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This report presents both small scale laboratory tests and tunnel fire tests carried out in a FORMAS project. Four series of small scale laboratory tests were conducted to obtain the material properties, burning properties, water spray distributions, and spray droplet size distributions. The main efforts were, by adopting the Froude scaling, seven series of tests conducted in a about 50 m long container tunnel with a scale of 1 to 3. This report presents results on the influence of low pressure, medium pressure and high pressure water-based fixed fire fighting systems (FFFSs) on fire development, fire spread to adjacent vehicles, structural protection, tenability, smoke control, spray deflection and spray resistances. The focus is to compare the performance of three default FFFSs and to evaluate the efficiency of each of the FFFS. The results show that the default low pressure FFFS performs well in term of suppressing the fire development, preventing the fire spread to nearby vehicles, providing tenable conditions for evacuation and rescue service, protecting tunnel structure and easing the problem with spray deflection due to tunnel ventilation. The default high pressure FFFS is usually on the opposite side while the default medium pressure FFFS usually lie in between.

Building codes around the globe dictate the design and construction of buildings. For most buildings, designers will follow prescriptive code provisions to demonstrate code compliance. However, some buidling codes allow the use of performance-based design to demonstrate code compliance. Performance-based design is usually more complex but allows for greater flexibility in the use of materials and systems. Regardless of the code compliance methods, the combustibility of timber structures and wood products needs to be well understood and properly accounted for in building designs. This paper describes the develpment of a new international guidance document on fire safety in timber building within the Fire Safe Use of Wood (FSUW) network, written by 13 lead authors assisted by more than 20 experts in over a dozen different countries.

Som en följd av global uppvärmning blir det allt viktigare med resiliens mot klimatkrisens konsekvenser, däribland mer frekventa skogsbränder. Då våtmarker kan behålla vatten och ge resiliens mot torka och bränder är det intressant att undersöka relationen mellan våtmarker och skogsbränder. Syftet med detta arbete är att undersöka våtmarkers påverkan på skogsbränder i boreala skogsmiljöer, där frågeställningarna berör antändningsrisk, intensitet, brandskador, areell spridning och utdikning. Arbetet genomförs som litteraturstudie och GIS-analys med fokus på brandspridning. I GIS genomfördes först en multikriterieanalys och sedan en modellering av brandförlopp, i två områden i Hälsingland. Enligt analys och tolkning av resultat är fuktighet, grundvattennivå, vegetation, ytstruktur och storlek de viktigaste faktorerna i våtmarkers relation till skogsbränder. Sannolikhet för antändning, brandintensitet och brandskador minskar alla med ökad fuktighet, ökad grundvattennivå, gott om vitmossa och mindre av annan vegetation. Dessa faktorer gör även våtmarker till bättre brandbarriärer, speciellt i kombination med ökad storlek och heterogen ytstruktur. I motsats är våtmarker med lägre fuktighet och grundvattennivå, större bränsletillgång och träd sämre som barriärer mot skogsbrand och upplever intensivare bränder. Under extrem torka riskerar dock alla våtmarker, i olika utsträckning, att torka ut till den grad att bränder sprider sig över dem.GIS-analysen visar en koppling mellan sankmarker och områden med långsam brandspridning under normala förhållanden, och en stor lokal variation i förutsättningarna för brandspridning. Utdikning av våtmarker försämrar våtmarkernas resiliens mot skogsbränder, och skapar en risk för torvbränder, med allvarliga konsekvenser. En återvätning av utdikade våtmarker skulle förbättra deras brandresiliens., As a result of global warming, it is ever more important with resilience towards the consequences of the climate crisis, including more frequent wildfires. Since wetlands can retain water and give resilience towards drought and fires, it is interesting to explore the relation between wetlands and wildfires. This study aims to research the influence of wetlands on wildfires in boreal forest environments, with research questions regarding risk of ignition, fire intensity, fire damage severity, areal spread and wetland drainage. The work consists of a literature review and GIS analysis focusing on fire spread. The GIS analysis is done through a multi-criteria analysis and afterwards a modeling of fire development, in two areas in Hälsingland, Sweden. According to analysis and interpretation of the result, the most important factors in the relation between wetlands and wildfires are moisture, water table level, vegetation, surface structure and wetland size. Probability of ignition, fire intensity and fire damage are all reduced with increased moisture, higher water table, plenty of sphagnum moss and less other vegetation. These factors also improve wetland efficiency as barriers against fire, especially in combination with increased size and a heterogeneous surface structure. On the contrary, wetlands with a lower moisture level and water table, larger fuel availability and trees function less efficiently as fire barriers and experience more intense fires. During extreme drought, however, all wetlands to a different extent risk drying out to the point where fire can spread over them. The GIS analysis displays a connection between fens and areas with slow fire propagation under normal conditions, as well as a large local variation in the factors influencing wildfire propagation. Wetland drainage deteriorates wetland resilience against wildfires, and creates a risk of peat fires, with severe consequences. Rewetting of drained wetlands would improve their fire resilience.

The number of fire incidents are increasing, especially for large vessels. Indications are that the fire extinguishing and fire detection systems have not kept up with the vessel’s enlargements. Therefore, knowledge of the fire-spreading mechanism between containers is one of many essential parts in increasing fire safety aboard container ships.

The large and catastrophic wildfires have been increasing across the globe in the recent decade, highlighting the importance of simulating and forecasting fire dynamics in near real-time. This is extremely challenging due to the complexities of physical models and geographical features. Running physics-based simulations for large wildfire events in near real-time are computationally expensive, if not infeasible. In this work, we develop and test a novel data-model integration scheme for fire progression forecasting, that combines Reduced-order modelling, recurrent neural networks (Long-Short-Term Memory), data assimilation, and error covariance tuning. The Reduced-order modelling and the machine learning surrogate model ensure the efficiency of the proposed approach while the data assimilation enables the system to adjust the simulation with observations. We applied this algorithm to simulate and forecast three recent large wildfire events in California from 2017 to 2020. The deep-learning-based surrogate model runs around 1000 times faster than the Cellular Automata simulation which is used to generate training data-sets. The daily fire perimeters derived from satellite observation are used as observation data in Latent Assimilation to adjust the fire forecasting in near real-time. An error covariance tuning algorithm is also performed in the reduced space to estimate prior simulation and observation errors. The evolution of the averaged relative root mean square error (R-RMSE) shows that data assimilation and covariance tuning reduce the RMSE by about 50% and considerably improves the forecasting accuracy. As a first attempt at a reduced order wildfire spread forecasting, our exploratory work showed the potential of data-driven machine learning models to speed up fire forecasting for various applications.

[ES] Debido a que las catedrales góticas trabajan distribuyendo de una manera muy característica las cargas a través de los diferentes elementos que la conforman, este TFM se enfoca en estudiar las variaciones en la respuesta estructural frente a peso propio y frente a cargas horizontales en la catedral de Notre-Dame de París con las diferentes tipologías propuestas para la nueva cubierta. Así, será posible estudiar la idoneidad de la nueva cubierta teniendo en cuenta un punto de vista esencial y que, sin embargo, queda muchas veces en segundo plano: el de la respuesta estructural, ligado con la eficiencia en la forma de trabajar de los elementos y los materiales. Tanto la cubierta como algunos tramos de bóveda que quedaron destruidos después del incendio contribuían especialmente a la redistribución de esfuerzos y rigidizaban la estructura en cuanto a las acciones horizontales. Además, las diferentes tipologías propuestas para la nueva cubierta parecen, a priori, proporcionar una redistribución de esfuerzos y una rigidez horizontal diferente (cubierta plana, cubierta a dos aguas reconstruyendo las bóvedas y cubierta a dos aguas manteniendo la bóveda sin la plementería). Se propone el estudio de la respuesta estructural de la catedral frente a peso propio y frente a acciones horizontales para los siguientes estados: catedral previa al incendio, posterior al incendio sin haber tomado medidas de rehabilitación y, finalmente, con las distintas tipologías de cubierta. Se ha considerado analizar la respuesta estructural desde un punto de vista global sin entrar en detalles geométricos o de elementos particulares, debido a que las asunciones de cálculo elástico lineal no serán adecuadas para el estudio de elementos específicos de la mampostería., [EN] Owing to the fact that gothic cathedrals distribute loads in a very characteristic way through the different elements that make it up, this TFM focuses on studying the variations in the structural response under self-weight and horizontal loads in Notre-Dame cathedral from Paris with the different typologies proposed for the new roof. Thus, it will be possible to study the suitability of the new roof taking into account an essential point of view that, however, often remains in the background: the structural response, linked to the efficiency in the way that elements and materials work. Both the roof and some sections of the vault that were destroyed after the fire especially contributed to the redistribution of forces and stiffened the structure in terms of horizontal loads. In addition, the different typologies proposed for the new roof seem, a priori, to provide a redistribution of forces and a different horizontal stiffnes (flat roof, gable roof rebuilding the vaults and gable roof keeping the vault without rowlock). The study of the structural response of the cathedral under self-weight and horizontal loads for the following states is proposed: cathedral before the fire, after the fire without having taken any rehabilitation measures and, finally, with the different roof typologies. It has been considered to analyze the structural response from a global point of view without going into geometric details or particular elements, since the assumptions of linear elastic calculation will not be adequate for the study of specific elements of the masonry.

Recent extreme wildfire seasons in several regions have been associated with exceptionally hot, dry conditions, made more probable by climate change. Much research has focused on extreme fire weather and its drivers, but natural wildfire regimes—and their interactions with human activities—are far from being comprehensively understood. There is a lack of clarity about the 'causes' of wildfire, and about how ecosystems could be managed for the co-existence of wildfire and people. We present evidence supporting an ecosystem-centred framework for improved understanding and modelling of wildfire. Wildfire has a long geological history and is a pervasive natural process in contemporary plant communities. In some biomes, wildfire would be more frequent without human settlement; in others they would be unchanged or less frequent. A world without fire would have greater forest cover, especially in present-day savannas. Many species would be missing, because fire regimes have co-evolved with plant traits that resist, adapt to or promote wildfire. Certain plant traits are favoured by different fire frequencies, and may be missing in ecosystems that are normally fire-free. For example, post-fire resprouting is more common among woody plants in high-frequency fire regimes than where fire is infrequent. The impact of habitat fragmentation on wildfire crucially depends on whether the ecosystem is fire-adapted. In normally fire-free ecosystems, fragmentation facilitates wildfire starts and is detrimental to biodiversity. In fire-adapted ecosystems, fragmentation inhibits fires from spreading and fire suppression is detrimental to biodiversity. This interpretation explains observed, counterintuitive patterns of spatial correlation between wildfire and potential ignition sources. Lightning correlates positively with burnt area only in open ecosystems with frequent fire. Human population correlates positively with burnt area only in densely forested regions. Models for vegetation-fir

Heat and mass transfer are important processes associated with wildland fire. Both radiant and convective heat transfer are important processes with convection often being the dominant mechanism. Unlike radiation, there is no direct method of measuring convection. Since convective heat transfer is governed by the fluid flow, understanding the fluid flow provides good understanding on the convective heat transfer. In fluid mechanics, flow visualization is a common methodology used to understand flow characteristics. Schlieren imagery is a common flow visualization technique which captures changes in fluid density such as the ones occur around a fire. Background-Oriented Schlieren (BOS) is a flow visualization technique that uses a background image with various patterns to visualize the density gradient caused by density fluctuations in a fluid. We applied BOS to measure the flow associated with laboratory-scale line fires. The reproducible fires were spreading in pine needle fuel beds in a wind tunnel with and without imposed wind. This initial application of BOS in a fire environment successfully visualized the flow around the flame. The visualized flow underwent a secondary process to produce the velocity field of the flow. Results indicate that even in conditions where the fire is known to be dominated by radiation, wind carried the thermal plume ahead of the flame front and expanded the thermal plume. In contrast, in the no wind condition, the thermal plume remained vertical above the fire. Using the BOS imagery, a new model for estimation of convective heat transfer was introduced. In addition to estimation of the convective heat transfer ahead of the fire, this new model enables visualization of convective motion.

[ES] En pleno siglo XXI, a pesar de los avances exponenciales en ciencia e investigación, aún existen fenómenos naturales que el ser humano no ha llegado a comprender. Uno de ellos es el comportamiento explosivo del fuego en incendios forestales. Este comportamiento es muy similar al que pueden tenerlos ya estudiados “backdraft” y “flashover”, y que ocurren en incendios de interior. Según diversos estudios, cuando se dan determinadas condiciones en el medio natural (tanto climáticas, topográficas, modelo de combustible vegetal, etcétera), un frente de fuego puede llegar a avanzar a más de 120 kilómetros por hora. Son muchos los casos y testimonios, varios de ellos expuestos en este trabajo, los que evidencian la existencia de este tipo de fenómeno. Lamentablemente, tras él se esconde un número alarmante de víctimas mortales ya que este avance tan rápido y repentino de las llamas suele sorprender a los equipos de extinción. Son varias las corrientes de investigación que tratan de sentar bases en un tema tan delicado como este, pero sin llegar a las mismas conclusiones. Existen contradicciones entre las diferentes teorías, y la ciencia oficial está lejos de llegar a un consenso.Por tanto, en el presente estudio se analizan los procesos que rigen el desarrollo de estos fenómenos deflagrantes, en base a las corrientes de investigación existentes y a diversos sucesos reales que se han documentado. Mediante el análisis de esta información se pretende llegar a una conclusión propia acerca del fenómeno, además de establecer mecanismos de prevención. Es evidente que estos sucesos no pueden ser erradicados, pero sí mitigar sus consecuencias y tratar de establecer las condiciones en las que ocurren para poder detectarlos a tiempo., [EN] In the 21st century, despite all exponential advances in science and research, there are still natural phenomen that human beings have not come to understand. On of them is the explosive behavour of fire in wildfire. This behaviour is very similar to those already studied backdraft and flashover, that occur in indoor fires and which the activity teams are very prepared. According to some studies and researches, when there are critical conditions (both climatic conditions, topography, fuel modelo f vegetation, etc.) a fire front can reach more than 120 kilometers per hour. There are many cases and testimonies, some of them exposed in this research, which shows the existence of this type of phenomenon. Unfortunately, behind him hides an alarming number of fatalities due to this rapid rate of speed and regretting the flames often surprise firefighters. There are several stream of research that try to lay the groundwork on a subject as sensitive of this deflagrant phenomenon, but without reaching the same conclussions. There are contradictions between different theories, and oficial science is far from reaching a consensus. Therefore, the objective of the study is to evaluate currently existing theories and apply them to cases founded development of this blowup fires, based on established theories and some fatalities that have been documented. It¿s intended to evaluate the meaning of these theories is better focused on explain the phenomenon, in addition to establish bases for its prevention. It¿s evident that such a phenomenon cannot be eradicated, but it¿s posible mitigate his consequences and try to explain the contitions in which happen in order to prevent it on time.

Smoldering fires represent domestic, environmental and industrial hazards. This flameless form of combustion is more easily initiated than flaming, and is also more persistent and difficult to extinguish. The growing demand for non-fossil fuels has increased the use of solid biofuels such as biomass. This represents a safety challenge, as biomass self-ignition can cause smoldering fires, flaming fires or explosions. Smoldering and extinguishment in granular biomass was studied experimentally. The set-up consisted of a cylindrical fuel container of steel with thermally insulated side walls. The container was closed at the bottom, open at the top and heated from below by a hot surface. Two types of wood pellets were used as fuel, with 0.75-1.5 kg samples. Logistic regression was used to determine the transition region between non-smoldering and self-sustained smoldering experiments, and to determine the influence of parameters. Duration of external heating was most important for initiation of smoldering. Sample height was also significant, while the type of wood pellet was near-significant and fuel container height was not. The susceptibility of smoldering to changes in air supply was studied. With a small gap at the bottom of the fuel bed, the increased air flow in the same direction as the initial smoldering front (forward air flow) caused a significantly more intense combustion compared to the normal set-up with opposed air flow. Heat extraction from the combustion was studied using a water-cooled copper pipe. Challenges with direct fuel-water contact (fuel swelling, water channeling and runoff) were thus avoided. Smoldering was extinguished in 7 of 15 cases where heat extraction was in the same range as the heat production from combustion. This is the first experimental proof-of-concept of cooling as an extinguishment method for smoldering fires. Marginal differences in heating and cooling separated smoldering from extinguished cases; the fuel bed was at a heating, Schwelbrände repräsentieren Brände die eine Gefahr im häuslichen, ökologischen und industriellen Umfeld darstellen. Diese flammenlose Form eines Brandes ist leichter zu starten, stabiler im Verlauf und schwieriger zu löschen als Flammenbrände. Die wachsende Nachfrage nach nicht fossilen Brennstoffen hat die Verwendung von festen Bioenergieträgern, wie Biomasse, erhöht. Daraus resultieren neue Sicherheitsanforderungen, da die Selbstentzündung fester Biomasse einen Schwelbrand, einen Brand oder eine Explosion verursachen kann. Schwelen und Löschen von granularer Biomasse wurde experimentell untersucht. Der experimentelle Aufbau bestand aus einem zylindrischen Brennstoffbehälter aus Stahl mit wärmeisolierten Seitenwänden. Der Behälter wurde unten geschlossen, oben offen gelassen und von unten durch eine heiße Oberfläche erhitzt. Als Brennstoff wurden zwei Arten von Holzpellets, in Proben von 0,75 kg bis 1,5 kg, verwendet. Um den Übergang von nicht Schwelen zu selbständigem Schwelen und die beeinflussenden Parameter zu bestimmen, wurde logistische Regression verwendet. Um Schwelbrand zu erzeugen, war die Dauer der externen Erwärmung am wichtigsten. Die Probenhöhe war ebenfalls signifikant, während die Art der Holzpellets nahezu signifikant war, wobei die Höhe des Brennstoffbehälters nicht signifikant war. Die Anfälligkeit des Schwelens gegenüber Änderungen der Luftzufuhr wurde untersucht. Mit einem kleinen Spalt am Boden des Behälters, ergab der erhöhte Luftstrom in der gleichen Richtung wie die anfängliche Schwelbrandfront (Vorwärtsluftstrom) eine signifikant intensivere Verbrennung im Vergleich zu der normalen Anordnung mit Rückwärtsluftstrom. Die Wärmeentnahme aus der Verbrennung wurde mithilfe eines wassergekühlten Kupferrohres untersucht. Dadurch wurden Probleme in Verbindung mit direktem Brennstoff-Wasser-Kontakt (Aufquellen des Brennstoffes, Wasserkanalisierung und-abfluss) vermieden. Der Schwelbrand wurde in 7 von 15 Fällen gelöscht, wobei die Menge des Wärmever, EMRIS, emerging risks from smoldering fires

Due to an increase in the number of large-scale façade fires around the world the interest in the fire hazards of façades has also increased. The hazards of such fires have been acknowledged since earlier and many different test methods have therefore been developed to enable evaluation of the fire properties of wall assemblies. The purpose of this study is to map differences and similarities between existing full-scale test methods that are currently used to evaluate façade systems based on their performance when influenced by fire. The study also includes a review of previous research into parameters and conditions that influence a façade fire. Some past incidents will be used to enable comparison between the tests and a real fire scenario. The review of previous research has been focused in the areas fire spread, fire properties influencing the heat flux from a fire, and comparative studies evaluating differences between existing test methods. For the study of parameters in existing test methods 21 test methods have been identified and included in the study. A detailed compilation of information on each of the included test methods can be found in the tables included in appendix A. The mapping of the differences and similarities of the included methods has resulted in comparisons of wall and specimen specifications, ignition source parameters, measuring points and approval criteria. The increase in interest for façade fire hazards has also led to some new methods being developed and old methods being revised. New methods and unfinished revisions have not been included in the comparison study but are mentioned. The conclusion of this study is that although the variation between the tests on the detailed methodology level are very high, if you consider the conditions used for approval and evaluation, they can all be linked to identified hazards of façade fires. However, there are some parameters that need to be re-examined. Previous research indicates that the fir

This report covers the creation of a dynamic fire propagation method for a real-time environment. The purpose is to see if it is possible to create a system that can control fire propagation behaviour and visual design based on some sort of simple parametrization, the purpose stems from the lack of a system to control and design a fire propagation scenario. To attain the results, a fire propagation method is devised based on the purpose of having a parameter based system, this method is created through the use of scripting in a real-time game engine to control visuals and behaviour of built in particle systems. Results show fire propagation through an example scenario where the fire behaves differently based on the material that is burning, based on parameters set by an artist. These results conclude that is it possible to create a parameter based fire propagation system and that it can be used to change the visual design and behaviour and be expanded to provide better artist input and control. The report suggests further research in the area of simplified controlled fire simulation in real-time engines, and usability., Den här rapporten täcker skapandet av en metod för dynamisk eldspridning i en realtidsmiljö. Syftet är att se om det är möjligt att skapa ett system som kan kontrollera spridningsbeteendet och den visuella designen av elden baserat på någon sorts simplifierad parametrisering, Syftet härstammar ifrån att det saknas system där man kan kontrollera och designa ett eldspridningsscenario. För att nå resultat så skapas en metod som är baserad på syftet att använda ett parameterbaserat system, denna metoden skapas med hjälp av programmering i en realtidsmotor genom att kontrollera det visuella samt beteendet hos inbyggda partikelsystem. Resultatet visar eldspridning genom ett exempelscenario där elden beter sig olika baserat på vilket material som brinner, baserat på parametrar som är satta av en artist. Slutsatsen av resultatet visar att det är möjligt att skapa ett parameterbaserat eldspridningssystem och att det kan användas för att kontrollera den visuella designen och beteende samt att det kan expanderas för att förse artister med bättre kontroll över systemet. Rapporten föreslår fortsatta studier inom området simplifierade kontrollerade eldsimulationer inom realtidsmotorer, och användarvänlighet.

To build multi story buildings out of timber is of a common interest in the building sector. Timber as a building material has many profits, such as the low cost, the availability and the ability to recycle it, the low carbon footprint and the workability. Although, when it comes to fire protection of buildings with a timber based structure there are challenges regarding prevention of the spread of fire while timber surface is exposed to fire. There have been cases in which timber buildings have caught fire leading to severe fire spread and ruined buildings. One example concerns a student modulus accommodation in Luleå that caught fire in august 2013. The fire started on the fourth floor after which a vertical fire spread occurred in concealed spaces between the volume modules. According to the fire investigation lack of knowledge regarding performance of detailed building solutions has led to the poor fire performance of the building. This master thesis mainly consists of a model scale tests that is prepared and performed according to the standard EN 1363-1. The purpose of the test is to investigate the performance of various cavity barriers exposed to fire. The main objective is to examine which temperatures that can be expected at different positions at various cavity barriers when using model scale test as a test method. There are two main kinds of cavity barriers: barriers that are airtight and closed inside the voids of the construction; and ventilated barriers. The most common cavity barriers are the ones that are airtight and closed. The material can be solid wood, gypsum board or mineral wool. The installation areas for these cavity barriers are anywhere, besides where the concealed spaces shall be ventilated and in every joint that shall be sealed using sealant. The ventilated cavity barriers are mounted in concealed spaces where the ventilating function is provided. These concealed spaces are often situated in, for example, ventilated attics, facades and

A study is presented in the report regarding fires that have occurred in the USA between 2007 and 2015 in tall residential buildings with wood frame. The work is based on fire investigations compiled by NFPA and does only include large-scale fires and fatal fires. The general conclusions that have been made are that sprinklers have a positive impact on the extent of a fire and that an installation of sprinkler in buildings save lives. The sprinkler system operated in 96,7 % of the studied cases, but only operated effectively in 68 % of the cases. Further, in buildings established in the 1970s, fires spread outside the original fire compartments in all the studied cases. In buildings built after the 1970s, the percentage of fires that spread outside the original fire compartment was reduced to below 50 percent for each decade. The last conclusion is that to prevent fire spread between fire compartments in wood buildings, it is important that the detailed construction solutions are properly executed.

Green roofs are becoming increasingly more popular due to the fact of their many benefits. The aim of this report is to investigate the level of fire safety in extensive green roofs, which includes a variety of sedum, herbs and grass, in urban environments. Research is also done to clarify which parameters are affecting fire spread on extensive green roofs and to which extent. The objective was to present strategies and measures to lower the risk of ignition and flame spread. The report was conducted through a literature study on the subject extensive green roofs in addition with two different experiments investigating fire spread and vertical temperature influence in the case of a fire in extensive green roofs. It was concluded that the risk for a substantial fire spread in extensive green roofs was low and largely dependent on the level of moisture in the material. Furthermore, the tests implied that such a roof covering (including growing medium) provided sufficient fire protection to the underlying layers.

The aim of this thesis is to study the flammability and fire spread for textile membranes for weather protection. This thesis includes literature studies to determine current standards and recommendations available. Main focus however have been on the European classification system EN 13501-1 and construction site safety. Two types of experimental tests have been done, cone calorimeter test and tests according to European standard EN ISO 11925-2. In the cone calorimeter data regarding heat release rate and smoke production were collected. The tests according to EN ISO 11925-2 were performed at SP Technical research Insitiute of Sweden’s facilities in Borås and the cone calorimeter test at the fire laboratory of LU. In total, six different textile membranes for weather protection were tested. The outcome of this experiment was that one out of six tested membranes achieved a Euroclass higher then E, four fail the test and got Euroclass F and one could not be classified due to lack of material. Conclusions drawn from this thesis were that textile membranes for weather protection overall have poor fire behavior and regulations on the area need to be developed using todays developed standards.

This is a summary analysis of the main aspects involved in fire vulnerability and development in wildland-urban interface areas. Records of actual fires occurring in recent years have been collected, especially from 2014 as this was considered the year with the greatest disasters caused by this type of fire. Based on fieldwork and fire forecast analysis, results indicate that the response time for the first attack is the determining factor in the possibility of success in the timely containment of fire advance., Il se présente une analyse résumée des principaux aspects techniques, économiques et sociaux qui interviennent dans la vulnérabilité etle développement des incendies dans les zones d'interfaces urbaine-forestières. Des informations dérivées d'incendies réels dans les dernières années ont été recueillies, en mettant l'accent sur l'année 2014 comme étant l'année avec le plus de catastrophes résultant de ce type d'incendies. Les résultats basés sur le travail de terrain et les analyses de pronostics d'incendies, montrent que le temps de réponse à la première attaque est un facteur déterminant dans la Les incendies de forêt, l'interface forêt-urbaine, la protection civile, risques d'incendie, la propagation du feu.possibilité de la réussite du confinement de l'avancée du feu., Apresenta-se um resumo dos principais aspetos técnicos envolvidos no desenvolvimento da vulnerabilidade a incêndios em áreas de interface florestal-urbano. Recolheram-se dados procedentes de incêndios reais ocorrido nos últimos anos, especialmente de 2014, por ser considerado o ano mais catastrófico neste tipo de incêndios. Os resultados, com base no trabalho de campo e análise de previsão fogo, mostram que o tempo de resposta do primeiro ataque é o fator determinante, na possibilidade de sucesso para a contenção oportuna da propagação do fogo., Se presenta un análisis resumido de los principales aspectos técnicos que intervienen en la vulnerabilidad y desarrollo de incendios en áreas de interfaz urbano-forestal. Se recopilaron antecedentes derivados de incendios reales sucedidos en los últimos años, con énfasis en 2014 por ser considerado el año con mayores catástrofes producto de este tipo de incendios. Los resultados basados en trabajo de campo y análisis de pronóstico de incendios, demuestran que el tiempo de respuesta al primer ataque es el factor determinante en la posibilidad de éxito en contención oportuna del avance del fuego.

This is a summary analysis of the main aspects involved in fire vulnerability and development in wildland-urban interface areas. Records of actual fires occurring in recent years have been collected, especially from 2014 as this was considered the year with the greatest disasters caused by this type of fire. Based on fieldwork and fire forecast analysis, results indicate that the response time for the first attack is the determining factor in the possibility of success in the timely containment of fire advance., Il se présente une analyse résumée des principaux aspects techniques, économiques et sociaux qui interviennent dans la vulnérabilité etle développement des incendies dans les zones d'interfaces urbaine-forestières. Des informations dérivées d'incendies réels dans les dernières années ont été recueillies, en mettant l'accent sur l'année 2014 comme étant l'année avec le plus de catastrophes résultant de ce type d'incendies. Les résultats basés sur le travail de terrain et les analyses de pronostics d'incendies, montrent que le temps de réponse à la première attaque est un facteur déterminant dans la Les incendies de forêt, l'interface forêt-urbaine, la protection civile, risques d'incendie, la propagation du feu.possibilité de la réussite du confinement de l'avancée du feu., Apresenta-se um resumo dos principais aspetos técnicos envolvidos no desenvolvimento da vulnerabilidade a incêndios em áreas de interface florestal-urbano. Recolheram-se dados procedentes de incêndios reais ocorrido nos últimos anos, especialmente de 2014, por ser considerado o ano mais catastrófico neste tipo de incêndios. Os resultados, com base no trabalho de campo e análise de previsão fogo, mostram que o tempo de resposta do primeiro ataque é o fator determinante, na possibilidade de sucesso para a contenção oportuna da propagação do fogo., Se presenta un análisis resumido de los principales aspectos técnicos que intervienen en la vulnerabilidad y desarrollo de incendios en áreas de interfaz urbano-forestal. Se recopilaron antecedentes derivados de incendios reales sucedidos en los últimos años, con énfasis en 2014 por ser considerado el año con mayores catástrofes producto de este tipo de incendios. Los resultados basados en trabajo de campo y análisis de pronóstico de incendios, demuestran que el tiempo de respuesta al primer ataque es el factor determinante en la posibilidad de éxito en contención oportuna del avance del fuego.

Four different methodologies for calculating the ignition of different components on a mining vehicle in a mine drift were analysed. The results were compared with two full-scale fire experiments on mining vehicles. The four different methods are based on physical relations for fire spread between combustible components of the mining vehicles. The first two methods use a critical heat flux as ignition criterion while the other two methods use an ignition temperature. A sensitivity analysis was performed and the most influencing parameter of the methods was further analyzed. The calculated results were compared with the measured results from the experiments. The two methodologies applying an ignition temperature criterion were ruled out at as the surface temperatures of all fuel components never achieved the corresponding ignition temperatures. For the two methods applying a critical heat flux criterion it was found that the expression not including a flame radiation term was not suitable as it was found that the flame radiation played an important part with respect to spread mechanisms. The expression containing a flame radiation term was found to come very close to the observed ignition times, except in the case of the left, rear tyre of the drilling rig where it predicted a much higher ignition time than the one observed. The difference is unclear and would have to be investigated further. It was also found that the surface heat losses had none effect on the output results and could therefore be neglected in the calculations. In the case of the wheel loader the calculated heat release rate curves did not match the measured curve as well as in the case of the drilling rig. The difficulty in this case consists of accurately predicting the mechanical failure of a component - in this case a suction hose - that would initiate the very significant hydraulic oil pool fire.

High temporal resolution information on burnt area is needed to improve fire behaviour and emissions models. We used the Moderate Resolution Imaging Spectroradiometer (MODIS) thermal anomaly and active fire product (MO(Y)D14) as input to a kriging interpolation to derive continuous maps of the timing of burnt area for 16 large wildland fires. For each fire, parameters for the kriging model were defined using variogram analysis. The optimal number of observations used to estimate a pixel's time of burning varied between four and six among the fires studied. The median standard error from kriging ranged between 0.80 and 3.56 days and the median standard error from geolocation uncertainty was between 0.34 and 2.72 days. For nine fires in the south-western US, the accuracy of the kriging model was assessed using high spatial resolution daily fire perimeter data available from the US Forest Service. For these nine fires, we also assessed the temporal reporting accuracy of the MODIS burnt area products (MCD45A1 and MCD64A1). Averaged over the nine fires, the kriging method correctly mapped 73% of the pixels within the accuracy of a single day, compared with 33% for MCD45A1 and 53% for MCD64A1. Systematic application of this algorithm to wildland fires in the future may lead to new information about vegetation, climate and topographic controls on fire behaviour. © IAWF 2014.

The purpose of this report was to examine if there was an easy way for the rescue services to get knowledge about the possible consequences regarding a fire in an area of densely-built wooden buildings. By following the method proposed in this report rescue services can get an understanding if their capacity to combat a fire in this type of area is sufficient. The method is originated in two pathways of fire spread and by dividing them into sub-models and using typical parameter values for the area type a resulting checklist was obtained. The method can be used to determine the time until fire spread for six typical configurations and how many houses that will be subjected to a radiation level higher than the critical radiation level for wood., Värdering av brandspridningsrisker i tät trähusbebyggelse I tät trähusbebyggelse kan en uppkommen brand snabbt sprida sig till intilliggande byggnader och det finns även förutsättningar för att branden skall utvecklas och bli omfattande. Men frågan är hur omfattande kan en brand kan bli? Och inom vilken tidsram kan brandspridning ske? I detta arbete presenteras en metod som räddningstjänsten kan använda för att besvara dessa frågor. Historiskt har trä varit ett vanligt förekommande byggnadsmaterial och är så än idag. Detta är till följd av att Sverige ligger vid det norra barrskogsbältet och det finns god tillgång till rakvuxet virke. Historiskt har det också varit vanligt att husen byggdes tätt för att effektivt nyttja tillgänglig yta. När dessa två karaktärsdrag kombineras blir följden ofördelaktig, sett ur brandteknisk synpunkt. Detta då trä, till skillnad från andra vanliga byggnadsmaterial så som betong eller tegel, är brännbart. Samtidigt innebär kortare avstånd fler möjliga spridningsvägar. Bränder i tät trähusbebyggelse kan därmed få förödande konsekvenser. Detta har också visat sig i historien då ett antal större bränder har uppkommit och i vissa fall har hela städer brunnit ner. På sina ställen finns fortfarande bebyggelsetypen kvar och därmed även brandriskerna. Den täta trähusbebyggelsen är en del av det svenska kulturarvet och värt att bevara. Utöver det kulturella värdet så innebär en brand i bebyggelsetypen också en risk för andra värden så som människors liv och hälsa, samt ekonomiska. Räddningstjänsten har en naturlig del i hanteringen av dessa risker. Det är därför intressant för dem att kunna bedöma sin egen förmåga och hur väl den räcker till för att hantera ett sådant scenario. Generellt finns det god kunskap inom räddningstjänsten om de egna resurserna men det har funnits svårigheter i att skapa ett underlag att väga dessa mot. I arbetet presenteras en metod för hur räddningstjänsten ska kunna bedömmma konsekvensen av en brand. Resultatet kan k

The purpose of this report was to examine if there was an easy way for the rescue services to get knowledge about the possible consequences regarding a fire in an area of densely-built wooden buildings. By following the method proposed in this report rescue services can get an understanding if their capacity to combat a fire in this type of area is sufficient. The method is originated in two pathways of fire spread and by dividing them into sub-models and using typical parameter values for the area type a resulting checklist was obtained. The method can be used to determine the time until fire spread for six typical configurations and how many houses that will be subjected to a radiation level higher than the critical radiation level for wood.

The purpose with the thesis is to compare reasons to why fire-related spreads occur in apartment buildings and examine the significanse for the extent of property damage. The aim is to provide a basis for judging the risk of property loss and need of improved property safety in case of fire in the apartment buildings. The report has shown that several spreads have occurred through the apartment door to the stairwell, often in the form of smoke. The result also shows that the building material is rarely critical to fire safety. It is not necessarily a heightened risk of spread between compartments due to burnable building materials like cellular plastic insulation or wood alone. However, there are trends in the analysis showing that the material could be of greater significance in larger fires, but it is difficult to determine from the limited sample used in the thesis.

A method for performed experiments using stationary gas burners and liquid fuel-soaked wicks to study flame geometry and buoyant instabilities important to fundamental wildland fire behaviour has been developed. This thesis focuses on experiments performed with stationary fires to carefully study instabilities observed in spreading fires that suggest they play a critical role in fire spread. Two types of flow conditions were used to perform experiments similar to wildfire spread conditions: sloped fuel surface and forced-flow (wind aided). Small- scale inclined experiments for performed at the University of Maryland with liquid- fuel soaked wicks and large-scale experiments at the USDA Forest Service Missoula Fire Sciences Laboratory with a gas-burner. These experiments were performed with over a range of heat-release-rates and burner sizes for angles from 0 to 60 degrees from the horizontal. Forced-flow experiments were performed in a large-scale wind tunnel at the Missoula Fire Laboratory and at the University of Maryland with a well characterized wind blower with gas-burners. These experiments were performed for a range of heat-release-rates and burner sizes in wind speeds from 0.2 to 3.0 ms−1 The flame geometry was determined using high-speed videography. Important two-dimensional flame geometry parameters such as centerline flame length and flame tilt angle were measured from these images. Flame intermittency and pulsation close to the surface was measured using high-speed videography and micro-thermocouples. A method was developed to track the extension of the flame close to the surface which would come in direct contact with unburnt fuels ahead of the fire. These methods showed that the pul- sation frequency is complicated suggesting large scale structures in the flow. Using these frequency the stationary experiments follow similar Strouhal-Froude scaling for flame pulsations in spreading fires. Stream-wise streaks in the flow were observed and measured

This paper highlights the challenges the fire and rescue services can meet at façade fires involving EPS insulation during construction and use of a building. The EPS characteristics are discussed in respect to the fire and rescue operation and results from orientating fire tests performed at a fire and rescue services training and test field are presented. Types of evacuation solutions, involving the fire and rescue services, where façade fires can delay or completely rule out the possibilities for safe evacuation, are presented. The restrictions in the Swedish building codes regarding use of combustible insulation are analysed and reflections over the practical problems with following the instructions to keep an EPS insulated façade safe through the building’s whole lifespan are made. A number of occurred fires involving EPS are discussed and analysed from a fire and rescue perspective. Finally, recommendations are given for the fire and rescue services and future research fields are proposed.

A total of six fire tests were conducted in a mock-up of a subway carriage that is about 1/3 of a full wagon length. They were carried out under a large scale calorimeter in a laboratory environment. The aim of the tests was to investigate the initial fire growth in a corner scenario using different types of ignition sources that could lead to a flashover situation. The ignition sources used were either a wood crib placed on a corner seat or one liter of petrol poured on the corner seat and the neighboring floor together with a backpack. The amount of luggage and wood cribs in the neighborhood of the ignition source was continuously increased in order to identify the limits for flashover in the test-setup. The tests showed that the combustible boards on parts of the walls had a significant effect on the fire spread. In the cases where the initial fire did not exceed a range of 400 – 600 kW no flashover was observed. If the initial fire grew up to 700 – 900 kW a flashover was observed. The maximum heat release rate during a short flashover period for this test set-up was about 3.5 MW. The time to reach flashover was highly dependent on the ignition type, wood cribs or backpack and petrol.

The focus of this study is on spatially segregated multiple crown fuel matrices that model the crowns of discrete shrubs. The influence of the horizontal crown separation distance between crown fuel matrices on the transition process from surface fires to crown fires and on the rate of spread of surface fires in chaparral fuels is investigated experimentally and numerically. The experiments are carried out in a 1.20 m width × 1.20 m height × 7.4 m length, open-roof wind tunnel to ensure that flame-generated buoyancy effects are not suppressed. The surface fire is initiated in a fuel bed comprised of aspen (Populus tremuloides Michx) excelsior that is evenly distributed over an area of 0.8 m width × 2.8 m length to a depth of 0.10 m. Crown fuel matrices comprised of live chamise (Adenostoma fasciculatum) held in place by two 0.6 m length × 0.3 m height × 0.8 m width wire mesh baskets, at a height of 0.35 m from the surface of the fuel bed. Crown separation distances (CSD) investigated range from 0.1 m to 0.3 m. At a CSD of 0.1 m, as the fire front approaches and ignites the downwind crown fuel matrix, the surface fire and upwind crown fires are merged into a single fire. Following ignition of the downwind crown fuel, a single merged fire, comprising the surface and two crown fires, results. At larger crown separation distances of 0.2 m and 0.3 m, the surface and upwind crown fires are segregated, appearing as two distinct fire fronts, with the ignition of the downstream crown fuel matrix occurring earlier in time for the lower CSD case. In addition, a Particle Image Velocimetry system is utilized to investigate the influence of CSD on the flow field between adjacent crown fuel matrices.

In 2002 an amendment was added to the International Convention for the Safety of Life at Sea (SOLAS) which opened up for shipbuilders to replace steel with lightweight materials in the superstructures. However, SOLAS requires equal fire safety compared to ships with steel superstructures. LASS-c is a cross-organizational project with the aim to find a method to build cruise ships with part of the superstructure made in lightweight materials. As a part of the LASS-c project the purpose of this thesis has been to develop an application in Java (FISPAT). The tool has been designed to find fire sensitive areas in structures such as cruise vessels. A second aim with the thesis has been to evaluate the cruise ship Norwegian Gem with respect to fire sensitive areas. In FISPAT the user can make a model of a structure. The model is built up by rooms, networks and devices. With the model, FISPAT can simulate fire spread and the effects on the networks included in the model. The user can then analyze the results to find fire sensitive parts. One of the main results in this thesis is the tool itself together with this report which also serves as a manual to FISPAT. An evaluation of Norwegian Gem was also made which points to some critical parts of the ship. One example is the main water supply pipe to the sprinklers which has no redundant systems and all sectioning valves are manually operated, hence it is vulnerable to faults. The electrical feed to the three pump units is also a vulnerable point on the vessel. The pumps have redundant electrical networks, but the wires are drawn on the same paths, making it possible to take out both systems with one fire.

A model for predicting the trajectory of window flame ejected from a fire compartment was formulated incorporating the effect of wall above the opening. Based on the observation in the reduced scale experiments, window flames were divided into the following categories with regard to its trajectory configuration: the flow which ascends almost vertically up after ejection maintaining a certain separation from the wall; and the flow which ascends upward after ejection and gradually approaches to the wall in the downstream. In the model, trajectories of these flows were approximated by cubic polynomials whose coefficients were given as functions of a dimensionless parameter F*. The parameter F* was derived from the conservation equation of momentum which incorporates the effect of pressure gradient across the ascending flows. Critical condition for the occurrence of flow attachment was described as a proportion of the maximum separation from the wall versus the opening width. Trajectories predicted by the proposed model were then compared with the measurement data which indicated reasonable agreements.

A computational model for fire spread in a densely built urban area is developed. The model is distinct from existing models in that it explicitly describes fire spread phenomena with physics-based knowledge achieved in the field of fire safety engineering. In the model, urban fire is interpreted as an ensemble of multiple building fires; that is, the fire spread is simulated by predicting behaviors of individual building fires under the thermal influence of neighboring building fires. Adopted numerical technique for the prediction of individual building fire behavior is based on the one-layer zone model. Governing equations of mass, energy, and chemical species in component rooms are solved simultaneously, for the development of temperature, concentrations of chemical species, and other properties. As for the building-to-building fire spread, three mechanisms are considered as contributing factors of fire spread, i.e., (I) thermal radiation from fire-involved buildings; (II) temperature rise due to wind-blown fire plumes; and (III) firebrand spotting. As for the model verification, fire spread simulations were carried out in a hypothetical urban area, where 2500 buildings of identical configuration were aligned at constant separations. Calculated fire spread rates were then compared with that of the Hamada model, and reasonable agreements were obtained. The model was further verified with the record of a past urban fire, which took place in the city of Sakata in 1976. Although the general features of the fire spread were similar, there were certain discrepancies in the eventual burnt area. The reasons for these discrepancies were discussed and issues for future refinements were stated.

This paper gives an overview of the tunnel fire research, both experimental and theoretical work with the exception of computer modelling. The overview shows that the critical velocity for longitudinal flow in a tunnel is the single most well investigated fire phenomenon found in the tunnel fire research literature. This knowledge has reached a high level but there are still some areas that need to be investigated further. For example, very little work has been done on backlayering of smoke upstream a fire and cross-sectional effects on heat release rates, temperatures, flame lengths, fire spread and toxic conditions. Extensive work using model scale tunnels has contributed with new information and clarified many phenomena but the lack of good large scale experimental data is and will be a key issue in near future. This concerns mainly the correlation between heat release rate and maximum ceiling temperatures, the influence of ventilation on maximum heat release rate and fire growth rate and fire spread in and between vehicles. The extensive theoretical work which has been conducted concerning the effects of ventilation on heat release rates needs to be further investigated in large scale tests.

A simple simulation model has been used to investigate whether large fires in Mediterranean regions are a result of extreme weather conditions or the cumulative effect of a policy of fire suppression over decades. The model reproduced the fire regime characteristics for a wide variety of regions of Mediterranean climate in California, France and Spain. The Generalised Likelihood Uncertainty Estimation (GLUE) methodology was used to assess the possibility of multiple model parameter sets being consistent with the available calibration data. The resulting set of behavioural models was used to assess uncertainty in the predictions. The results suggested that (1) for a given region, the total area burned is much the same whether suppression or prescribed fire policies are used or not; however fire suppression enhances fire intensity and prescribed burning reduces it; (2) the proportion of large fires can be reduced, but not eliminated, using prescribed fires, especially in areas which have the highest proportion of large fires.

The purpose of the present study is to explore and validate the efficiency and accuracy of the predictive capability of CFD models for fully developed natural fires in large compartments. The FDS CFD software was used to simulate three large-scale fire tests. The fire tests (nine in total) had been carried out in 1993 at Cardington UK, in collaboration with BRE/FRS and CORUS (British Steel at that time). The main parameters of the three chosen large-scale fire tests are the compartments dimensions, the fire load, the ventilation opening, and the ignition type. The duration of the fire tests, starting from the ignition until the extinction of the fire, was between 70-120 min and the fire source was wooden cribs. The simulations were in full time and full scale. The FDS model solves numerically the well known Navier-Stokes equations with emphasis on smoke and heat transport from fires. It uses a mixture fraction combustion model assuming that combustion is mixing controlled, and that the reaction of fuel and oxygen is infinitely fast. Turbulence is treated by means of the Smagorinsky form of Large Eddy Simulation, while thermal radiation is computed using a finite volume technique. Despite the assumptions made and the complex phenomena involved, the correlation between the computational and experimental results was in very good agreement. The fire spread was modelled accurately and the difference for the peak temperatures was 5%-20%. However the results are sensitive to some input parameters and so each fire scenario should be treated individually for a robust and accurate solution.

Important phenomena related to tunnel fires are presented including both experimental and theoretical work. The main focus is on the large-scale fire tests performed in 2003, in the Runehamar tunnel in Norway. During these tests heat release rate (HRR), temperatures, gas concentrations (O2, CO2, CO, HCN, and H2O), velocities, radiation, and smoke were measured. Four tests with a set-up simulating HGV cargos were performed with fuel loads constituting of different mixtures of cellulose and plastic. The fuel load ranged from 2850 kg to 11010 kg giving maximum HRRs between 66 MW and 202 MW. The results showed that ordinary (non-hazardous) cargo can give HRRs and temperatures normally expected to be related only to hazardous goods (e.g. tanker fires). Thus, the highest HRR and gas temperature were far higher than that suggested by most tunnel design guidelines. A close correlation between the maximum HRR and energy content is presented for passenger cars and HGVs. It has also been shown in the Runehamar tests that the fire in an HGV can spread a long distance downstream in a tunnel, of the order of 100 m. Based on the test results and real incidents one must emphasize the importance of the incident operation during the first five to ten minutes of the fire. The actions of the people inside the tunnel and the rescue personnel during this time period can be crucial to the outcome. During two of the fire tests, large pulsations of the gas flow inside the tunnel were observed. These pulsations were registered only when the measured heat release rate was higher than 125 MW - 135 MW. Two different periods of pulsations were registered, short periods of approximately 4 s and longer periods of approximately 18 s. The pulsations are presented and explanations are given, using two different approaches: an acoustic approach and a frequency response analysis based on an impedance approach. The intrinsic resonances of the system proved to be close to the periods found in the experim

The current approach for the characterization of secondary damage associated with a weapon hit has evolved over several Total Ship Survivability (TSS) and Battle Damage Repair Assessment (BDRA) evaluations. The genesis of the current methodology was rudimentary fire spread times, developed by the Naval Research Laboratory (NRL) and Hughes Associates, Inc., based on USS Stark incident data and testing. This information was implemented in a TSS model developed by the Naval Surface Warfare Center, Carderock Division (NSWC/CD). The fire spread methodology was subsequently improved and the framework was expanded to allow for smoke spread during the evaluation performed for the LPD- 17 VAR 2. Most recently, the methodology was further refined during the CVNX assessment. This report reflects the most current methodology used for the VAR 3 process for the LPD-17 platform detailed design. This approach is proposed to be adopted for T-AKE.

Developing an Effective Spatial Fuel Treatment Strategy to Reduce Wildfire Spread and Intensity Levels on the Colorado Front Range

Development and Testing of a Physics-Based Model For the Prediction of Fire Spread and Intensity

Heathlands typically experience regimes consisting of frequent and intense fires. These fire regimes play important roles in the lifecycles and population dynamics of all species in these communities. Prescribed fire is commonly applied to heathlands to minimise the risk of wildfires as well as to promote biodiversity. Ignitions in heathlands tend to either be unsustainable, or quickly develop into rapidly spreading intense fires. This presents a major problem for the application of prescribed fire and is the primary focus of this thesis. Heathland ignition has been investigated in three sections; litter ignition; vertical development of fire into the shrub layer; and horizontal spread through the shrub layer. These were studied in laboratory experiments using miniature versions of field fuels. Ignition success in litter layers was related to the dead fuel moisture content. Litter type, ignition source, and presence of wind were found to affect the range of ignitable fuel moisture contents of a litter bed. The effect of litter type was best explained by density. Dense litter beds required drier conditions for ignition than low density litter beds. The vertical development of fire into shrubs was mostly dependent on live fuel moisture content, but crown base height, presence of wind, ignition source, shrub height and the percentage of dead elevated fuel were also important. Horizontal spread of fires through shrub layers was most affected by the presence of a litter layer, with nearly all ignitions successful when there was an underlying litter fire. Fire spread would only occur in shrubs without a litter layer when the shrub layer was dense and dry, or had a substantial dead fuel component. Spread was more likely to be sustained when there was wind. Models predicting the moisture content of dead fuels were tested in heathlands, and as would be expected those that can be calibrated for different fuel types were found to have the best performance. Fuel moisture conten

The propagation of fire-generated smoke with a counter-flow air supply in, a horizontal arrangement of shipboard compartments and passageways was modeled using a computational fluid dynamics program generated by Computational Fluid Dynamics Research Corporation. This study was based on a large-scale live fire experiment performed by Naval Research Laboratory on the ex-USS SHADWELL. All simulations were evaluated at steady state conditions. A constant velocity counter-flow air supply was introduced into the model structure. The counter-flow air velocities used were 0.5, 1, and 2 m/s. This study used a computational fluid dynamics combustion module to simulate a 620 kW fire generated by the complete combustion of propene gas from a burn pan in the space.: Carbon dioxide from the fire was tracked throughout the structure to model smoke propagation. Seven simulations were performed with adiabatic and isothermal bulkhead, deck and overhead boundary conditions. Simulation smoke propagation results were consistent with experimental observations. Figures depicting temperature' distribution, carbon dioxide distribution and mixture flow patterns at specified locations are provided in the report The goal of this study is to evaluate the effectiveness of computational fluid dynamics modeling of smoke propagation in a shipboard space with a counter-flow air supply., Original contains color plates: All DTIC reproductions will be in black and white.

The second generation U. S. firespread model - final report 1999

Efforts at comparing simulated and observed fire growth patterns

The full-scale International Standards Organization (ISO) 9705 Room/Corner Test is currently used to regulate compartment-lining materials in the High Speed Craft (HSC) Code. This test method involves the use of large amounts of material so that the test method is an impediment in developing new materials. Bench-scale tests like the Cone Calorimeter and the lateral Ignition Flame Test (LIFT) Apparatus may provide indications of full-scale performance in the ISO 9705. The objective of this work is to assess if correlations and mathematical models based on bench-scale data can predict material performance in the ISO 9705 Test. The results of this project show that it is possible to learn a great deal about the expected performance of materials in the ISO 9705 Test from bench-scale tests like the Cone Calorimeter and the LIFT Apparatus. Both the simple correlations using the Flammability Parameter deduced from the Cone Calorimeter and the mathematical models using Cone Calorimeter and LIFT data provided clear insights into the burning behavior of materials in the ISO 9705 Test. The Flammability Parameter deduced from Cone Calorimeter data was able to correlate the heat release rate and time to flashover in the ISO 9705 Test. This provides the opportunity to obtain significant information concerning expected ISO 9705 performance from a few tests of small samples. It is significant that LIFT results are not required to allow correlation of the performance of U.S. Coast Guard (USCG) HSC Materials. The mathematical models performed well in predicting the heat release rate and time to flashover in the ISO 9705 Test. These more sophisticated methods provide additional confidence in the ability of bench-scale tests to be used to predict the performance of materials in the ISO 9705 Test. Further, these models have the potential to allow prediction of realistic scenarios, which differ from the ISO 9705 Test method., Prepared in cooperation with Hughes Associates, Inc., Baltimore, MD.

Crown Fire Spread Rate Modeling

A Report

The second generation U. S. firespread model - final report 1994

Fire History of the Southern Black Hills, South Dakota