliographical references (leaves 144-146).

Thesis (M.A.)--Washington State University, May 2007. / Includes bibliographical references (p. 72-79).

Pollination networks summarize interactions between plants and pollinators, providing insight into ecosystem stability. An unplanned fire provided the opportunity to assess network structure following disturbance in the Tall Grass Prairie Preserve in southern Manitoba. I established transects in sites burned <1 year, 5-6 years, or 10+ years ago. I assessed species richness, diversity, abundance, and phenology of insects and flowering plants. I created interaction matrices by recording plant-insect interactions, and sampled pollen loads from insects. Network structure was assessed by connectance, nestedness, and interaction strength. Flowers were more abundant and bloomed two weeks earlier in newly burned sites in 2010. Bees showed responses to fire based on nesting habitat, however visits by syrphids were related to precipitation. Network structure showed that tall grass prairie pollination networks were resilient to disturbance and variable environmental conditions, and management of prairie by fire did not negatively impact plant-pollinator interactions within the community overall. / February 2016

Fire development in a vented enclosure can proceed in an explosive and disastrous manner called flashover. This thesis examines when, why and how flashover occurs and gives the answers in terms of a few determining dimensionless parameters. The mechanism of flashover considered in this thesis is an enhancement of the burning rate because of thermal radiation from a layer of hot smoke, produced in the course of the fire, to the fire bed. A model, which is proposed for the problem, describes the development fro~ the moment of ignition incorporating the traditional two-zone approach. During early fIre development the density and temperature of the lower zone are reasonably assumed to be close to their initial value. Flashover itself is assumed to occur early in the fIre development, within the fuel controlled combustion regime. The model is analysed using the techniques of classical thermal explosion theory. Explicit criteria are found analytically and graphically to determine if the fIre will achieve flashover or not. The temperature-time characteristics of the fIre development are obtained explicitly for the fIrst time. It is shown that the thermal inertia of the compartment walls can have a significant effect upon the development. The effect of geometrically scaling the compartment is considered. Nondimensional analysis makes such study effective and leads to a square root relationship for the temperature/time characteristics of the fire development. The correlation between the model, four prevIOUS models and small scale experiments is examined. Under reasonable assumptions all models are shown to be described by the same mathematical problem. This means that the criterion for flashover and the development characteristics can be used for any of the modified models observed. Results are illustrated for an experimental fire box used in many experiments.

The use of small scale facilities in experimental fire research studies is well estabhshed. This thesis concerns the use of small scale facilities to examine principally the influence of thermal inertia of the lining material on ventilated enclosure fire The radiation error of the thermocouple reading was studied using radiation network models. Previous theoretical studies were implemented to provide improved models appropriate to the more complex arrangements considered here. Modeling was used to assess the radiation error of different sizes of thermocouple in the hot layer measuring position for post and pre flashover fires, and the models were compared with experiment. The current range of thermal inertia values for building products is much wider than those used in the regression by which the classical theory of pre-flashover temperature was derived (McCaffery et al. 1981). The range considered here is greater then has previously been considered by systematic experimental testing whilst maintaining all other independent key variables constant. Using of reasonable assumptions, the mass loss rates of non-flashover and flashover conditions were predicted by numerical calculation integrated with a zone model. Successful prediction was also made for published tests where sufficient information was available, and good agreement was found irrespective of flashover, scale or geometry. Two important and necessary assumptions used in the zone model, concerning specifically radiation heat transfer in the flashover condition are: that an average temperature of hot gas and flashover flame may be represented by a single thermocouple measurement; and that the massive increase in production of flanu-nable vapours from the fuel surface during flashover leads to a "cool core" partial scattering or blocking of the incident radiant heat from the flashover flame and hot gas. A computer programme was developed to implement and test recent flashover theory (Graharn et al. 1995). A logarithinic relationship has here been suggested between the thermal inertia parameter ', 8' and thermal inertia value of lining material. That relationship matches the current experimental results and other published data. The occurrence of flashover and the value of hot gas peak or steady temperature can be predicted using the computer programme, based on the published theory.

Complex computer models, built on basic physical principles, have the potential to aid in the understanding and prediction of wildland fire behavior. However, there remain significant uncertainties and assumptions in the way such models describe the fire, the vegetation, and the interaction of the two. To understand a model’s capabilities, limitations, and the improvements which are still necessary, comparison of model predictions to experimental measurement is critical. Unfortunately, collecting such measurements is particularly difficult at the large scale over which real wildland fires occur and, as a result, this happens infrequently. To address this, an opportunity was seized to collect a detailed set of measurements of fire behavior in a real forest environment. These measurements are thoroughly analyzed for the description they provide of the fire behavior. They are then used as a benchmark to test the capabilities of a particular complex model to describe such a fire and to highlight the limitations and uncertainties. As a result of this evaluation, a set of recommendations for future research, both in experiments and modeling, are offered, in order provide a coherent strategy for the future which will significantly advance these models.

Intumescent coatings are used in the field of fire protection to prevent certain construction elements reaching the critical temperatures at which excessive damage would. occur, thus avoiding premature structural collapse. The studies presented in this thesis have been directed towards an understanding of intumeseent coatings and the process of intumescence. The kinetics and mechanism of intumeseence are discussed. The behaviour of the raw materials used in the preparation of intumeseent coatings, was studied at elevated temperatures using thermal analytical techniques, and new formulations were developed. These formulations were examined In the laboratory using various screening tests and were also subjected to a large scale hydrocarbon fire test alongside other commercially-avallable coatings. A simplified coating formulation with the minimum of ingredients required to produce good intumescent properties was developed. This formulation was subjected to various heat-radiation intensities using an ISO ignitablilty apparatus. The behaviour of the intumescence, process observed was explained by a simple theoretical model. The model of Buckmasterv Anderson and Nachman was used and several new results were derived. In particular a relationship was derived giving the time taken for the temperature at the inner surface of the coating to reach a given value. The durability of the newly-developed intumescent coatings, and methods of improving it, were also investigated.

This work has investigated the possibility of developing a model, capable of being used to harmonise standards of fire cover within the EU. The model had to take into account social, humanitarian, economic and environmental factors and the built environment in determining an appropriate emergency response by fire brigades to rescues, fires and contamination of land, air and watercourses. The resulting standards had to be socially acceptable and economically defensible. After examining existing standards of fire cover and the means of determining those standards, all current research into standards of fire cover and related issues was reviewed. A study was also undertaken into fire science, the means of predicting frequency of fire and the means of limiting the incidence and size of fires. Economics, as applied to local and national government and as applied to fire safety systems and fire services was explored. From that initial research it was concluded that the fundamental concepts of fire cover had remained unchanged since the restructuring of fire brigades throughout Europe during the late 1940's and had no relevance to the modern built environment. While some aspects of existing policies and some elements of current research were of value, this work has developed new concepts, including. • Functional requirements for common fire and non-fire emergencies. • Entry preparation time based on the criteria, "The time at which fire fighting shall commence." • Limiting fire size in buildings to "As Small As Reasonably Practicable for a Set Duration" for property protection. • Quantifying the term "As Small As Reasonably Practicable". • Defining a Standard Predetermined Attendance (SPDA) for all incidents. • Determining optimum attendance time limits dependent on the frequency of calls and the installed fire protection features in buildings. • A method of calculating an economic base for determining critical call numbers. • A means of establishing the optimum location of fire stations within a given area. • The number of SPDA's required at each fire station related to total workload. • The provision of assistance to areas that are outside maximum attendance times. The economic model that has resulted, accurately includes all of the potential economic, social, and political variations as the basis of calculation of Standards of Fire Cover in individual Member States of the European Union. It is the contention of this thesis that it is possible to construct formulae, based on sound economic principals, which are capable of being applied to the different fiscal situation in different countries, thereby ensuring similar relative standards.

Pour des raisons d'économie d'énergie, les façades des bâtiments deviennent de plus en plus sophistiquées à la fois par leurs configurations et leurs compositions. Mais la quantité de combustible de ces nouvelles façades est bien supérieure à celle des façades traditionnelles. Par conséquent, le risque de propagation du feu via la façade est plus important. Ainsi, l'objectif de ce travail est de modéliser le développement du feu à l'intérieur et à l'extérieur d'un bâtiment en prenant en compte différentes configurations et compositions de façade. Cette recherche expérimentale et numérique a permis d'identifier les paramètres qui augmentent ou diminuent le risque de propagation du feu via une façade. Dans un premier temps, après avoir vérifié la capacité du code de calcul à modéliser les flammes pariétales, une étude numérique qui étudie l’influence de la géométrie d’une façade sur la propagation du feu via la façade a été réalisée. En effet, les différents phénomènes liés aux dimensions des ouvertures et/ou à la configuration de la façade ont été identifiés. Il a donc été possible d’analyser leur influence sur le risque de propagation du feu en façade à travers des grandeurs telles que la puissance libérée à l’extérieur du bâtiment ou encore la hauteur de flamme et les actions thermiques engendrées. Parmi les configurations étudiées figurent des géométries plus ou moins complexes pouvant être rencontrées sur les bâtiments. Par exemple, les ouvertures multiples ou encore des configurations en « U » afin d’étudier l’influence de l’effet cheminée sur l’extension des flammes. En effet, ce type de configurations a déjà été la cause d’une propagation rapide d'incendies via des façades quelles que soient leurs compositions. Par la suite, une étude expérimentale sur la propagation du feu sur une paroi combustible a été réalisée avec deux objectifs. Tout d’abord afin d’étudier les phénomènes de propagation sur une façade combustible (température de flamme, hauteur de propagation, contribution énergétique de la façade), mais également pour récolter des données expérimentales permettant la validation de modèles de propagation et les simulations numériques dans cette situation. Dans un deuxième temps, une nouvelle campagne expérimentale a permis d’étudier l’influence de la présence d’une lame d’air de ventilation entre le bardage et le mur sur la propagation du feu. Cette dernière configuration est largement utilisée dans la construction des façades comportant généralement une couche d’isolation dans la lame d’air. Cette recherche, à la fois académique et applicative, a permis de fournir des informations originales sur le développement et le comportement du feu le long d’une façade, qu’elle soit combustible ou non. Les résultats numériques présentés mettent en évidence les différents paramètres gouvernant le développement d’un feu le long d’une façade, ce qui facilite la compréhension des phénomènes liés à cette problématique. De plus, les différents essais réalisés pourront servir de base de données à la modélisation de la propagation d’un incendie le long d’une paroi combustible, ainsi qu’à la mise au point des modèles de développement et de propagation. / In order to enhance the energy efficiency of buildings, the facades are becoming more sophisticated in both their configurations and compositions. However, the amount of fuel of these new facades is much higher than that of traditional facades. Therefore, the risk of fire spread through the facade is more important. Thus, the objective of this work is to model the fire development inside and outside of a building, taking into account different configurations and facade compositions. This experimental and numerical research has identified the parameters that increase or decrease the risk of fire spread via the façade. First, after verifying the capacity of the FDS code to model the parietal flames, a numerical study that examines the influence of the geometry of a facade fire spread was completed. Indeed, the various phenomena related to openings dimensions and / or configurations of the façade have been identified. It was therefore possible to analyze their influence on the risk of fire spread along the façade using quantities such as the heat released outside the building, the flame height and thermal actions (temperature, fluxes). Among the configurations studied are contained more or less complex geometries that can be encountered on the buildings. For example, multiple openings or "U" configurations were investigated in order to study the influence of the chimney effect on the extension of flames. Indeed, this type of configuration has already been the cause of the rapid spread fire through walls regardless of their compositions. Subsequently, an experimental study on fire spread along a combustible wall was realized with two goals. First, a series of tests was performed in order to observe propagation phenomena on a combustible façade and to collect experimental data to validate propagation models and numerical simulations in this situation. Secondly, another experimental campaign was used to study the influence of the presence of a ventilation air gap between the cladding and the wall on the spread of fire. This latter is widely used in the construction of facades. This research, both academic and applicative, has provided new information on the fire development and fire behavior along a façade, combustible or not. The numerical results demonstrate the various parameters governing the development of a fire along a façade, which facilitates the understanding of phenomena related to this issue. In addition, various tests can be used as a database for the modeling of fire spread along a combustible wall. Thus, this work contributes to the development of models of fire development and spread on buildings via the façade.