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In this paper, our proposed method based on FDS version 6 (Fire Dynamic Simulation) simulation fire models of backdraft. After output FDS Excel data input it in Unity 3D game engine. These steps can improve Unity 3D game engine fire model more effective smoke location and backdraft fire model more realism. From FDS output Excel file data is smoke density and 3D space coordinates. Use it change default Unity 3D game engine's particle system, and make physically real word fire model in game engine, coordinates in the original particle system and change PhysX code. Computing the coordinates of smoke effect is very difficult thing. The Unity 3D game engine 4.2 versions have been start support PhysX. From Game Smoking part using Fluvio 2.1.0 Multiphasic Simulation smoke effect, Smoke Coordinate based on FDS Simulation. Recent game engine computer graphic developers usually focus on resources visualization smoke and the fire smoke not focus on physically environment. But in the fire simulation, the smoke simulation game or firefighter simulation game part requires a different approach of fire effect model. In this paper, we focus on smoking location boundary and fire model of backdraft. The proposed method can change particles and physics more accurately than other fluid dynamics graphics method approach.

Lightweight wood trusses are economical construction elements that combine high strength, light weight, and cost savings. The parallel-chord truss is one of the most common lightweight trusses used in commercial and residential occupancies today. Like all structural components, these trusses are arguably susceptible to failure when exposed to fire. This paper will address fire resistance concerns of parallel-chord, lightweight wood truss floor- and roof-ceiling assemblies, particularly their performance under fire conditions and their susceptibility to construction defects. Because evaluating the effect of fire exposure on both conventional and lightweight wood truss assemblies is so important, considerable supplemental background information on the standard fire test, as it applies to general types of construction, is also provided.

In order to investigate the gravity current speed and the extent of its mixed region in backdraft experiments, a series of scaled salt water experiments were conducted. The scaling parameters are the Froude number, v* = v/JPgh,, and the normalized density difference, P = (po p,)/p,, where 1 indicates initial conditions in the compartment (fresh) and 0 indicates conditions in the ambient (salt). The scaled compartment (0.3m x 0.15m x 0.15m) was fitted with a variety of end openings: full, slot, door, and window. Video and photo data indicate that the mixing layer which rides on the gravity current in the full opening case, expands to occupy nearly the entire current in the partial opening cases. Results for the scaled current height, h*=h,/h, and v* respectively are: full (0.5, 0.44), slot (0.38, 0.32), door (0.33, 0.35), and window(0.29, 0.22). These data are independent of P and are in good agreement with limit calculations from the literature.

Technology can be a useful tool for security in schools; it can also trigger a backdraft of protest and legal complaints from parents and students raising constitutional law privacy objections. An action that begins with benign motives of student safety, identification, and helping schools and districts to improve their operations can end up in a full-blown federal court legal battle over the law governing individual freedoms.

This study is a qualitative exploration of backdraft phenomena. Backdraft is defined as a rapid deflagration following the introduction of oxygen into a compartment filled with accumulated excess pyrolyzates. A scenario describing the physical and chemical fundamentals underlying backdraft phenomena is presented. A half-scale apparatus, designed to avoid dangerous overpressures, was used to obtain data from backdraft experiments. A gas burner supplied a 150 kW natural gas fire in a 1.2 m high, 1.2 m wide, 2.4 m long compartment with a small, 25 mm high, 0.3 m wide vent to ambient at floor level. Significant unburnt fuel accumulates in 180 seconds, when a hatch covering a 0.4 m high, 1.2 m wide vent, centered on a short wall, is opened, simulating a window breaking due to thermal stresses. The propagation across the compartment of the cold density-driven flow, which enters through the new opening, is called a “gravity current.” This gravity current carries a flammable mixed layer to a spark located near the burner on the opposite wall. The rapid deflagration that results upon ignition of the mixed layer is the backdraft. A compartment fire model is used to calculate conditions in the compartment before the vent opens. The hypothesized scenario appears to be confirmed by the deflagrations and exterior fire balls observed in these preliminary experiments.

The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range (MOR) units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands. Performance assessment included measurement of airflow and sound levels across fan settings and experiments to quantify the contemporaneous capture efficiency for the exhaust generated by natural gas cooking burners.Capture efficiency is defined as the fraction of generated pollutants that are removed through the exhaust and thus not available for inhalation of household occupants. Capture efficiency (CE) was assessed for various configurations of burner use (e.g., single front, single back, combination of one front and one back, oven) and fan speed setting. Measured airflow rates were substantially lower than the levels noted in product literature for many of the units. This shortfall was observed for several units costing in excess of $1000. Capture efficiency varied widely (from

In dieser Arbeit werden konventionell errichtete Gebäude mit Gebäuden, die hoch wärmegedämmt sind und eine hohe Luftdichtheit aufweisen (Gebäude moderner Bauweise), verglichen. Es wird überprüft, ob sich aus dieser modernen Bauweise Nachteile für den Brandschutz ergeben können. Anhand von Bränden in Gebäuden, die sich mit dieser Bauweise vergleichen lassen, werden Probleme beschrieben, die bei der Brandbekämpfung entstanden. Es werden mögliche Ursachen für diese Probleme identifiziert. Da sich die Gebäudetechnik von Gebäuden moderner Bauweise teilweise stark von der in konventionellen Gebäuden unterscheidet, wird diese ausführlich beschrieben und überprüft, wie sie sich hinsichtlich des Brandschutzes auswirkt. Besonders wird hier auf die Lüftungsanlage und die dazugehörigen Überströmöffnungen eingegangen. Die Brandphänomene Flashover, Rollover und Backdraft werden erläutert, und es wird analysiert, ob die moderne Bauweise diese Phänomene begünstigt. Etwaige Gegenmaßnahmen werden erläutert. Die Löschsysteme Fognail® und CCS-Cobra® werden dargestellt und auf ihre Einsatzmöglichkeiten im Bereich von Bränden in Gebäuden moderner Bauweise überprüft. Um Gebäude moderner Bauweise beim Feuerwehreinsatz schnell identifizieren zu können, wurde ein Merkblatt erarbeitet.

In the 1980's, there were a number of unusual arson fires involving very fast fire growth and in some cases premature structural failure. These characteristics posed great risks for fire fighters. The evidence, such as melted steel, indicated that a high temperature accelerant was involved. To support their investigation into these fires, the Seattle Fire Department organized a large scale demonstration. An accelerant with characteristics similar to rocket propellant was used to initiate a fire in a 1900 m 2 room in a single story building. The accelerant produced peak heat fluxes of 250-300 kW/m 2 in approximately five seconds. Approximately two minutes after ignition of the accelerant, there was an apparent backdraft event and then flashover occurred The building was heavily involved within four minutes. From this demonstration, the Seattle Fire Department developed and distributed information to help other fire departments recognize certain characteristics of this type of arson and modify their procedures to protect their personnel.

Glass breaking in compartment fires is an important practical problem since a window acts as a wall before breaking and as a vent after breaking. If sufficient excess pyrolyzates have accumulated in the hot layer, this sudden geometric change can lead to backdraft and flashover. As Emmons explained at the First Symposium, windows break in fires due to thermal stress from the differential heating of the central portion and the shaded edge. The focus of this paper is on quantifying the connection between the compartment fire and the glass temperature to predict the window breaking time, tb. Techniques are presented for accurately calculating the history of the central glass temperature profile, T (x .r), for any fire exposure. Two-dimensional temperature histories, T (x ,y ,t), where x is depth and y is toward the center, and mean stress histories, azz (y ,t), are also calculated. It is determined here that breaking occurs when the mean glass temperature difference is ~T = (ablE ~)g, where ablE is the maximum glass tensile strain, ~ is the thermal coefficient of linear expansion and g is a geometry factorpf order one. Calculations suggest that the edge remains at its initial temperature, T; , so that ~T = T (tb) Ti, when the shading is large, sIL ~2, and the heating is fast, atb Is2::;1, where L is the glass thickness, s is the shaded edge width and «is the glass thermal diffusivity

This paper reports the fire conditions that occurred in a townhouse and the results of software simulations that were performed to provide insight on the peculiar thermal conditions that developed. Fire rescue was called by the occupants of the house when they became aware that smoky conditions were developing on the second floor. Two of the firefighters entered the bedroom where the smoke was originating from and a short time after a flame front invested them while propagating them backward into the stairwell. The post fire investigation determined that the fire started as a consequence of the smoldering combustion of material contained in a wardrobe located adjacent to one of the room walls. A simulation scenario was developed based on the information obtained on the actual building geometry, material thermal properties and the fire behaviour. The calculations that best represented the actual fire conditions indicate that the partial opening of the window and bedroom door provided outside air (oxygen) to a pre-heated, under ventilated fire compartment.

This paper addresses fire and smoke representation for virtual fire scenarios with a rendering tha~ takes inlo account the optical properties of smoke and fire through particle system and fnlzzy blob techniques. A dice-and-mercralgorithm has been developed to establish a bridge between objects generated with advanced 3D systems and Cartesianbased geometries. Thi methodology has been applied to simulate and display backdraft problems using the Fire Dynamics Simulator code developed at NIST.

This document describes the Cold Vacuum Drying Facility (CVDF) instrument air (IA) system that provides instrument quality air to the CVDF. The IA system provides the instrument quality air used in the process, HVAC, and HVAC instruments. The IA system provides the process skids with air to aid in the purging of the annulus of the transport cask. The IA system provides air for the solenoid-operated valves and damper position controls for isolation, volume, and backdraft in the HVAC system. The IA system provides air for monitoring and control of the HVAC system, process instruments, gas-operated valves, and solenoid-operated instruments. The IA system also delivers air for operating hand tools in each of the process bays.

This report presents a detailed description of the phenomena flashover, backdraft and smoke gas explosion. The physical and chemical processes which are involved in these phenomena are thoroughly discussed. The report also describes a number of compartment fire scenarios which are believed to be the most common scenarios occurring in Sweden. The description is based on a number of full- scale experiments which were carried out within the project. At the end of the report, possible warning signs of a potential flashover and backdraft are discussed. In the appendices, a number of models used to predict flashover are evaluated, using data from small scale experiments carried out within the project.

The application of backdraft at the first gilling operation after carding results in significant reduction in percentage noil and an increase in the mean fibre length of the top. These effects depend on the backdraft and direction of feed. Percentage noil is also dependent on backratch but is independent of the faller-bar pinning density. Measurements are also given to show how back-roller force is affected by backdraft, backratch, and the total free space between the pins and the fallers.

The tempered glass is widely used in the buildings because of its good transparence and fire endurance under the protection of the sprinkler. The fire backdraft may occur under the good ventilation condition after the tempered glasses fall apart in fire, which can endanger the human evacuation and fire rescue. By the testing of the surface temperature of the tempered glass exposed to the building fire, the critical temperature of the glass fracture can be acquired and the basis for the prediction and prevention of the fracture of the tempered glass then can be provided, which is useful for the performance-based design of the fire safety. The infrared imaging equipment is firstly used in China for the research on the fire endurance of the tempered glass.

Natural thermosiphoning of solar-heated air is important for many passive solar applications. It is also important to prevent reverse thermosiphoning at night, often with the use of backdraft dampers. Commonly used plastic film dampers may restrict air flow. Therefore, this project developed a novel backdraft damper that utilizes bimetal coils to actuate a conventional metal damper. Two prototype dampers were tested in the upper and lower vents of a thermosiphoning air panel. The upper damper opened fully on sunny days, but partial opening of the lower damper reduced collector efficiency by 19%. A single upper damper should minimize reverse thermosiphoning. Future efforts will study the performance of plastic-film dampers and a single, bimetal-actuated damper in the upper vent.