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Zacharoff, Hugo. "Simulating cable fires in Fire Dynamics Simulator : Based on small scale testing in cone calorimeter." Thesis, Luleå tekniska universitet, Byggkonstruktion och brand, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-85995.
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In a society increasingly more influenced by technology and electricity, electrical and computer cables will play a more vital role in humans’ everyday life. With an increasing number of cables being introduced into society, the risk of fires caused by or involving cables will increase and become a more common danger to property and human lives. The fire properties of cables are tested according to Standard EN 50399 where vertically mounted cables are exposed to a burner for 20 minutes. The present work consists of running simulations imitating the conditions of Standard EN 50399 for testing cables using a Computational Fluid Dynamics program called Fire Dynamic Simulator (FDS). The general idea was to test the material in small-scale and running simulations to verify how well simulated values corresponded to values from actual testing, providing a potential less costly method of predicting the correct Euroclass in the development phase of new cables. During a visit at RISE in Borås, material for testing and a script previously used for testing a module of EN 50399 in FDS were obtained from previous work. The FDS script was later altered by adjusting the meshes inside the model in an effort to reduce simulation time. This was done by prioritizing smaller grid cells in high activity areas and using large grid cells in low activity areas. To verify the function of the model on the current version 7.5.0 of the FDS software, simulations were run empty without modelling the cables. To validate the FDS-model, temperatures were measured at four heights using a resemble of plate thermometers and the results were compared to older temperature measurements from an actual experiment using plate thermometers in the apparatus used at RISE when testing in the EN 50399 apparatus. To obtain the material data necessary for FDS, the material used as cable sheeting (surrounding the conductive metal core) molded into thin square plates were tested using a cone calorimeter at Luleå University of Technology. Two tests were conducted at irradiance levels of 50 and 25 kW/m2 where heat release rate was measured. Thenceforth followed 14 repeated tests at varying irradiance levels with the sole purpose of measuring time to ignition. In total 16 experiments were conducted, of which ten resulted in ignition, four of which did not ignite after exposure for 20 minutes and two which were interrupted due to swelling of the sample. After testing in the cone calorimeter, a critical irradiance level and ignition temperature of the material were verified using a theory presented by Janssens (1991). Two ramps – a controlled way of determining the materials heat release over time in FDS – were created based on the two tests at different irradiance levels. Using these new parameters simulations recreating the scenario for testing according to EN 50399 were run using FDS. Three simulations were run, testing different ramps and different implementations of the cables. The results proved it difficult to achieve the same heat release rate for cables simulated using FDS as heat released rate measured at experiments. With the simulations results at hand, in combination with uncertainties regarding material data it became clear the material had proven more difficult then anticipated. A possible reason for the big gap in heat release rate between simulations and experimental values could be considered to be the high ignition temperature given as material input for the cable in FDS.
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Schagerström, Lukas. "Valideringsstudie av Multi-Zone Fire Model." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-78682.
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Det finns ett flertal brandsimuleringsprogram på marknaden som används i olika utsträckning varav ett är Fire Dynamics Simulator (FDS). En av nackdelarna med FDS är att det kan ta mycket tid att göra en brandsimulering. Det finns brandsimuleringsprogram som med stor sannolikhet utför brandsimuleringar snabbare än FDS. För några av dessa brandsimuleringsprogram finns det inte någon dokumentation om hur resultaten som brandsimuleringsprogrammen producerar ställer sig mot det som skulle hända i verkligheten vid en brand, något som kallas att vara valideratdet vill säga programmen är inte validerade. Ett av dessa brandsimuleringsprogram är Multi-Zone Fire Model (MZ-Fire Model). Brandsimuleringsprogrammet MZ-Fire Model bygger på ett multizonkoncept framtaget av Suzuki et al. Multizonkonceptet har validerats i tidigare studier varav ett är en brand i tunnel men även bränder i mindre lokaler har prövats. Det finns utrymme för ökad kunskap om hur multizonkonceptet hanterar bränder i stora rumslokaler då det inte finns någon känd dokumentation kring detta. Det finns i dagsläget inte en enda studie som behandlar brandsimuleringsprogrammet MZ-Fire Model. I rapporten redogörs för simulerande av en brand i 4 olika rum av brandsimuleringsprogrammen MZ-Fire Model och FDS, dess simulerade värden är sedan jämförda mot varandra.There are a number of fire simulation programs on the market that are used to varying degrees, one of which is Fire Dynamics Simulator (FDS). One of the disadvantages of FDS is that it can take a lot of time to do a fire simulation. There are fire simulation programs that are very likely to perform fire simulations faster than FDS. For some of these fire simulation programs, there is no documentation on how the results produced by the programs compare with what would happen in the event of a real fire, something called to bethat is they are not validated. One of these fire simulation programs is Multi-Zone Fire Model (MZ-Fire Model). The fire simulation program MZ-Fire Model is based on a multi-zone concept developed by Suzuki et al. The multi-zone concept has been validated in previous studies, one of which is a fire in a tunnel but fires in smaller premises have also been tested. There is room for increased knowledge about how the multi-zone concept handles fires in large rooms, as there is no known documentation on this. Currently, there is not a single study dealing with the MZ-Fire Model program. The report describes the simulation of a fire in 4 different rooms by the programs MZ-Fire Model and FDS, its simulated values are then compared against each other.
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Clement, Jason Mark. "Experimental verification of the Fire dynamics simulator (FDS) hydrodynamic model." Thesis, University of Canterbury. Civil Engineering, 2000. http://hdl.handle.net/10092/5857.
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The objective of this research has been to verify the hydrodynamic model that is contained within the Fire Dynamics Simulator (FDS). In the first part of the research, a series of buoyant salt water experiments have been conducted, with the purpose of generating experimental data for comparison with computational fluid dynamics (CFD) models. Two types of buoyant flows have been generated in the experiments; a natural transitional flow, and flows that resemble fire induced smoke flow within a residential building. Laser Induced dye Fluorescence (LIF) has been used to measure the fluid density in a single vertical plane of the flow. Measurements have also been made of eddy frequencies on the perimeter of the transitional flows, and of the temporal development of the fire similar flow fields. The uncertainty of the experimental measurements has been quantified. In the second part of the research, the salt water experiments have been simulated with the FDS, to assess the accuracy of the hydrodynamic model. The simulations of the transitional flows are found to be highly dependent upon the resolution of the computational grid. The findings highlight the fact that the numerical methods employed in the FDS can generate fluid behaviour in the computational flow field that does not occur in the real salt water flows. This "numerical fluid behaviour" is clearly seen in the transitional flow computations, because at the source of the flow, the buoyancy and the momentum of the fluid are orientated in perpendicular directions to each other. The comparison of the computational and experimental results for the transitional flows show that the trajectory of the computed buoyant plume is steeper than the trajectory of the real salt water plume. It is speculated that the disagreement in the plume trajectory may be due to the spatial distribution of pressure within the computational domain. Due to limited computational facilities, this research has been unable to determine if the FDS hydrodynamic model can accurately compute the natural transition to turbulence. Further simulations of the transitional flows are required with grid cell dimensions that are less than the compartment height divided by 100, to determine if the transition can be correctly computed. The simulations of the fire similar flows have shown, that the FDS performs well in modelling fully turbulent flow fields, as found in residential building fires. From the fire similar flow simulations a maximum grid cell dimension, of the compartment height divided by 50, has been recommended for the simulation fire induced smoke flows within multicompartment residential scale buildings. At this recommended resolution, and resolutions coarser than this, the Smagorinsky sub-grid scale (SGS) has been found to give more accurate results than the constant viscosity SGS model. A relationship has been determined, for the minimum fluid viscosity that is required for stable computations in simulations that use the constant viscosity SGS model.
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Webb, Alex K. "FDS modelling of hot smoke testing, cinema and airport concourse." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-120606-181621/.
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Acevedo, Muñoz Luis. "A novel approach to reduce fire exposure and promote nature conservation in Mediterranean ecosystems: the case study of Reserva Natural da Serra da Malcata, Portugal." Master's thesis, ISA-UL, 2016. http://hdl.handle.net/10400.5/12176.
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Mestrado Mediterranean Forestry and Natural Resources Management - Instituto Superior de Agronomia - ULIn Portugal, wildfires represent a major concern that yearly produces numerous economic and environmental losses. Currently, there is a continuous increase of biomass accumulation which increases wildfire risk into Mediterranean protected areas due to lack of management. An example is the protected area of Serra da Malcata, where prescribed burning has been implemented. However, fuel treatments implementation within preserved areas remains quasi forbidden in the major cases. The main objective is to develop and asses a novel approach to reduce fire exposure and simultaneously promote conservation habitat within Natura 2000 Habitats of Reserva Natural da Serra Malcata. For this aim, fire exposure assessment of three different fuel management scenarios: current situation, planned treatments and low intense treatments within Habitat Natura 2000 promoting conservation goals, were done by using burn probability modelling under extreme conditions for 24h burn period. Results showed similar performance of conservation enhancement scenario if compare with planned treatment scenario. Nevertheless, biggest fire exposure reductions were observed within Natura 2000 network. Limitations and assumptions derived from input parameters, model validation or fire simulator could affect fire exposure results. However, results open the debate to include fuel treatments within protected areas for achieving medium- and long-term fire risk reduction
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Kim, Mihyun Esther. "A study on pulsation in Runehamar Tunnel fire tests with forced longitudinal ventilation." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-100506-112551/.
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Thesis (M.S.) -- Worcester Polytechnic Institute.Keywords: pulsation; FDS; fire dynamics simulator; oscillation; fluctuation; tunnel fire; forced ventilation. Includes bibliographical references (p.65-66).
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Wagner, Denis M. Jr. "Training effectiveness study of simulator usage and its impact on live Fire Armor Gunnery." Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/42749.
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Approved for public release; distribution is unlimitedIt is mandatory for tank commanders and gunners to train in the Advanced Gunnery Training System (AGTS), but the effectiveness of conducting this training is unclear. Although anecdotal evidence suggests that training transfer may be occurring, previous research could not definitively prove that training transfer is occurring between the simulator and the performance during live fire gunnery qualification. The purpose of this study was to assess whether there was a correlation between performance in the AGTS and modified live fire gunnery. Sixty-five participants from the Army Armor School volunteered for this study. Data was collected on their AGTS and live fire performance. Results indicated there was no significant correlation between performance in the AGTS and on the modified live fire gunnery. Exploratory analyses showed those who had completed the AGTS Gate to Live Fire performed better on the modified live fire gunnery than those who had not completed the AGTS training. This result suggests that training transfer may be occurring. Given that specific metrics are identified and incorporated into the AGTS, there is strong potential for simulation training to allow individuals to attain a higher level of proficiency than would be attained by just live training.
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Kerber, Stephen. "Evaluation of the ability of fire dynamic simulator to simulate positive pressure ventilation in the laboratory and practical scenarios." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3243.
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Thesis (M.S.) -- University of Maryland, College Park, 2005.Thesis research directed by: Dept. of Fire Protection Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Parkes, Anthony Richard. "The impact of size and location of pool fires on compartment fire behaviour." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2009. http://hdl.handle.net/10092/3444.
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An understanding of compartment fire behaviour is important for fire protection
engineers. For design purposes, whether to use a prescriptive code or performance
based design, life safety and property protection issues are required to be assessed. The
use of design fires in computer modelling is the general method to determine fire safety.
However these computer models are generally limited to the input of one design fire,
with consideration of the complex interaction between fuel packages and the
compartment environment being simplified. Of particular interest is the Heat Release
Rate, HRR, as this is the commonly prescribed design parameter for fire modelling. If
the HRR is not accurate then it can be subsequently argued that the design scenario may
be flawed. Therefore the selection of the most appropriate fire design scenario is
critical, and an increased level of understanding of compartment behaviour is an
invaluable aid to fire engineering assumptions.
This thesis details an experimental study to enhance the understanding of the impact and
interaction that the size and location of pool fires within an enclosure have upon the
compartment fire behaviour. Thirty four experiments were conducted in a reduced scale
compartment (½ height) with dimensions of 3.6m long by 2.4m wide by 1.2m high
using five typical ventilation geometries (fully open, soffit, door, window and small
window). Heptane pool fires were used, located in permutations of three evenly
distributed locations within the compartment (rear, centre and front) as well as larger
equivalent area pans located only in the centre. This thesis describes the experimental
development, setup and results of the experimental study. To assist in the classification
of compartment fire behaviour during the experiments, a ‘phi’ meter was developed to
measure the time dependent equivalence ratio. The phi meter was developed and
configured to measure O₂, CO₂ and CO. The background development, calibration, and
experimental results are reported. A review of compartment fire modelling using Fire
Dynamics Simulator, has also been completed and the results discussed.
The results of this experimental study were found to have significant implications for
Fire Safety Engineering in that the size of the fire is not as significant as the location of
the fire. The effect of a fire near the vent opening was found to have a significant impact
on compartment fire behaviour with the vent located fuel source increasing the total
compartment heat release rate by a factor of 1.7 to that of a centrally placed pool fire of
the same total fuel area. The assumption that a fire located in the centre of the room
provides for the highest heat release rate is not valid for post-flashover compartment
fires. The phi meter was found to provide good agreement with the equivalence ratio
calculated from total compartment mass loss rates, and the results of FDS modelling
indicate that the use of the model in its current form can not be applied to complex pool
fire geometries.
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Pau, Dennis Su Wee. "A Comparative Study on Combustion Behaviours of Polyurethane Foams with Numerical Simulations using Pyrolysis Models." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2013. http://hdl.handle.net/10092/9177.
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This research investigates the decomposition and burning behaviours of polyurethane foams experimentally and compares the experimental results obtained with the numerical results from the pyrolysis model of Fire Dynamics Simulator, Version 5 (FDS 5). Based on the comparison of model and experimental heat release rates, the accuracy of the pyrolysis model is quantified. In total, this research tested seven polyurethane foams consisting of three non-fire retardant (NFR) and four fire
retardant (FR) foams. According to the simultaneous differential scanning calorimetry and thermogravimetric analysis (SDT) experiments, the decomposition behaviour of polyurethane foams under nitrogen environment is represented by two pyrolysis
reactions. The first reaction consists of foam decomposition into melts and gases while the second reaction consists of the decomposition of the remaining melts into gases.
The kinetic properties which govern the rate of decomposition are the activation energy (E), pre-exponential factor (A), reaction order (n) and heat of reaction (Δhr). Using graphical techniques, E, A and n of the first and second reactions are
determined from the thermogravimetric analysis (TGA) results. Through analysing the differential scanning calorimetry (DSC) results, Δhr is determined from the changes in heat flow and sample mass. The thermophysical properties govern the heat
transfer through material and these are the thermal conductivity (λ) and specific heat (cp) which are measured experimentally at ambient temperature through the Hot Disk method.
Through the Sample Feeding Vertical Cone, the decomposition and melting behaviours of polyurethane foams in a vertical orientation are investigated and the foams tested can be categorised into those which produce melts only after ignition and
those which produce melts and char after ignition. The 1-dimensional burning behaviour of foams is obtained from the cone calorimeter experiments. The NFR foams show a change from plateau burning behaviour at low heat flux to two stage burning behaviour at high heat flux while the FR foams consistently show two stage burning behaviour. The combustion property governs the amount of heat released when fuel combusts and this is the effective heat of combustion (Δhc,eff) which is determined from the heat released and mass consumed in the cone experiment.
The 1-dimensional burning behaviour is simulated using the pyrolysis model of FDS 5 and two different modelling approaches are considered. The direct method uses the material properties determined experimentally as FDS 5 inputs while the refined
method uses the genetic algorithm of Gpyro to refine the kinetic properties which are later used as FDS 5 inputs. The heat release rate of the model and experiment are compared through linear regression analysis which quantifies the accuracy of both
methods. The accuracy is defined as the percentage of data points within the boundary of acceptance which is bounded by 25 % of the greatest experimental heat release rate. This assessment method places greater emphasis on the accuracy of developed burning phases and lesser emphasis on the accuracy of initial growth and final decay. The accuracy of the direct method is found to be 56 % while the refined method with
estimated kinetic properties achieves a higher accuracy of 75 %.
The 2-dimensional burning behaviours are investigated in the foam slab experiments for two different slab thicknesses, 120 and 100 mm. The opposed-flow spread of 120 mm slab is more intense and rapid while for the 100 mm slab, the flame spread is less intense and slow. FDS 5 is used to simulate the experimental results but when the material properties either developed experimentally or refined by Gpyro are used as inputs, the model fails to produce flame spread. This is because FDS 5 does not yet
have the features which address the dynamics of foam melting and the reactive nature of the flame. In order to produce flame spread in the model, E of the reactions have been reduced to increase the decomposition rate.
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Celik, Alper. "Experimental And Numerical Studies On Fire In Tunnels." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613857/index.pdf.
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Fire is a complex phenomenon including many parameters. The nature of fire makes it a very dangerous and hazardous. For many reasons the number of tunnels are increasing on earth and fire safety is one of the major problem related to tunnels. This makes important to predict and understand the behavior of fire, i.e., heat release rate, smoke movement, ventilation effect etc. The literature includes many experimental and numerical analyses for different conditions for tunnel fires. This study investigates pool fire of three different fuel sources: ethanol, gasoline and their mixture for different ventilation conditions, different geometries and different amounts. Combustion gases and the burning rates of the fuel sources are measured and analyzed. The numerical simulation of the cases is done with Fire Dynamics Simulator (FDS), a CFD code developed by NIST.
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Rajput, Prafulla. "A Model of the Emission and Dispersion of Pollutants From a Prescribed Forest Fire in a Typical Eastern Oak Forest." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1283532162.
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Bando, Takashi. "Development for Farsite Fire Growth Simulation for fhe Hardwood Forest in South Eastern Ohio." Ohio University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1243901740.
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Musluoglu, Eren. "A Theoretical Analysis Of Fire Development And Flame Spread In Underground Trains." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610860/index.pdf.
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The fire development and flame spread in the railway carriages are investigated by performing a set of simulations using a widely accepted simulation software called ‘
Fire Dynamics Simulator&
#8217
. Two different rolling stock models
representing a train made up of physically separated carriages, and a 4-car train with open wide gangways
have been built to examine the effects of train geometry on fire development and smoke spread within the trains. The simulations incorporate two different ignition sources
a small size arson fire, and a severe baggage fire incident. The simulations have been performed incorporating variations of parameters including tunnel geometry, ventilation and evacuation strategies, and combustible material properties. The predictions of flame spread within the rolling stock and values of the peak heat release rates are reported for the simulated incident cases. In addition, for a set of base cases the onboard conditions are discussed and compared against the tenability criteria given by the international standards. The predictions of heat release rate and the onboard conditions from the Fire Dynamics Simulator case studies have been checked against the empirical methods such as Duggan&
#8217
s method and other simulation softwares such as CFAST program.
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Meunders, Andreas [Verfasser]. "A study on buoyancy-driven flows: Using particle image velocimetry for validating the Fire Dynamics Simulator / Andreas Meunders." Wuppertal : Universitätsbibliothek Wuppertal, 2016. http://d-nb.info/1120340047/34.
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Clark, Michael M. "Development and Evaluation of a Sub-Grid Combustion Model for a Landscape Scale 3-D Wildland Fire Simulator." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2446.pdf.
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Bova, Anthony Scott. "Modeling the Ventilation of Natural Animal Shelters in Wildland Fires." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274966386.
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Fonseca, Gonçalo Vidal Brejo. "Modelação da espacialização do módulo de fogo no simulador regional SIMPLOT." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4144.
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Saladino, Dario. "Advances in the modeling of fire development in passive houses." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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One of the greatest challenges the world is facing is climate change. According to the Energy Performance of Buildings Directive (EPBD 2010/31/EU), the construction of passive houses, thanks to their characteristics of airtightness and thermal insulation, is a way to reduce pollution and to increase energy efficiency.
However, the airtightness induces new fire risks since it prevents the hot fumes of a fire inside the building from flowing out, leading to a pressure increase inside the house. It must be remembered that 130 Pa is the threshold value of pressure at which the occupants might have difficulties in opening an inward-opening door, remaining trapped inside the house and exposed to the toxic and hot fumes, as well as to the flames.
Researches aimed at evaluating the behaviour of passive houses in case of an internal fire are carried out at the University of Mons; the present thesis represents a contribution to these researches.
A total of twenty-one full-scale experiments was conducted in a 70 m3 two-room building and two fire experiments were also performed outdoors. In all tests, poolfires of n-heptane were considered. Firstly, it was studied how the internal pressure is influenced by: different configurations of the doors, different areas of the poolfire, and safety measures, i.g. the opening of pressure relief vents or shutdown of the ventilation fan.
The trend over time of the HRR, of several internal temperatures, of the pressure in the rooms, of the flow rate in the ventilation system, and of the gas concentrations was determined, verifying also the repeatability of the tests.
Secondly, a mathematical model aimed at reproducing the tests was built inside FDS, allowing to compare the results of the simulations with the experimental ones. The comparison was largely satisfactory and, where differences were evident in the trend of the parameters, it was possible to find out their causes and to suggest ways to improve the accuracy of the modeled results.
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Lindqvist, Petter. "Validering av solida temperaturer i FDS genom jämförelse mot FE-beräkningar." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79973.
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FDS (Fire Dynamics Simulator) använder en version av Navier-Stokes ekvationerna för att göra noggranna beräkningar av värme- och gastransport genom brandbelastade utrymmen. Utvecklarna av programmet arbetar kontinuerligt med att validera det allteftersom nya funktioner tillförs för att öka noggrannheten och bredda tillämpningsområdena. Väldigt lite av detta arbete fokuserar dock på FDS:s konduktionsmodell, den endimensionella Crank-Nicolson metoden. Det här examensarbetet ämnar därför undersöka noggrannheten i FDS:s konduktionsmodell genom jämförelse mot beräkningar med FEM (Finita elementmetoden). En FDS-modell skapades för att tillåta undersökning av en vägg och dess randvillkor med så liten påverkan från andra faktorer som möjligt. Detta för att skapa en kontrollerad omgivning som enkelt kunde replikeras i efterföljande FE-beräkningar av det konduktiva värmeflödet genom den solida obstruktionen. Tre väggar (10 cm betong, 20 cm betong och 1 mm stål) vardera med tre randvillkor (Exposed, Void och Insulated) utsattes för tre temperaturer (100 °C, 500 °C och 1000 °C) vilket ger 27 FDS simuleringar. Den adiabatiska yttemperaturen mättes i varje simulering och användes som indata till motsvarande FE-beräkningar. Resultatet påvisade inga signifikanta motsägelser vad gäller randvillkoren, med tillräcklig tid för termisk penetrering påverkade de den resulterande temperaturen som väntat. Undantaget var en mindre avvikelse i stålväggarna som utsattes för 100 °C och 500 °C med randvillkoren Exposed och Void där FDS aningen underskattade temperaturen relativt FE-beräkningarna. Gastemperaturerna i gridcellerna närmast väggen visade sig vara opålitliga. De tenderade att genomgå substantiella fluktuationer, troligen som ett resultat av hur FDS hanterar diskretiseringen av icke-solida volymer för Navier-Stokes beräkningarna. Dessa fluktuationer påverkade dock inte de resulterande solida temperaturerna eftersom medelgastemperaturen var korrekt. FDS påvisades även ha en tendens att aningen överskatta yttemperaturen under de första minuterna av simuleringarna relativt FE-beräkningarna. Temperaturerna från de två beräkningsmetoderna konvergerade dock efter några få minuter i samtliga tester. Dessa avvikelser ansågs ha för liten påverkan på de solida temperaturerna för att påvisa onoggrannhet i FDS. Därmed drogs slutsatsen att FDS:s beräkningar av temperaturer i solida material är tillräckligt noggranna inom dessa avgränsningar.FDS (Fire Dynamics Simulator) uses a version of the Navier-Stokes equations to make accurate calculations of heat and gas flow through enclosures exposed to fire. The developers of FDS have, and continue to, validate it as new features get added in an attempt to increase its accuracy and broaden its potential applications. However, little of this effort is focused on FDS’ conductive heat transfer model, based on the one-dimensional Crank-Nicolson method. Thus, this study aims to test the accuracy of FDS’ conduction model by comparing it to calculations using FEM (Finite Element Method). FDS simulations were created so as to facilitate the study of a wall and its boundary conditions with as little interference from other factors as possible. This to create a controlled environment which easily could be replicated in the subsequent FE-calculations of the conductive heat flow through the solid obstructions. Three different walls (10 cm concrete, 20 cm concrete and 1 mm steel), each with the three different boundary conditions for the rear surface (Exposed, Void and Insulated), were exposed to three different temperatures (100 °C, 500 °C and 1000 °C) for a total of 27 FDS simulations. The adiabatic surface temperature was measured in each simulation in FDS and used as input for the corresponding FE-calculations. The results showed no clear inconsistencies in the boundary conditions, given enough time for thermal penetration they affected the resulting temperatures as expected. Save a slight deviation in the steel walls exposed to 100 °C and 500 °C with boundary conditions Exposed and Void where FDS slightly underestimated the temperature relative to the FE-calculations. The gas temperatures in the grid cells closest to the wall were found to be unreliable as they tended to undergo substantial fluctuations, likely as a result of how FDS handles the discretization of non-solid space for the Navier-Stokes calculations. These fluctuations were however not found to affect the solid temperatures as the mean gas temperature was accurate. FDS was also found to have a tendency to slightly overestimate the surface temperature in the first few minutes of the simulations relative to the FE-calculations. Though the resulting temperatures from the two methods converged after a few minutes at most in all tests. These deviations were considered to have too minor an impact on the solid temperature to justify claims of inaccuracy in FDS. Thus, the general conclusion of this study is that FDS’ predictions of solid phase temperatures are sufficiently accurate within these delimitations.
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White, Benjamin Leonardo Alves. "Incêndios florestais no Parque Nacional Serra de Itabaiana - Sergipe." Universidade Federal de Sergipe, 2010. https://ri.ufs.br/handle/riufs/4175.
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This research was developed with the objective to determine the forest fire danger index that is the most efficient to predict forest fire inside the National Park Serra de Itabaiana . It also simulates the characteristics of the fire inside each type of vegetation, in order to characterize the risk in each situation. To simulate the forest fires, was used the program BEHAVEPLUS 4.0 . With the proper environmental information, this software can calculate the fire characteristics. The input variables measured in this work were: total amount and humidity content of the fuel; fuel model; mid flame wind speed; and slope steepness. By the results simulated, the vegetations of White Sands had greater flame length (2m), greater Fireline Intensity (1186kW/m), and greater Heat per Unit Area (9628Kj/m2). The Grasses Fields presented the biggest Surface Rate of Spread (12,3m/min), however in the Closed Forests, the simulated fires presented lesser intensity and, consequently, more easily controlled. In order to search for the best forest fire danger index for the Sergipe state and for the National Park Serra de Itabaiana , the values of the five most important indices, cited in literature, were submitted to Pearson s test of correlation and to the Skill Score test. In accordance with the results, the Angstron index was the most efficient to forecast the occurrence of heat points inside Sergipe, as well as to
forecast forest fires inside the National Park. The present work also elaborated a forest fire risk calendar of occurrence, on the basis of the daily precipitation in Itabaiana city, and on
the basis of the historical register of fire occurrences in the National Park. The precipitation demonstrated to have a significant correlation with the fire register, however,
the months that presented lesser rainfall, between 1999 to 2009 (November and December), was not the months with the biggest fire register. In accordance with the
unconditional probability, based in the fire register between 1991 to 2009, the month of February presented greater forest fire probability of occurrence.Esta pesquisa foi desenvolvida com objetivo de buscar um índice de perigo de ocorrência de incêndios florestais que seja eficiente na previsão de incêndios dentro do Parque Nacional Serra de Itabaiana, como também de simular as características do fogo dentro de cada tipo de vegetação (fitofisionomia), a fim de caracterizar o risco que ele possa oferecer em determinada situação. Para simular os incêndios, foi utilizado o programa BEHAVEPLUS 4.0 , que gera uma planilha de dados na qual devem ser preenchidas as variáveis de entrada para se obter as variáveis de saída. Dentre as variáveis de entrada, medidas neste trabalho, estão: a quantidade e o teor de umidade do material combustível, modelo do material combustível, velocidade do vento na altura das chamas e a inclinação do terreno. Com base nos resultados obtidos, a fitofisionomia das Areias Brancas apresentou, de acordo com a simulação, maior altura das chamas (2m), maior Intensidade da linha do fogo (1186kW/m), e maior Energia Calorífera por Unidade de Área (9628Kj/m2). A fitofisionomia dos Campos Graminosos apresentou a maior Velocidade Máxima de Propagação (12,3m/min), já nas Matas, os incêndios simulados foram os de menor intensidade e, conseqüentemente, de mais fácil controle. Para buscar o melhor índice de perigo de ocorrência tanto para o estado de Sergipe quanto para o PARNA Serra de Itabaiana, os valores dos cinco principais índices encontrados na literatura foram submetidos ao teste de correlação de Pearson e ao teste Skill Score. De acordo com os resultados obtidos, o índice de Angstron foi o mais eficiente na previsão de ocorrência de focos de calor dentro do estado de Sergipe, como também na previsão de incêndios florestais dentro do PARNA. O presente trabalho também buscou a elaboração de um calendário de perigo de ocorrência de incêndios florestais com base na precipitação diária no município de Itabaiana e com base no registro histórico das ocorrências de incêndios dentro do PARNA. A precipitação demonstrou ter uma correlação significativa com o registro de incêndios, entretanto, os meses de Novembro e Dezembro, que apresentaram os menores índices de precipitação entre 1999 e 2009, não foram os meses com maior registro de incêndios. De acordo com a probabilidade incondicional, baseada no registro de incêndios de 1991 a 2009, o mês de Fevereiro é o que apresenta maior probabilidade de ocorrência de incêndio florestal dentro do Parque Nacional Serra de Itabaiana.
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Zappone, Marco. "Computational Fluodynamics Modeling (CFD) of horizontal propane jet fires." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textAbstract:
With regard to pipeline transportation of hazardous material, the occurrence of a jet fire is one of the most common accidents in case of loss of containment. In light of this consideration, an appropriate estimation of the accident scenario is necessary to determine the magnitude of the risk and the required measures to avoid or mitigate the consequences. Computational Fluid Dynamics (CFD) represents a valid tool to be used in this framework, because of its capability to describe the evolution of the accident, considering the obstacles and the site-specific factors. In this work, the capability of FLACS CFD code to simulate a propane horizontal jet fire is analyzed and the code is validated against experimental data. The parameters used for the validation are the jet fire geometrical characteristics and the flame temperature. The assessment is performed comparing different numerical models available in FLACS code in order to define the most appropriate to describe horizontal jet-fires. Then, the accuracy of simulation results is assessed using statistical performance metric parameters. In conclusion, results show that the FLACS CFD code is able to describe the horizontal jet fire phenomena in good accordance with experimental data, even though with a slight overprediction. On this basis, an initial study of the model proposed to simulate horizontal jet fire impingement on a pipe is conducted, and the possibility to use Fire Dynamics Simulator (FDS) CFD code to simulate horizontal jet fire is explored.
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Brakeall, John. "Wildfire Assessment Using FARSITE Fire Modeling: A Case Study in the Chihuahua Desert of Mexico." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/923.
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The Chihuahua desert is one of the most biologically diverse ecosystems in the world, but suffers serious degradation because of changes in fire regimes resulting in large catastrophic fires. My study was conducted in the Sierra La Mojonera (SLM) natural protected area in Mexico. The purpose of this study was to implement the use of FARSITE fire modeling as a fire management tool to develop an integrated fire management plan at SLM.
Firebreaks proved to detain 100% of wildfire outbreaks. The rosetophilous scrub experienced the fastest rate of fire spread and lowland creosote bush scrub experienced the slowest rate of fire spread. March experienced the fastest rate of fire spread, while September experienced the slowest rate of fire spread. The results of my study provide a tool for wildfire management through the use geospatial technologies and, in particular, FARSITE fire modeling in SLM and Mexico.
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Smith, Daniel Robert. "Soil respiration in a fire scar chronosequence of Canadian boreal jack pine forest." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/8268.
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This research investigates soil respiration (Rs) in a boreal jack pine (Pinus banksiana Lamb.) fire scar chronosequence at Sharpsand Creek, Ontario, Canada. During two field campaigns in 2006 and 2007, Rs was measured in a chronosequence of fire scars in the range 0 to 59 years since fire. Mean Rs adjusted for soil temperature (Ts) and soil moisture (Ms) (Rs T,M) ranged from 0.56 μmol CO2/m2/s (32 years post fire) to 8.18 μmol CO2/m2/s (58 years post fire). Coefficient of variation (CV) of Rs adjusted for Ts and Ms ranged from 20% (16 years post fire) to 56% (58 years post fire). Across the field site, there was a significant exponential relationship between Rs adjusted for soil organic carbon (Cs) and Ts (P = 1.24*10-06; Q10 = 2.21) but no effect of Ms on Rs adjusted for Cs and Ts for the range 0.21 to 0.77 volumetric Ms (P = 0.702). Rs T,M significantly (P = 0.030) decreased after burning mature forest, though no significant (P > 0.1) difference could be detected between recently burned and unburned young forest. Rs was measured in recently burned boreal jack pine fire scar age categories that differed in their burn history and there was a significant difference in Rs T,M between previously 32 v 16 year old (P = 0.000) and previously 32 v 59 year old (P = 0.044) scars. There was a strong significant exponential increase in S R T,M with time since fire (r2 = 0.999; P = 0.006) for the chronosequence 0, 16 and 59 years post fire, and for all these age categories, Rs T,M was significantly different from one another (P < 0.05). The Joint UK Land Environment Simulator (JULES) was used to model vegetation re-growth over successional time at Sharpsand Creek, though it appeared to perform poorly in simulating leaf area index and canopy height. JULES probably over estimated heterotrophic Rs at Sharpsand Creek when Ts corrected simulated values were compared with measured Rs T,M. The results of this study contribute to a better quantitative understanding of Rs in boreal jack pine fire scars and will facilitate improvements in C cycle modelling. Further work is needed in quantifying autotrophic and heterotrophic contributions to soil respiration in jack pine systems, monitoring soil respiration for extended time periods after fire and improving the ability of JULES to simulate successional vegetation re-growth.
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Bong, Wen Jiann. "Limitations of Zone Models and CFD Models for Natural Smoke Filling in Large Spaces." Thesis, University of Canterbury. Department of Civil and Natural Resources Engineering, 2012. http://hdl.handle.net/10092/10342.
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This research report examines the use of zone modelling compared with CFD modelling to determine when zone model approximation is valid and when a CFD model might be required. A series of computer simulations with enclosures and fires of various sizes was performed to compare the capabilities and limitations of the two computer methods. The relationship between the size of the enclosure space and the size of the fire has been demonstrated in a dimensionless form.
The zone model BRANZFIRE and the CFD model FDS were used for simulating smoke development. The simulations included various full-scale experimental data on both small and large spaces found in the literature. Further simulations of large exemplar spaces with a range of fire sizes were performed to investigate different variables, which have not been examined in full-scale experiments. The simulation results have been compared based on the smoke layer height and the average layer temperature. Zukoski’s smoke filling equation was also used to compare the layer height predictions against BRANZFIRE and FDS.
It was found that different data reduction techniques gave different approximations to the layer height. A perfect match between the experimental data and the model output was very difficult to achieve. FDS showed a large uncertainty of the smoke layer height and temperature in the early stages of fire across the enclosure space. In the later stages, this uncertainly became minimised where the smoke layer height and temperature were fairly uniformly developed across the space.
For fire enclosures with instantaneous steady-state fires, the predictions between BRANZFIRE and FDS agreed well with each other if the fire size and the enclosure size were within a reasonable range. From the modelling of the full-scale experiments, FDS showed favourable layer-height comparisons against the full-scale experimental tests. However, the output results from BRANZFIRE are less comparable with those of FDS for the experiments with fire growth. An appropriate smoke transport time lag should be included for Zukoski’s smoke filling equation and BRANZFIRE; otherwise, they gave conservative estimates of the layer height to smaller fires with a growth phase.
In general, the data reduction methods and zone models should not be used if the fire is too small relative to the enclosure size. A very low temperature rise within the enclosure space would give invalid predictions of the layer height and average layer temperature. This is because there is no clear indication of a separation between the upper and lower smoke layers or temperatures. Single point data of smoke concentrations and temperatures from CFD models should be considered through the entire space or at the specified location of interest. This also applies to an extremely large fire relative to the enclosure size where temperature distribution across the space might not be very homogenous. CFD models could also be used to investigate the details of the smoke properties in the early stages of growing fires, in which the smoke transport lag and the plume effects cannot be seen in BRANZFIRE.
This research is intended to provide guidance for fire engineers by determining which of the computer methods can be used confidently and appropriately as a design tool.
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Fraga, Guilherme Crivelli. "Análise da influência das propriedades radiativas de um meio participante na interação turbulência-radiação em um escoamento interno não reativo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/142495.
Full textAbstract:
A interação turbulência-radiação (TRI, do inglês Turbulence-Radiation Interaction) resulta do acoplamento altamente não linear entre flutuações da intensidade de radiação e flutuações da temperatura e da composição química do meio, e tem-se demonstrado experimentalmente, teoricamente e numericamente que este é um fenômeno relevante em diversas aplicações envolvendo altas temperaturas, especialmente em problemas reativos. Neste trabalho, o TRI é analisado em um escoamento interno não reativo de um gás participante que se desenvolve em um duto de seção transversal quadrada, para diferentes intensidades de turbulência do escoamento e considerando duas espécies distintas para a composição do fluido de trabalho (dióxido de carbono e vapor de água). O objetivo central é avaliar como a inclusão ou não da variação espectral das propriedades radiativas do meio no cálculo influencia a magnitude do TRI. Isso é feito através de simulações numéricas no código de dinâmica dos fluidos computacional Fire Dynamics Simulator (FDS), que resolve, através do método dos volumes finitos, as equações fundamentais que regem o problema – isto é, os balanços de massa, de quantidade de movimento e de energia e a equação de estado – em uma formulação adequada para baixos números de Mach, utilizando um algoritmo de solução explícito e de segunda ordem no tempo e no espaço. A turbulência é modelada através da simulação de grandes escalas (LES, do inglês Large Eddy Simulation), empregando-se o modelo de Smagorinsky dinâmico para o fechamento dos termos submalha; para a radiação térmica, o método dos volumes finitos é utilizado na discretização da equação da transferência radiativa e os modelos do gás cinza e da soma-ponderada-de-gases-cinza (WSGG, do inglês Weighted-Sum-of-Gray-Gases) são implementados como forma de desconsiderar e de incluir a dependência espectral das propriedades radiativas, respectivamente. A magnitude do TRI sobre o problema é avaliada através de diferenças entre as médias temporais dos fluxos de calor superficiais e do termo fonte radiativo obtidas em cálculos que consideram os efeitos do fenômeno e cálculos que os negligenciam. Em geral, a interação turbulência-radiação mostrou ser pouco importante em todos os casos considerados, o que concorda com resultados de outros estudos sobre o tema em escoamento não reativos. Com o modelo WSGG, as contribuições do fenômeno foram maiores do que com a hipótese do gás cinza, evidenciando que a inclusão da variação espectral na solução do problema radiativo tem um impacto sobre a magnitude dos efeitos do TRI. Além disso, é feita uma discussão, em parte inédita no contexto do TRI, sobre diferentes metodologias para a análise do fenômeno. Finalmente, é proposto um fator de correção para o termo fonte radiativo médio no modelo WSGG, que é validado através de sua implementação nos casos simulados. Em estudos futuros, uma análise de sensibilidade sobre os termos constituintes desse fator de correção pode levar a um melhor entendimento de como as flutuações de temperatura se correlacionam com o fenômeno da interação turbulência-radiação.Turbulence-radiation interaction (TRI) results from the highly non-linear coupling between fluctuations of radiation intensity and fluctuations of temperature and chemical composition of the medium, and its relevance in a number of high-temperature problems, especially when chemical reactions are included, has been demonstrated experimentally, theoretically, and numerically. In the present study, the TRI is analyzed in a channel flow of a non-reactive participating gas for different turbulence intensities of the flow at the inlet and considering two distinct species for the medium composition (carbon dioxide and water vapor). The central objective is to evaluate how the inclusion or not of the spectral variation of the radiative properties of a participating gas in the radiative transfer calculations affects the turbulence-radiation interaction. With this purpose, numerical simulations are performed using the computational fluid dynamics Fortranbased code Fire Dynamics Simulator, that employs the finite volume method to solve a form of the fundamental equations – i.e., the mass, momentum and energy balances and the state equation – appropriate for low Mach number flows, through an explicit second-order (both in time and in space) core algorithm. Turbulence is modeled by the large eddy simulation approach (LES), using the dynamic Smagorinsky model to close the subgrid-scale terms; for the thermal radiation part of the problem, the finite volume method is used for the discretization of the radiative transfer equation and the gray gas and weighted-sum-of-gray-gases (WSGG) models are implemented as a way to omit and consider the spectral dependence of the radiative properties, respectively. The TRI magnitude in the problem is evaluated by differences between values for the time-averaged heat fluxes at the wall (convective and radiative) and for the time-averaged radiative heat source calculated accounting for and neglecting the turbulence-radiation interaction effects. In general, TRI had little importance over all the considered cases, a conclusion that agrees with results of previous studies. When using the WSGG model, the contributions of the phenomenon were greater that with the gray gas hypothesis, demonstrating that the inclusion of the spectral variance in the solution of the radiative problem has an impact in the TRI effects. Furthermore, this paper presents a discussion, partly unprecedented in the context of the turbulence-radiation interaction, about the different methodologies that can be used for the TRI analysis. Finally, a correction factor is proposed for the time-averaged radiative heat source in the WSGG model, which is then validated by its implementation in the simulated cases. In future studies, a sensibility analysis on the terms that compose this factor can lead to a better understanding of how fluctuations of temperature correlate with the turbulence-radiation interaction phenomenon.
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Stalcup, Erik James. "Numerical Modeling of Upward Flame Spread and Burning of Wavy Thin Solids." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1417797653.
Full text
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Russo, Filippo. "Avanzamenti nella modellazione dello sviluppo e della dispersione dei fumi nel caso di incendi." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textAbstract:
Gli incendi emettono sostanze tossiche che si disperdono in atmosfera mediante un pennacchio di fumi e che possono rappresentare un rischio per la salute delle persone in zone anche lontane dall’incendio. Per ridurre il rischio di danni alla salute della popolazione, nell’intorno degli impianti a rischio di incidente rilevante e degli impianti di trattamento, smaltimento e stoccaggio di rifiuti le norme di legge prevedono che sia redatto un “piano di emergenza esterna”. Per redigere tale documento è necessaria un’analisi delle conseguenze che un incendio potrebbe causare, modellando lo sviluppo e la dispersione del pennacchio dei fumi e determinando le zone di pericolo per le persone. Le norme di legge, tuttavia, non contengono nessuna indicazione sulla procedura da seguire. Il presente lavoro di tesi, sviluppato durante un tirocinio svolto presso lo Studio “IDF - Ingegneria del Fuoco” di Funo di Argelato (BO), ha avuto lo scopo di contribuire alla messa a punto di una procedura per la modellazione dello sviluppo e della dispersione dei fumi nel caso di incendi all’aperto di combustibili solidi o liquidi. Dopo il Capitolo 1 di introduzione, nel Capitolo 2 è presente la descrizione dei modelli teorici ed empirici che stimano le proprietà del pennacchio dei fumi prodotti dagli incendi di liquido. Il Capitolo 3 è dedicato alla presentazione delle equazioni e dei software FDS (Fire Dynamics Simulator) ed ALOFT-FT necessari per lo studio dello sviluppo e della dispersione dei fumi degli incendi all’aperto; per il calcolo della potenza termica rilasciata sono riportati i modelli basati sulla burning rate e sull’andamento temporale della potenza termica. Il Capitolo 4 descrive l’analisi di un incendio di una pozza mediante i modelli teorici ed empirici. Il Capitolo 5 descrive l’analisi di un incendio di una pozza di esano. Il capitolo 6 descrive l’analisi di un incendio di una balla di PET. Il Capitolo 7 contiene le considerazioni conclusive in merito al lavoro effettuato.
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Svarnas, Ilias. "The artillery fire direction center simulation." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03sep%5FScarnas.pdf.
Full textAbstract:
Thesis (M.S. in Computer Science and M.S. in Modeling, Virtual Environments and Simulation (MOVES))--Naval Postgraduate School, September 2003.Thesis advisor(s): Rudolph Darken, Joseph Sullivan. Includes bibliographical references (p. 51). Also available online.
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Hoffmann, Nicole Andrea. "Computer simulation of fire-sprinkler interaction." Thesis, University of Greenwich, 1990. http://gala.gre.ac.uk/6369/.
Full textAbstract:
The research work presented herein addresses the problem of the mathematical modelling of fire and fire-sprinkler scenarios. This involved the numerical simulation of two-phase, three-dimensional, buoyant, turbulent, recirculating flows. The simulations were carried out in two successive and distinct stages. The first stage dealt with the modelling of buoyant hot turbulent gas flows generated by a fire within room-sized compartments. These single phase studies were based on the field modelling approach to fire simulation. The second part of the study involved the introduction of the cold water droplets through a single sprinkler head, thus, extending the scenario into the more complex two-phase regime. This led to expanding the single-phase fire model to take account of two concurrently present phases, ie. gas/liquid. The strategy used to model the twophase process was the Eulerian-Eulerian technique or volume-fraction method. In order to take into account the physics involved in this process, interphase friction or drag was considered. Furthermore, due to the large difference in temperatures between the hot gases and the cold water droplets it was necessary to introduce interphase heat transfer. Due to the subsequent evaporation of the water droplets interphase mass transfer was also accounted for. Models for both steady-state and time-dependent situations were developed, whereby experimental results of transient fire-sprinkler tests were used for validation. The simulations performed indicated the creation of extremely complex flow fields within the compartments both prior and during sprinkler activation. Phenomena such as the significant cooling of the hot combustion gases caused by the active sprinkler and the evaporation of water droplets have also been predicted. This has been verified by the experimental data. Thus, it can be concluded that the models outlined herein are capable of simulating the complex two-phase fire-sprinkler scenarios. The need for subsequent investigative studies into such areas as the effect of using different auxiliary relationships eg. heat transfer, sprinkler characteristics and gridspacing has been highlighted. In order to complete the validation process, further experimental data needs to be made available. This two-phase technique has proven to be very computationally intensive with simulations requiring days of CPU time. 'Mis is clearly unacceptable. However, it is suggested that parallel computing technology may provide a means for reducing the CPU time involved to hours. It can be concluded that though the model developed requires further investigation and refinements, it provides a basis for a practical and useful fire engineering tool.
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French, Ian Dept of Computer Science Australian Defence Force Academy UNSW. "Visualisation techniques for the computer simulation of bushfires in two dimensions." Awarded by:University of New South Wales - Australian Defence Force Academy. Dept. of Computer Science, 1992. http://handle.unsw.edu.au/1959.4/38721.
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This thesis examines techniques that provide a method of computer visualisation of bushfire spread. Existing techniques studied include, Kourtz & O???Regan, Green???s Contact, Heat Accumulation, Percolation modelling and Huygens??? Principle by Anderson et.al., French, Roberts, Richards. Many of these techniques are extended as part of a comprehensive study into how they perform in a two dimensional reference frame (ie over flat terrain only). New techniques are defined for Percolation Modelling and Huygens??? Principle. Each technique is examined in a series of test cases which include computer simulations with no wind, constant wind, variable wind, variable vegetation (including patchy fuel and two fuels) and where fuel burns out. These test cases provide: (a) an incremental approach to understanding the operation of each technique; (b) a basis for comparison; and (c) verification of correctness of the technique in two dimensions. Several of the techniques are shown, by these test cases, to be equivalent. For instance, the Kourtz & O???Regan technique using a square template is equivalent to the Contact Technique, Site percolation is similar to the Heat Accumulation technique and Template percolation is similar to the Contact Technique. Overall the Huygens??? Principle techniques provide the most accurate simulations of bushfire spread.
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Gardelle, Bastien. "Development and resistance to fire of intumescent silicone based coating : fire protection of steel in simulated fire." Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10079/document.
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L'objectif de ce travail de thèse est de développer des revêtements intumescents à base de résines de silicone pour la protection de l'acier en cas d’incendie. Les revêtements intumescents ont pour fonction d'assurer l'intégrité des structures en acier exposées au feu, ce métal perdant une grande partie de ses propriétés mécaniques au-dessus de 550°C. Les revêtements intumescents classiquement utilisés sont formulés à partir de résines organiques ce qui conduit à certaines limitations. Dans ce travail, des revêtements intumescents hybrides organiques-inorganiques à base de résines de silicone ont donc été développés. Dans un premier temps, il est montré que les résines silicones de types RTV (room temperature vulcanized) présentent les meilleures propriétés de barrière thermique. Par la suite, du graphite expansible a été incorporé en tant qu’agent gonflant à la résine silicone, pour permettre l'expansion du revêtement à haute température. Grâce à des interactions spécifiques entre le silicone et le graphite expansé, le revêtement obtenu présente d'excellentes propriétés de protection thermique. Ces résultats ont été attribués à ses propriétés de gonflement, à sa faible conductivité thermique à haute température et à la bonne cohésion du char développé. Des charges minérales supplémentaires ont ensuite été incorporées dans la formulation afin d'augmenter les propriétés mécaniques du char. Enfin, les paramètres essentiels régissant les propriétés de barrières thermiques des revêtements siliconés ont été mises en évidence. En jouant sur ces paramètres, il est possible de formuler des revêtements performants pour la protection de l'acier au cours d'un incendieThe purpose of this Ph.D work is to develop intumescent coatings for the protection of steel against fire. The aim of this coating is to ensure the integrity of steel structure exposed to fire since steel loses more than 50% of its load capacity above 550°C. Intumescent coatings expand in case of fire leading to the formation of an insulative barrier limiting the heat transfer from the heat source to the substrate. Most of these coatings are organic based and thus exhibit some limitations. Thus, in this work, hybrid organic-inorganic coatings based on silicone resins were developed. In a first step, it is shown that room temperature vulcanized silicone rubber is the silicone matrix exhibiting the best insulative properties in fire scenarios. Expandable graphite is then used as blowing agent to make the silicone swell when exposed to fire. Due to several interactions between silicone and expandable graphite at high temperature, the coating exhibits excellent fire performance. This performance was attributed to the swelling properties, the low thermal conductivity at high temperature and the good cohesion of the developed char. Additional fillers such as calcium carbonate and organoclay are incorporated in the formulation to increase the mechanical properties of the char. Finally, the critical parameters governing the insulative properties of intumescent silicone coatings have been determined. Moreover, it was pointed out that it is possible to develop silicone coatings exhibiting better fire performance than commercial intumescent paint for the protection of steel against fire in both hydrocarbon and cellulosic fire scenarios
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Hlaváček, Radek. "Budoucnost brněnského výstaviště." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-391824.
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Site is situated northwest of existing borders of BVV. This location is based on urban design from last semester. The design focuses on function and sustainable design. Fire station is type P4 (2 firefighting groups) for firefighters of Jihomoravský kraj with direct connection to BVV. Because of need to fast access to BVV. The firestation has grounds for training of fire sports and training with car wrecks. Health and safety center (CZAB) with main building and outside area. This center is focused on training public in area of dangers of everyday life. The center is simulator of these risks and is based on living through the situations in safe space under profesional guidance. Center can be connected with BVV. Both grounds are connected together with humanitary hall which serves as training space for firefighters and learning space for CZAB and in case of humanitary needs can be used as humanitary hall.
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Melek, Zeki. "Interactive simulation of fire, burn and decomposition." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85805.
Full textAbstract:
This work presents an approach to effectively integrate into one unified modular
fire simulation framework the major processes related to fire, namely: a burning
process, chemical combustion, heat distribution, decomposition and deformation of
burning solids, and rigid body simulation of the residue. Simulators for every stage
are described, and the modular structure enables switching to different simulators if
more accuracy or more interactivity is desired. A "Stable Fluids" based three gas
system is used to model the combustion process, and the heat generated during the
combustion is used to drive the flow of the hot air. Objects, if exposed to enough
heat, ignite and start burning. The decomposition of the burning object is modeled as
a level set method, driven by the pyrolysis process, where the burning object releases
combustible gases. Secondary deformation effects, such as bending burning matches
and crumpling burning paper, are modeled as a proxy based deformation.
Physically based simulation, done at interactive rates, enables the user to ef-
ficiently test different setups, as well as interact and change the conditions during
the simulation. The graphics card is used to generate additional frames for real-time
visualization.
This work further proposes a method for controlling and directing high resolution
simulations. An interactive coarse resolution simulation is provided to the user as a "preview" to control and achieve the desired simulation behavior. A higher resolution "final" simulation that creates all the fine scale behavior is matched to the preview
simulation such that the preview and final simulations behave in a similar manner.
In this dissertation, we highlighted a gap within the CG community for the
simulation of fire. There has not previously been a physically based yet interactive
simulation for fire. This dissertation describes a unified simulation framework for
physically based simulation of fire and burning. Our results show that our implementation
can model fire, objects catching fire, burning objects, decomposition of
burning objects, and additional secondary deformations. The results are plausible
even at interactive frame rates, and controllable.
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Koo, Sung-Han. "Forecasting fire development with sensor-linked simulation." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4187.
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In fire, any information about the actual condition within the building could be essential for quick and safe response of both fire–fighters and occupants. In most cases, however, the emergency responders will rarely be aware of the actual conditions within a building and they will have to make critical decisions based on limited information. Recent buildings are equipped with numbers of sensors which may potentially contain useful information about the fire; however, most buildings do not have capability of exploiting these sensors to provide any useful information beyond the initial stage of warning about the possible existence of a fire. A sensor–linked modelling tool for live prediction of uncontrolled compartment fires, K– CRISP, has therefore been developed. The modelling strategy is an extension of the Monte– Carlo fire model, CRISP, linking simulations to sensor inputs which controls evolution of the parametric space in which new scenarios are generated, thereby representing real–time “learning” about the fire. CRISP itself is based on a zone model representation of the fire, with linked capabilities for egress modelling and failure prediction for structural members, thus providing a major advantage over more detailed approaches in terms of flexibility and practicality, though with the conventional limitations of zone models. Large numbers of scenarios are required, but computational demands are mitigated to some extent by various procedures to limit the parameters which need to be varied. HPC (high performance computing) resources are exploited in “urgent computing” mode. K–CRISP was demonstrated in conjunction with measurements obtained from two sets of full–scale fire experiments. In one case, model execution was performed live. The thesis further investigates the predictive capability of the model by running it in pseudo real–time. The approach adopted for steering is shown to be effective in directing the evolution of the fire parameters, thereby driving the fire predictions towards the measurements. Moreover, the availability of probabilistic information in the output assists in providing potential end users with an indication of the likelihood of various hazard scenarios. The best forecasts are those for the immediate future, or for relatively simple fires, with progressively less confidence at longer lead times and in more complex scenarios. Given the uncertainties in real fire development the benefits of more detailed model representations may be marginal and the system developed thus far is considered to be an appropriate engineering approach to the problem, providing information of potential benefit in emergency response. Thus, the sensor–linked model proved to be capable of forecasting the fire development super–real– time and it was also able to predict critical events such as flashover and structural collapse. Finally, the prediction results are assessed and the limitations of the model were further discussed. This enabled careful assessment of how the model should be applied, what sensors are required, and how reliable the model can be, etc.
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Rexfort, Claudia. "A contribution to fire detection modelling and simulation." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971472572.
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Rose, Paul Stuart. "Simulation of steel/concrete composite structures in fire." Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/2995/.
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A finite element code has been developed at the University of Sheffield to simulate the structural response of steel and composite framed buildings subjected to fire. The steel skeleton is represented using two-noded line elements, the steel-to-steel connections using spring elements and the flooring system by isotropic flat shell elements. Structures are therefore considered as a complete entity, allowing a more realistic prediction of structural behaviour at elevated temperature. A series of numerical simulations of fire tests carried out on the full-scale, eight-storey composite frame at the BRE laboratory at Cardington in 1995 and 1996 have been conducted. These tests have been subject to a number of significant parametric studies including slab thickness and secondary beam connection strength and stiffness. The concrete floor slab element has also been extended to a layered flat shell element allowing the inclusion of material non-linearities, thermal bowing, thermal degradation, anisotropic properties and a more advanced cracking model. Using the new concrete floor slab element the Cardington fire tests have been simulated in detail, to further understanding of the structural reaction in fire. Another series of parametric studies have been conducted considering again the thickness of the floor slab, the effect of the slab temperature gradient, the compressive strength, tensile strength and load ratios. These have all been compared to results from the Cardington fire tests. Current design methods based on isolated element design are considered by comparing the results of analyses in which the concrete floor is either included as a continuous slab in an extensive subframe, or is treated simply as forming the flanges of composite beams in a three-dimensional skeleton. These examples show clearly the effects of membrane and bridging actions of the continuous floor slab. The implications for future design developments are discussed with particular reference to the parametric studies conducted.
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Murray, John William 1972. "Simulation to assess plumbing and fire protection innovations." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/79988.
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Ezekiel, Samson. "Fire resistance simulation for high strength reinforced concrete." Thesis, London South Bank University, 2015. http://researchopen.lsbu.ac.uk/2084/.
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High strength reinforced concrete (HSRC) has been used more frequently in the construction of high rise buildings and other concrete structures in recent decades due to its advantages and excellent performance over normal strength and conventional reinforced concrete. Some of these advantages include: higher strength, better durability and allowance for provision of using less concrete and smaller section sizes. Although HSRC performs better than normal strength reinforced concrete (NSRC) at ambient temperatures, NSRC has been found to perform better than HSRC at elevated temperatures and fire conditions. Provision of adequate fire resistance for reinforced concrete (RC) structures is essential as fire represents an extreme loading and hazardous condition to which a structure might be exposed during its life span. The fire resistance of RC members is evaluated using a prescriptive approach which is irrational and conservative. Current codes of practice and construction in industry are moving towards performance based fire design method with computing software, which is a rationally based method with each structure designed to meets its own need. This method requires comprehensive knowledge and modelling of concrete and reinforcement material behaviour and their response at elevated temperatures. The fire resistance of HSRC members (columns and beams) in this study was evaluated using a three-dimensional Finite Element (FE) model created in ANSYS. The stress – strain behaviour of concrete proposed in this research was used in modelling the behaviour of concrete in ANSYS, while other concrete and steel material properties were accounted for by using models proposed by other researchers. The fire resistance of the HSRC members is evaluated using coupled field analysis (thermal – structural analysis) with performance based failure criteria provided in the code of practice. The accuracy of the FE model was verified by comparing the thermal response, structural response and predicted fire resistance with fire test results obtained. Using the validated FE model, parametric studies were conducted to investigate the influence of various parameters affecting the fire performance of HSRC members exposed to fire. From the parametric studies conducted, simplified calculation models were developed for evaluating the resistance of HSRC members (columns and beams) exposed to fire. These models were validated with results from ANSYS and a fire resistance test. The simple model accounts for major factors such as member size, load ratio and fire scenario, and therefore can be easily incorporated into structural design. The FE model and simple calculation model provide a rational approach for evaluating the fire resistance of HSRC (members) and predict a more accurate fire resistance than the prescriptive approach.
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盧以霖. "Using Fire Dynamics Simulator to Simulate Fire Spread." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/68683930422513865745.
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碩士國立交通大學
機械工程系所
104
In the past, many researchers and performance-based designs used FDS (Fire Dynamics Simulator) to simulate and investigate the smoke movement in the large scale or complex architecture/constructions. In such case, the designed fire is the only source of heat release rate. However, in many fire incidents, the heat release rate usually is greatly enhanced by fire spread over the combustible materials, especially the wall decoration. When a fire occurs incidentally in a compartment, it can grow by means of the heat transfer (conduction, convection and radiation) to pyrolyze the other surrounding combustibles to generate more fuel vapors to feedback into the fire to let it become stronger and capable of further wider spreading. The cycle repeats continuously. Even if the air in the compartment is depleted or lowered to a certain limit, the resultant high temperature still keeps on the pyrolysis action. Once an opening happens to let air flow into the space, it leads to flashover. During the process, wall decoration plays the major role for fire spreading in addition to the furniture and electrical appliances in the space. If the corresponding material is flammable and combustible, then it can contribute to severe fire spread, especially the vertical wall surfaces. The parametric study is given by using 4 different wall decoration materials (PU Foam, White pine, PVC and Douglas fir) to investigate the corresponding flame spreads in a fire compartment. PU Foam is found easy to be ignited and the spreading fire behavior is the worst one. Inside the room, PU Foam walls are almost burnout at the end of simulation and it causes severe damage. In the meantime, sofas made by PU foam are ignited easily and burned fiercely as well.
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黃育祥. "Fire scene reconstruction by using fire dynamics and fire dynamics simulator (FDS)." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/7b7wxc.
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Liao, Chun-Chieh, and 廖俊傑. "Numerical Simulation and Experimental Diagnosis of a Fire Simulator." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/94639756682633690137.
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碩士淡江大學
航空太空工程學系碩士班
95
The occurrence of fire has always caused a great calamity to mankind. How to carry on the rescue in the fire scene, reduce the injury when the fire occurs, resist expansion of the scene of fire and prevent the occurrence of the fire, etc, are the key subjects that people concentrate for a long time. In this thesis, we use Computational Fluid Dynamic (CFD) software: Fire Dynamics Simulator (FDS) program to simulate the discussion, solving the numerical solution in Navier-Stokes equation. FDS can be used for establishing the conditions similar to fire scene and shows the situation of dynamic simulation. In this thesis, we regarded propane gas as single gas, and measure with three different kinds of gas exporting type and fire source places. In the course of burning simulation of three kinds of different scenes, we are going to discuss following parameters, such as gas composition, thickness, temperature and speed in the combustion furnace and verify the simulation and experiment. The result of simulation shows that the place which putting fire source could influence the diffusion situation of temperature in the space. We also found that the vortices created because of the rising of the hot air collide to the barrier and ceiling or exchange of cold and hot air. From the results of experiment and simulation, we found the average temperature difference were about 11℃ or 11.7% which measured in V-gutter flameholder, 9℃or 8.03% in gas burner and 26℃ or 8.9% in storage fire simulator. The result in simulation is consistence with experiment. This thesis verified the control of flameholder of fire simulator and safety of experiment process at first and confirmed that the FDS software could simulate the fire in fire simulator. We can use the FDS software to simulate the fire before experiment to increase the accuracy of experiment and reduce the cost of experiment.
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Huang, Kuo-Chun, and 黃國俊. "Using Fire Dynamics Simulator(FDS) to Simulate and Analyze Fire Spread in the Movie Theater." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7xrs6z.
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碩士國立交通大學
機械工程系所
106
This thesis mainly uses the FDS to analyze the fire field burning phenomenon by changing the parameters of the location of the escape port, the material of the ceiling , and the material of the wall. The fire source size and position of all scenarios are fixed. The total fire load is 1 MW. It is placed on the left corner of the last row. The growth rate of the fire source is described by the Ultra-fast growth curve. Seat material is fixed to PU. It can be directly observed that as long as the material of the ceiling or wall is non-combustible material, there will be no flashover phenomenon. The fire development with flashover phenomenon can be quantified and illustrated. Taking situation one as an example, the flashover time is 239 seconds, the fully development period is 239 to 508 seconds, and the decay period is 508 to 638 seconds. When the escape ports are all below, compared to having an escape port on the top, such situations are quite long fully development period and can be seen to be more dangerous in such situations, and when the walls, ceiling wall and chair material is PU, which the material has fire spread and flashover phenomenon, compared to the INERT material, and the smoke layer drops very quickly, and the drop in visibility is also very noticeable
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Tsai, Yong-Ren, and 蔡詠任. "Aggregation and Analysis of Fire Sensing Information using Fire Dynamics Simulator." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/02989398897750569987.
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碩士國立雲林科技大學
電機工程系
104
The heat and harmful gases often cause rescuers and victim casualties in the fire field. The rescuers can combine robots into the fire field, robots can get information at the same time. The information enable rescuers to understand where to move forward and the scene factors are not allowed to rescue must retreat immediately. The fire field is unable to carry on the actual test. In this thesis we use Fire Dynamics Simulator (FDS) to simulate the fire field. All types of sensors data are simulated by FDS. In this thesis, the simulation analysis is performed by setting different density of temperature sensors in the fire field. We use the simulated data to reconstruct temperature gradient map and compare similarity with temperature slice map of FDS. Setting oxygen, carbon monoxide and carbon dioxide sensor to observe simulated data whether these gases cause people to harm immediately. The reconstructed temperature gradient map has highest similarity degree at sensor density is 1 meter and 1.5 meter. According to this data, the robots can distribute sensors when they get into the fire field. The oxygen, carbon monoxide and carbon dioxide sensors are not the same as temperature which should distribute in all areas. We only need to distribute them on critical location when the rescue team enter the fire field.
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Lin, Kan-Zhun, and 林侃諄. "Using Fire Dynamics Simulator to Simulate the Fire Suppression Effect of Water Mist in a Theater." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/3a3sr5.
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碩士國立交通大學
機械工程系所
107
This thesis applied Fire Dynamic Simulator (FDS) to study the fire suppression effects of sprinklers in the theater, whose ceiling and wall material is set to be PU. The water droplet sizes of the sprinkler were categorized into three types: 1000µm (traditional sprinkler), 500µm and 100µm. The last two are of water mist. The designed fire source, located in the left corner of the last row of the theater, was in an ultra-fast growth curve and it reached the maximum heat release rate of 1MW. The seat material was PU. The parameters to observe the fire suppression effects were the heat release rate, under-ceiling temperatures, and oxygen concentrations. The simulation results showed that no matter what type of water sprinkle system is activated, the heat release rate, fire spread and temperature under the ceiling are much lower than those without water spray, indicating that the acting sprinkle system can effectively mitigate the fire intensity. The traditional water-spray performance was better than that of the two water mist systems. The main reason is that the traditional sprinkle system provides much more spray water, 13.8 times of water mist ones. At the same amount of water, the peak heat release rates are the same. It is found that the resultant oxygen concentrations for the three systems show not much different, indicating that the "Oxygen Displacement" of the water mist does not demonstrate its effect in FDS. Therefore, the fire suppression effect by the Oxygen Displacement, one of the main effects of water mist could be added in FDS in the near future.
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Chien, Han-Liang, and 簡漢良. "Using Fire Investigation Techniques and Fire Dynamic Simulator (FDS) to Reconstruct a Nightclub Fire Scene." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/72647724341992497799.
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碩士吳鳳科技大學
光機電暨材料研究所
101
This study collected the fire cases of domestic and foreign recreational facilities, including nightclubs, to discuss the fire causes and casualties, and further examined the mortality ratio and probable escape time limits in those cases, in order to show the severity of fires in recreational facilities. The fire incident that took place in ALA Nightclub of Taichung, Taiwan, which caused the most severe casualty in Taiwan, was presented as the case study. The official fire investigation report was reviewed, and the origin of fire was determined. The Architecture and Building Research Institute, Ministry of the Interior, tested the full sized soundproof foam, and found that the firing behavior of soundproof foam is ultrafast reaction. This study used the soundproof foam material identical to that in the fire case, and the thermal analysis was conducted to determine the thermal reaction parameters when the soundproof foam was heated and burning. The was results were used as the input parameters for computer simulation. The latest version of Fire Dynamics Simulator (FDS) program software was used to rebuild the fire scene at ALA Nightclub, so as to obtain the changes in the fire hazard factors, such as temperature, smoke layer height, and carbon monoxide concentration. The cause of death and location of nine victims were analyzed. The results were compared with the official autopsy report to discuss the causes of casualty in this case. Finally, according to the computer simulation and other research findings, this study suggested emergency egress time in recreational facilities as a reference for fire prevention in nightclubs.
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LAI, CHUN-CHENG, and 賴俊呈. "Using Fire Dynamics Simulator (FDS)Program To Reconstruct a Fire Scene-Fire Case in Chiayi City." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/2a4jgw.
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碩士吳鳳科技大學
消防研究所
104
According to the most historic building are construct in wood, and because of the character of wood and historic, the wooden building are easy to be lighten up and rapidly spread flame, and make causalty and property. To determine the fire causes and the basic of the investigation, the situation after frie,witness or the state of person who had been the scene,and the record of the survelliance video recorder of the fire scene are fire investigator depend on.Sometimes,it could be difficult to judge the fire routes or need the data that come from simulator because of the long time burning or the high fire loads that cause the serveously situation after fire.When it can’t be recognized by the situation after fire, it could be determine the fire causes and fire place by fire dynamics simulator. The wooden-building in the Chiayi City is used to be the study, and use the Fire Dynamics Simulator develop by National Institute of Standard and Technology(NIST) and Building and Fire Research Laboratory that belong NIST to run a fire simulation.And to invesigate the fire spread that between the two building is reasonable and if it the same with the station of the witness that record in the frie causes investigation and appraisal report.
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LIN, WAN-LING, and 林宛伶. "Smoke Generation in Experimental and Fire Dynamics Simulator Investigation of Visibility in Fires." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/77yhd6.
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碩士國立雲林科技大學
機械工程系
105
The main reason in the fire of death is smoke. A lot of smoke will make the "visibility" attenuate. People can’t directly observe the surrounding environment that can’t make the correct decision in the fire. Experiment with different kinds of heat release rate (30kW, 100kW) in the 8.8m × 7m × 3.4m space. Discussion of the Fire Dynamics Simulator (FDS) predicts visibility whether it’s proved with hot smoke tests. The results show that the experimental and simulated are very different, FDS predictive visibility is not ideal.
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Liu, Sing-Song, and 劉欣松. "A preliminary study on fire-damage of building by FDS(Fire Dynamics Simulator)." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/09998277770127806442.
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碩士國立中興大學
土木工程學系所
100
During to rapid economic development, human development is increasingly serious, Taiwan is facing a shortage of resources and environmental pullation problems, because recyclability of steel and less environmental pollution, comply with the requirements of sustainable development of nature, steel gradually replaced by concrete buildings. But poor fire resistance is a fatal drawback for steel, the main purpose of this paper is to explore the development of the internal temperature in the fire, high temperature on the deterioration of the steel components. Additional cooling equipment - Fan, explore the effectiveness of reducing indoor and surface temperature. Finally, compare with results by ANSYS analysis, explore the reason for the difference, the advantages and disadvantages in the operation between FDS and ANSYS. Based on the results, prove that the vertical channeling of the heat from the fire source, then by the horizontal diffusion.,satisfy the effects of indoor thermal convection. Cooling equipment - Fan reduces the indoor temperature and extend the time to evacuate, FDS (Fire Dynamics Simulator) compared with ANSYS, better to get the temperature distribution of the real scene of a fire. ANSYS analyze the internal temperature of components, so both in the analysis have a good complementarity.
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CHUN, LEE CHING, and 李靜君. "Fire Dynamics Simulator on Fire Safety of the Hydroelectric Power Plant in Taiwan." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/51251424599458909968.
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碩士吳鳳技術學院
光機電暨材料研究所
97
Power is a fundamental component of industrial development. Due to the rapid industrial development in Taiwan, the demand for power has grown dramatically. Hydroelectric power plants are commonly constructed in underground locations. This can greatly increase the potential fire risks and serve as a detriment to fire escape. From the 70 fire cases documented among power plants in Taiwan in the past 16 years, important information was gained of the causes of fires. With the of site inspection and interview, the power plant in Maan, Gu-guan, Xin-tian-lun #5, Jwolan we obtained the fire safety criteria. of Hydroelectric Power Plant. Following a fire site reconstruction and verification applied the FDS simulation program, a fire protection strategy is proposed with the goal of reducing fire frequency in hydroelectric power plants and as a result, decreases fire casualties and loss. Furthermore, this research is based on literature survey, investigation, engineering analysis, conferences with experts. Consequently, this research results will offer the competent authority of fire control to refer, and to be the follow-up relevant research and regulation.