Download or read book Computational Studies of Parameters Affecting Positive Pressure Ventilation in Compartment Fires and Cold Flow Experiments in a One Room Burn Structure written by Colin McCartney Beal and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Computational Characterization of Strong Vent Flow Enclosure Fires written by Craig George Weinschenk and published by . This book was released on 2011 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: Firefighters often arrive at structures in which the state of fire progression can be described as ventilation-controlled or under-ventilated. This means that inside the enclosure the pyrolyzed fuel has consumed most, if not all of the available oxygen, resulting in incomplete combustion. Under-ventilated (fuel rich) combustion is particularly dangerous to occupants because of the high yield of toxins such as carbon monoxide and to firefighters because once firefighters enter the structure and introduce oxidizer, the environment can rapidly change into a very dangerous, fast burning condition. The fuel load in many compartment fires would support a several megawatt fire if the fire were not ventilation controlled. In the process of making entrance to the fire compartment, firefighters will likely provide additional ventilation paths for the fire and may initiate firefighting tactics like positive pressure ventilation to push the hot flammable combustion products out of the attack pathway. Forced ventilation creates a strongly mixed flow within the fire compartment. Ventilation creates a complex fluid mechanics and combustion environment that is generally not analyzed on the scale of compartment fires. To better understand the complex coupling of these phenomena, compartment scale non-reacting and reacting experiments were conducted. The experiments, which were conducted at The University of Texas at Austin's fire research facility, were designed to gain insight into the effects of ventilation on compartment thermal characteristics. Computational models (low and high order) were used to augment the non-reacting and reacting experimental results. Though computationally expensive, computational fluid dynamics models provided significant detail into the coupling of buoyantly driven fire products with externally applied wind or fan flow. A partially stirred reactor model was used to describe strongly driven fire compartment combustion processes because previously there was not an appropriate low dimensional computational tool applicable to this type of problem. This dissertation will focus on the experimental and computational characterization of strong vent flows on single room enclosure fires.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures written by nist and published by Createspace Independent Publishing Platform. This book was released on 2013-11-22 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of six experiments was conducted in a highrise apartment building in Chicago, Illinois. One experiment on each of the fire floors utilized portable fans and the other utilized a large truck or trailer mounted fan. The two experiments on the third floor examined the effects of wind driven fire conditions. All of the experiments created high temperatures and dense smoke conditions in the hallway. Numerous configurations were used during the experiments and the ability of the fans to keep smoke and heat out of the stairwell was analyzed. The minimum design pressures of NFPA 92A were used as baselines to compare to the actual pressures measured.In this limited set of experiments portable fans and mounted fans were able to quickly clear the stairwell of smoke and maintain a pressure high enough to prevent smoke infiltration into the stairwell. Positive pressure ventilation fans utilized correctly can increase the effectiveness and safety of fire fighters and survivability of occupants in high-rise buildings. When configured properly PPV fans can meet or exceed previously established performance metrics for fixed smoke control systems.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures High Rise Pressure Experiments NISTIR 7412 written by nist and published by . This book was released on 2013-11-21 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: One hundred and sixty experiments were conducted in athirty-story vacant office building in Toledo, Ohio to evaluate the ability of fire department positive pressure ventilation fans to pressurize a stairwell in a high-rise structure in accordance with established performance metrics for fixed stairwell pressurization systems. Variables such as fan size, fan angle, setback distance, number of fans, orientation of fans, number of doors open and location of vents open were varied to examine capability and optimization of each. Fan size varied from 0.4 m (16 in) to 1.2 m (46 in). Fan angle ranged from 90 degrees to 80 degrees. The setback distance went from 0.6 m (2 ft) to 3.6 m (12 ft). Between one and nine fans were used which were located at three different exterior locations and three different interior locations. Fans were oriented both inseries and in parallel configurations. Doors throughout the building were opened and closed to evaluate the effects. Finally a door to the roof and a roof hatch were used as vent points. The measurements taken during the experiments included differential pressure, air temperature, carbon monoxide, metrological data and sound levels.PPV fans utilized correctlycan increase the effectiveness of fire fighters and survivability of occupants in high-rise buildings. In a high-rise building it is possible to increase the pressure of a stairwell to prevent the infiltration of smoke if fire crews configure the fans properly. Although many factors contribute and need to be considered for effective PPV operations, properly configured PPV can achieve stairwell pressures that are high enough to meet or exceed the performance metrics for fixed smoke control systems.
Download or read book Effect of Positive Pressure Ventilation on a Room Fire written by nist and published by Createspace Independent Publishing Platform. This book was released on 2013-11-14 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fire departments use ventilation blowers or fans to pressurize a structure prior to suppressing a fire. This pressurization or positive pressure ventilation (PPV) tactic has not been characterized carefully enough to establish specific guidelines for optimum use of PPV. PPV can assist in the venting of smoke and high temperature combustion products and make attacking the fire easier than without PPV. However, this tactic also provides additional oxygen to the fire and can increase the rate of heat and energy being released. This study examined gas temperatures, gas velocities and total heat release rate in a series of fires in a furnished room. The use of the PPV fan created slightly lower gas temperatures in the fire room and significantly lower gas temperatures in the adjacent corridor. The gas velocities at the window plane were much higher in the PPV case than in the naturally ventilated scenario. This higher velocity improved visibility significantly. PPV caused an increase in heat release rate for 200 s following initiation of ventilation but the heat release rate then declined at a faster rate than that of the naturally ventilated experiment.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures written by U.s. Department of Commerce and published by CreateSpace. This book was released on 2014-01-31 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of experiments was run in a masonry educational building examining the ability of fire service Positive Pressure Ventilation (PPV) fans to limit smoke spread or to remove smoke from areas where potential occupants may be located. The PPV fans are able to accomplish this by creating pressures higher than that of the fire to manage where the smoke and hot gases flowed in the building. Preliminary experiments examined the pressure increase created by portable fans and mounted fans in different configurations and locations. The two main fire scenarios included a long hallway with classrooms and a gymnasium. Both scenarios included fires that produced a large amount of smoke and hot gases, and instrumentation was placed to assess tenability criteria and how PPV tactics can either increase or decrease tenability. Measurements included temperature, pressure, thermal imaging and video views.
Download or read book Evaluation of the Ability of Fire Dynamic Simulator to Simulate Positive Pressure Ventilation in the Laboratory and Practical Scenarios written by nist and published by Createspace Independent Publishing Platform. This book was released on 2013-11-22 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: Positive Pressure Ventilation (PPV) is a tactic that is used on fire grounds across the world everyday, both to improve tenability after the extinguishment of a fire and/or offensively during fire attack to improve firefighting conditions. PPV has proven that it can be a useful tool on the fire ground, but it can also kill or injure fire fighters and civilians if used improperly. Data from three full-scale experiments are compared with simulations completed with the computational fluid dynamic model Fire Dynamic Simulator (FDS). The full-scale experiments characterize a Positive Pressure Ventilation (PPV) fan in an open atmosphere, in a simple room geometry and in a room fire. All experiments qualify and quantify the comparison of the experimental results with the FDS results. A concluding scenario is modeled utilizing the calibration of the full-scale experiments to examine the effects of PPV on a fire in a two-story, colonial style house.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures written by Stephen Kerber and published by . This book was released on 2007 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: PPV fans utilized correctly can increase the effectiveness of fire fighters and survivability of occupants in high-rise buildings. In a high-rise building it is possible to increase the pressure of a stairwell to prevent the infiltration of smoke if fire crews configure the fans properly. Although many factors contribute and need to be considered for effective PPV operations, properly configured PPV can achieve stairwell pressures that are high enough to meet or exceed the performance metrics for fixed smoke control systems.
Download or read book NIST GCR 12 968 written by U.s. Department of Commerce and published by CreateSpace. This book was released on 2014-04-28 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation involves computational validation of non-reacting and reacting flow simulations in a modeled room scale burn facility to quantified experiments conducted in the actual room scale facility on The University of Texas-Austin's campus. This chapter provides background and motivation for the work discussed in greater detail in the following chapters.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures written by Stephen Kerber and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the limited series of experiments in the long hallways of this masonry educational building, the use of positive pressure ventilation to increase pressure to reduce temperatures, limit smoke spread and increase visibility was effective. This series of experiments demonstrated that fire service positive pressure ventilation fans can be used successfully in large structures to increase tenability of potential victims and improve conditions for firefighting crews.
Download or read book Evaluating Positive Pressure Ventilation in Large Structures written by Stephen Kerber and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: PPV fans utilized correctly can increase the effectiveness of fire fighters and survivability of occupants in high-rise buildings. In a high-rise building it is possible to increase the pressure of a stairwell to prevent the infiltration of smoke if fire crews configure the fans properly. Although many factors contribute and need to be considered for effective PPV operations, properly configured PPV can achieve stairwell pressures that are high enough to meet or exceed the performance metrics for fixed smoke control systems.
Download or read book Evaluating positive pressure ventilation in large structures written by Stephen Kerber and published by . This book was released on 2007 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Data for Room Fire Model Comparisons written by Richard D. Peacock and published by DIANE Publishing. This book was released on 1993-12 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents the types of analyses that can be used to examine large-scale room fire test data to prepare the data for comparison with zone-based fire models. The base of experimental data ranges in complexity from one room tests with individual furniture items to a series of tests conducted in a multiple story hotel equipped with a zoned smoke control system. Graphs and diagrams.
Download or read book Probabilistic Models for the Behavior of Compartment Fires written by Nathan O. Siu and published by . This book was released on 1981 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fire ventilation written by Stefan Svensson and published by . This book was released on 2005 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Positive Pressure Ventilation on a Room Fire written by S. Kerber and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterizing Positive Pressure Ventilation Using Computational Fluid Dynamics written by S. I. Kerber and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
