Fire Safety Science最新文献

{"title":"Enabling the Investigation of Structure Vulnerabilities to Wind- Driven Firebrand Showers in Wildland-Urban Interface (WUI) Fires","authors":"S. Manzello","doi":"10.3801/iafss.fss.11-83","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-83","url":null,"abstract":"Wind-driven firebrand showers are a major cause of structural ignition in Wildland-Urban Interface (WUI) fires. Past firebrand investigations have not been able to quantify the vulnerabilities of structures to ignition from firebrand showers, as it is difficult to develop a measurement method to replicate wind-driven firebrand attack on structures that occur in actual WUI fires. To address this problem, research has been undertaken in an intricate area involving the quantification of structure vulnerabilities to wind-driven firebrand showers. This type of firebrand research has never been possible prior to the development of the NIST Firebrand Generator, also referred to as the NIST Dragon. Due the complexity of the WUI fire problem, great strides must be made to recruit the next generation of researchers to fire safety science from diverse backgrounds. This paper closes with a discussion of ongoing workshop activities intended to achieve this, as well as some challenges for future WUI fire research.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89346886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of the pyrolysis of plywood exposed to heat fluxes under cone calorimeter","authors":"T. Fateh, F. Richard, T. Rogaume","doi":"10.3801/IAFSS.FSS.11-208","DOIUrl":"https://doi.org/10.3801/IAFSS.FSS.11-208","url":null,"abstract":"In this paper, the thermal decomposition of plywood is investigated based on the solid mass loss rate (MLR) modeling. The multi-scale approach followed here allows first to establish, at a small scale, the kinetic mechanism during the solid thermal decomposition and then validate it at a larger scale. At small scale, experiments were conducted by using Thermo-gravimetric analysis (TGA) coupled to gas analysis with the FTIR technique under nitrogen and air atmospheres for five heating rates. Thermo-gravimetric results were also used to propose a kinetic mechanism for the thermal decomposition of the sample. The kinetic parameters of the different identified reactions were estimated by using an optimization technique, namely the Genetic Algorithms (GA) method. The mass loss rate model predictions show a good agreement with the experimental data. At a larger scale, experiments were carried out in a cone calorimeter coupled to FTIR gas analysis under air atmosphere. The pyrolysis model developed at the TGA scale was used in numerical simulations of cone calorimeter experiments taking into account the heat transfer modeling into the sample. The thermal properties (e.g. thermal conductivity and specific heat capacity) of the condensed phase species (which are products given by the thermal decomposition of the virgin material) identified at the TGA scale were estimated for an incident heat flux of 30 kW.m -2 with the same optimization technique used at the small scale: the GA method. The same work has also been conducted with a simpler well known pyrolysis model developed for charring materials. The results have been compared to those of the first mechanism in order to show the influence of the complexity of the model on the prediction of the thermal decomposition of plywood. The heat transfer model was kept the same for both pyrolysis models. Only the number of identified condensed phase reactions and species is different. The detailed mechanism (5 steps) gives better results than the simpler one (3steps) concerning the mass loss rate prediction and worse results for the temperature prediction of the back surface of the sample. However the 3 steps model gives unrealistic results concerning the prediction of the condensed phase species mass fractions. In fact, the 3 steps model predicts that plywood is not fully burned at the end of the test (for 30 kW.m -2 ) which was not observed in the experiment.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83763190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective stress method to be used in beam finite elements to take local instabilities into account","authors":"J. Franssen, Baptiste Cowez, T. Gernay","doi":"10.3801/IAFSS.FSS.11-544","DOIUrl":"https://doi.org/10.3801/IAFSS.FSS.11-544","url":null,"abstract":"In the fire situation, Bernoulli beam finite elements are the workhorse used in numerical calculation model for simulating the behaviour of the structure. Such finite elements treat all sections as class 1 (stocky) sections whatever the slenderness of the plates that make the section, allowing the development of a full plastic stress distribution in the section which leads to complete plastic redistribution along the members in the structure. This type of element is thus not adapted for modeling structures that contain slender sections of class 2, 3 or 4. This document presents a new approach to take into account local instabilities in slender sections using beam finite elements. The new approach is based on an effective constitutive law of steel. The effective law is not symmetrical with respect to tension and compression because, in tension, the stress-strain relationship is not modified whereas, in compression, the stress-strain relationship is modified.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87599672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of Particle Imaging Velocimetry in Cone Calorimeter experiments","authors":"S. Delcour, D. Herbert, F. Ouf, A. Coppalle, N. Azéma, L. Ferry, Lopez-Cuesta Jose-Marie, F. Salm, M. Talbaut, J. Yon","doi":"10.3801/iafss.fss.11-152","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-152","url":null,"abstract":"Experimental results are reported on the feasibility of particle imaging velocimetry in a cone calorimeter. PolyMethyl MethAcrylAte (PMMA) plates have been contaminated at their surface by alumina particles (Dev=4.4 μm) as seeding particles allowing PIV analysis. Particles are released by bubble bursting during the thermal degradation of the PMMA for each heat flux investigated (25, 35 and 45 kW/m). A “layer” of particles could be noticed for the highest heat flux (35 and 45 kW/m) while for the smallest flux (25 kW/m), the release is confined and more erratic. Velocity increases as a function of the height above the polymer surface from 0.03 m/s at the PMMA surface to 0.3 m/s at the bottom of the conical heater and these results are in good agreement with previous experiments and numerical simulations. As an overall conclusion, this first attempt demonstrates the huge potential of PIV analysis, associated to our deposition set-up, for investigating flow field during cone calorimeter experiments involving bubbling polymers.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73820593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Raised Walkway Design on Evacuation Behaviour in Rail Tunnels","authors":"Frida Vermina Lundström, Jenny Ahlfont, D. Nilsson","doi":"10.3801/iafss.fss.11-1091","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-1091","url":null,"abstract":"The use of raised walkways in rail tunnels has the potential to significantly improve evacuation conditions, however there is limited research that has so far focused on walkway design from an evacuation perspective. An experiment was therefore performed to explore the effect of walkway design, namely walkway width and evacuation aids, on evacuation behaviour, e.g., people’s perception, movement speeds and flow rate. The results indicate that a walkway width of more than approximately one metre (0.9 to 1.05 m) leads to higher movement speeds and increased sense of safety. Handrails and a tactile edge marker are often appreciated evacuation aids as they are perceived as facilitating and safety-enhancing features. Based on the results, a correlation between flow rate and walkway width has been developed. This correlation and the collected data may potentially be used in future cost-benefit analyses to shed light on the most appropriate walkway design for specific tunnels.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75347222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A validation data-set and suggested validation protocol for ship evacuation models","authors":"E. Galea, S. Deere, Robert Brown, L. Filippidis","doi":"10.3801/IAFSS.FSS.11-1115","DOIUrl":"https://doi.org/10.3801/IAFSS.FSS.11-1115","url":null,"abstract":"An evacuation model validation data-set collected as part of the EU FP7 project SAFEGUARD is presented. The data was collected from a cruise ship operated by Royal Caribbean International (CS). The trial was a semi-unannounced assembly trial conducted at sea and involved some 2500 passengers. The trial took place at an unspecified time however, passengers were aware that on their voyage an assembly exercise would take place. The validation data-set consists of passenger; response times, starting locations, end locations and arrival times in the assembly stations. The validation data were collected using a novel data acquisition system consisting of ship-mounted beacons, each emitting unique Infra-Red (IR) signals and IR data logging tags worn by each passenger. The results from blind simulations using maritimeEXODUS for the assembly trial are presented and compared with the measured data. Three objective measures are proposed to assess the goodness of fit between the predicted model data and the measured data.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75037901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-time Stochastic Evacuation Models for Decision Support in Actual Emergencies","authors":"A. Cuesta, D. Alvear, O. Abreu, Delfín Silió","doi":"10.3801/iafss.fss.11-1063","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-1063","url":null,"abstract":"This paper introduces and proposes the use of evacuation models for decision support during actual emergencies. Two examples are presented: EvacTrain 2.0 and EvacTunnel. The proposed models are essentially stochastic, quick and easy to use and can generate and process results of several simulations within a few seconds. The main output parameter is the percentile (0.90, 0.95 or 0.99 th) of total evacuation times. They also provide other statistical characteristics and additional outputs. Both models have been compared with other validated evacuation models. Results suggest that the proposed models provide consistent and reliable results. The general findings described in this paper suggest that it is possible to develop efficient evacuation models for supporting emergency decisions in real-time.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85488006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flame retardant polyurethanes based on novel phosphonamidate additives","authors":"S. Gaan, M. Neisius, Olivia Cuchere, S. Liang, H. Mispreuve, Foam Partner","doi":"10.3801/iafss.fss.11-821","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-821","url":null,"abstract":"Development of new halogen-free flame retardants for application in polymer is becoming important due to ban of some existing halogenated flame retardants, ineffectiveness of existing flame retardant additives and higher fire performance requirements for materials. Polyurethane is an important class of polymer finding application in diverse areas like textile coatings, wood coatings, foams, fibers, cables, adhesives etc. There is a great need to develop halogen free flame retardants for various PU based materials. In this work we have reported synthesis of novel phosphonamidates as flame retardant additives and their application in manufacturing flame retardant flexible PU foams and flame retardant polyester PU coated fabrics. Furthermore the flame retardant properties and thermal decomposition characteristics of the PU based materials have been evaluated. The novel phosphonamidate derivatives have superior fire performance properties as compared to existing commercial flame retardant additives and work primarily in gas phase by recombining H* and OH* radicals.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76400902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating the Time-of-Involvement of Bulk Packed Lithium-Ion Batteries in a Warehouse Storage Fire","authors":"B. Ditch, G. Yee, M. Chaos","doi":"10.3801/iafss.fss.11-1024","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-1024","url":null,"abstract":"A novel experimental approach was developed to evaluate the hazard posed by bulk storage of Li-ion batteries in warehouse scenarios. The flammability characteristics of cartoned small-format Li-ion batteries were evaluated via free-burn fire tests of three-tier-high rack storage arrays. For each test, only the ignition flue area of the array was lined with commodity as a means of reducing the required quantity of Li-ion batteries. Effort was placed on measurement of the fire development and, more importantly, the time of significant battery involvement, a key parameter in the hazard analysis of these fires. This parameter was inferred through diagnostics of the convective gas flow, and corroborated with visual observations and analyses of combustion products. For the tests considered herein, Li-ion batteries are shown to contribute significantly to the severity of the storage fires within 5 minutes of ignition.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83929547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pyrolysis and Oxidation of Cardboard","authors":"G. Agarwal, Gang Liu, B. Lattimer","doi":"10.3801/iafss.fss.11-124","DOIUrl":"https://doi.org/10.3801/iafss.fss.11-124","url":null,"abstract":"Predicting the burning of cardboard requires a detailed understanding of the pyrolysis and char oxidation. An experimental study was performed to quantify the decomposition kinetics, heat of decomposition for pyrolysis, and the heat of combustion of the evolved pyrolysis gases and char oxidation. Parameters were determined using data from a simultaneous TGA / DSC as well as the microscale combustion calorimeter. From TGA data, a double independent reaction kinetic model was sufficient to describe the decomposition of cardboard due to a softened hemicellulose peak. The heat of combustion of pyrolysis gases was a factor of two less than that of the char. However, due to the lower mass loss rate of char, the heat release rate due to the char was less than half of that associated with the evolved pyrolysis gases.","PeriodicalId":12145,"journal":{"name":"Fire Safety Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74474648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}