Journal of Fire Sciences最新文献

{"title":"Nitrogen as an environmentally friendly suppression agent for aircraft cargo fire safety","authors":"M. Diakostefanis, S. Sampath, A. Dinesh, Rainer Beuermann, A. Malkogianni","doi":"10.1177/07349041211034456","DOIUrl":"https://doi.org/10.1177/07349041211034456","url":null,"abstract":"Fire suppression systems in cargo compartments are a certification requirement for commercial aircraft safety. Halon production was banned and usage ends in 2040 according to Montreal Protocol for environmental reasons. This necessitates an alternative environmentally friendly agent. Quantitative analysis of nitrogen as agent established suitability of the suppression system. The Minimum Performance Standards specifies the qualification procedure of an agent through four scenarios – bulk load; containerised load; surface burning; and aerosol can explosion. Empirical sources from Airbus, independent computational fluid dynamics studies and small-scale cup-burner tests indicate suitability of nitrogen specific to aircraft cargo fire suppression. The nitrogen delivery system and the experimental apparatus are presented. Extensive commissioning tests verified instrumentation reliability. All the four scenarios were conducted at Cranfield University, in a replica of a wide-body aircraft cargo compartment. In a reduced oxygen environment (11%) obtained with nitrogen discharge, the aerosol can explosion tests were performed without any evidence of explosion or pressure increase beyond the expected baseline value. The surface burning scenario was completed successfully and passed the Minimum Performance Standard criteria. The maximum average temperature was found to be 220°C (limit – 293°C). All the scenarios passed the Minimum Performance Standard criteria for indicating successful prevention of Class B fire re-ignition. Similarly, the containerised and bulk-load scenarios obtained results that passed the Minimum Performance Standard criteria for successfully maintaining continued fire suppression for a specified period of time. The maximum average temperature in containerised-load fire scenario was found to be 210°C (limit – 343°C) and in bulk-load scenario was 255°C (limit – 377°C). Additional qualification criteria and system design are presented in this article according to the Minimum Performance Standard format. This work can be extended to introduce standard testing for safety critical systems, such as engine bay and lithium-ion fires.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44163003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review on fire suppression by fire sprinklers","authors":"Shehu A Abdulrahman, K. Chetehouna, A. Cablé, Ø. Skreiberg, M. Kadoche","doi":"10.1177/07349041211013698","DOIUrl":"https://doi.org/10.1177/07349041211013698","url":null,"abstract":"Water spray remains the most effective, environment-friendly and economical way of fighting accidental or unwanted fires, and this is largely due to its thermal characteristics. The mechanism of fire suppression by sprinkler water sprays is influenced by numerous factors, which have been the focus of years’-long and on-going research studies to improve its extinguishing performances. A comprehensive review study was carried out in this study to assess the level of technological know-how and current state of research in the field. A total of 2473 published articles spanning 50 years (i.e. 1970–2020) were systematically collected and analysed, whereby more than 100 relevant articles were selected and integrated in the discussion. In particular, the review focuses on research relating to the interactions of sprinkler sprays with flame, fire plume and hot surfaces, aiming to provide a better understanding of the phenomena involved in fire suppression.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/07349041211013698","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65155908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on the flame extension and risk analysis of a diffusion impinging flame in confined compartment","authors":"Aijuan Wang, B. Manescau, K. Chetehouna, S. Rudz, L. Lamoot","doi":"10.1177/07349041211015766","DOIUrl":"https://doi.org/10.1177/07349041211015766","url":null,"abstract":"In this work, an experimental investigation on a diffusion impinging flame in a confined compartment was performed. The objective was to study the influence of confinement on the behavior of a flame impinging the ceiling and to deduce the auto-ignition risk of the smoke produced in the confined compartment. For this, configurations with five confinement levels were constructed by the condition of windows and/or door in the compartment and the variation of the heat release rates was made between 0.5 and 18.6 kW. To evaluate the flame morphology and flame extension length, an image processing method based on the direct linear transformation algorithm and the fire segmentation algorithm was adopted. From the experimental data, it was shown that the heat release rate of 4.6 kW presents a critical value for the flame extension in confined configurations, which corresponds to the equivalence ratio of the enclosure greater than 1, highlighting an under-ventilated environment. In addition, an auto-ignition risk analysis of smoke with unburnt gas in the compartment was carried out. The concentration and temperature of these gases were compared to the lower flammability limits and the auto-ignition temperature. It was observed that there was auto-ignition risk of the smoke under the ceiling, especially in the confined compartment of equivalence ratio greater than 1. Under these conditions, it is possible to have a fire spread to another compartment.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/07349041211015766","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46228816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Household cooking oil use and its bearing on fire safety","authors":"M. Spearpoint, C. Hopkin","doi":"10.1177/07349041211012994","DOIUrl":"https://doi.org/10.1177/07349041211012994","url":null,"abstract":"Cooking oil fires present a reasonable worst-case hazard when considering thermal radiation to occupants close to a kitchen hob/cooktop. Shallow or deep frying, the activity frequency and the oil volume may contribute to the risk. A review of cooking oil use is presented via consumer purchasing habits, studies on the health effects of cooking with oil and statistics related to the disposal of cooking oil waste. An online survey provides further data on current cooking practices. Olive oil, vegetable oil or pure sunflower appear to be the most common types. Results suggest that cooking on a hob occurs 4 times per month for deep frying and 17 times per month for shallow frying. A design value of 250 mL is advocated for all frying activities with a frequency of 11 times per month. Design volumes of 2.5 L and 150 mL are proposed for deep and shallow frying, respectively.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/07349041211012994","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46726085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical assessment for aircraft cargo compartment fire suppression system safety","authors":"Yifang Xiong, M. Diakostefanis, A. Dinesh, S. Sampath, T. Nikolaidis","doi":"10.1177/07349041211003208","DOIUrl":"https://doi.org/10.1177/07349041211003208","url":null,"abstract":"Fire on board an aircraft cargo compartment can lead to catastrophic consequences. Therefore, fire safety is one of the most important considerations during aircraft design and certification. Conventionally, Halon-based agents were used for fire suppression in such cases. However, an international agreement under the Montreal Protocol of 1994 banned further production of Halon and several other halocarbons considered harmful to the environment. There is therefore a requirement for new suppression agents, along with suitable system design and certification. This article aims to describe the creation of a mechanism to validate a preliminary design for fire suppression systems using Computational Fluid Dynamics and provide further guidance for fire suppression experiments in aircraft cargo compartments. Investigations were performed for the surface burning fire, one of the fire testing scenarios specified in the Minimum Performance Standard, using the numerical code Fire Dynamics Simulator. This study investigated the use and performance of nitrogen, a potential replacement for Halon 1301, as an environmentally friendly agent for cargo fire suppression. Benchmark fires using the pyrolysis model and fire design model were built for the surface-burning fire scenario. Compared with experiment results, the two Computational Fluid Dynamics models captured the suppression process with high accuracy and displayed similar temperature and gas concentration profiles. Fire consequences in response to system uncertainties were studied using fire curves with various fire growth rates. The results suggested that using nitrogen as a fire suppression agent could achieve a lower post-suppression temperature compared to a Halon 1301-based system. It can therefore be considered as a potential candidate for aircraft cargo fire suppression. Such work will feed directly into system safety assessments during the early design stages, where analyses must precede testing. Future work proposed for the application of this model can be extended to other fire scenarios such as buildings, shipping, and surface transport vehicles.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/07349041211003208","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49316308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Towards real-time fire data synthesis using numerical simulations","authors":"W. Jahn, Frane Sazunic, C. Sing-Long","doi":"10.1177/0734904121993449","DOIUrl":"https://doi.org/10.1177/0734904121993449","url":null,"abstract":"Synthesising data from fire scenarios using fire simulations requires iterative running of these simulations. For real-time synthesising, faster-than-real-time simulations are thus necessary. In this article, different model types are assessed according to their complexity to determine the trade-off between the accuracy of the output and the required computing time. A threshold grid size for real-time computational fluid dynamic simulations is identified, and the implications of simplifying existing field fire models by turning off sub-models are assessed. In addition, a temperature correction for two zone models based on the conservation of energy of the hot layer is introduced, to account for spatial variations of temperature in the near field of the fire. The main conclusions are that real-time fire simulations with spatial resolution are possible and that it is not necessary to solve all fine-scale physics to reproduce temperature measurements accurately. There remains, however, a gap in performance between computational fluid dynamic models and zone models that must be explored to achieve faster-than-real-time fire simulations.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/0734904121993449","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45064733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brominated flame-retardant composition in firefighter bunker gear and its thermal performance analysis","authors":"Vincent N Mokoana, J. Asante, J. Okonkwo","doi":"10.1177/07349041211001296","DOIUrl":"https://doi.org/10.1177/07349041211001296","url":null,"abstract":"Firefighting bunker gear is manufactured from flame-retardant materials, which resist ignition and delay flame spread. However, concerns have been emerging on the potential harmful effects of some flame retardants (FRs) commonly used in flame-retarding materials, particularly the brominated flame retardants. This study investigated the presence of flame retardants in bunker gear, particularly polybrominated diphenyl ethers and their congeners in the garments, and evaluated their impact on thermal performance. X-ray fluorescence spectroscopy was used to ascertain the presence of bromine as a possible indicator for brominated flame retardants. X-ray fluorescence results indicated the presence of Br in all samples, ranging from 444 to 20,367 µg/g. Further analysis via gas chromatography–mass spectrometry was done on samples. Brominated flame retardants, particularly polybrominated diphenyl ethers and hexabromocyclododecane, were detected in all samples with concentrations ranging from 261.61 to 1001.77 µg/g and 0.01 to 0.07 µg/g, respectively. The cone calorimeter was used, with 50 and 75 kW/m2 heat fluxes, to investigate the impact of the brominated flame-retardant concentrations, if any, on thermal performance. New bunker garments, particularly those with lower Br and brominated flame-retardant concentrations, were observed to have higher thermal performance.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/07349041211001296","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49014500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a pyrolysis model for oriented strand board. Part I: Kinetics and thermodynamics of the thermal decomposition","authors":"Junhui Gong, Hong Zhu, Hongen Zhou, S. Stoliarov","doi":"10.1177/0734904120982887","DOIUrl":"https://doi.org/10.1177/0734904120982887","url":null,"abstract":"Oriented strand board is a widely used construction material responsible for a substantial portion of the fire load of many buildings. To accurately model the response of oriented strand board to fire, thermogravimetric analysis, differential scanning calorimetry, and microscale combustion calorimetry tests were carried out to construct a thermal decomposition model using a numerical solver, ThermaKin, and a hill climbing optimization algorithm. The model included a single-step water vaporization reaction and four consecutive reactions representing thermal decomposition of organic constituents of oriented strand board. The experiments and modeling revealed that the first two of the four reactions are endothermic, while the last two are exothermic. The net heat of decomposition was found to be near zero. The heat capacities of condensed-phase species and heats of combustion of evolved gases were also determined. The heats of combustion were found to vary over the course of decomposition—the trend captured by the model. Development of a complete pyrolysis model for this material will be a subject of Part II of this work.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/0734904120982887","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48945729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An analysis of the WTC fires using CIB correlations and simple modeling","authors":"J. Quintiere","doi":"10.1177/0734904121989670","DOIUrl":"https://doi.org/10.1177/0734904121989670","url":null,"abstract":"CIB correlations for compartment burning rates and average gas temperatures are examined for accuracy, utility, and generality. The results are applied to modeling the fire on 9/11 in WTC 1. Specific information is used from the NIST investigation. It is demonstrated that simple heat transfer modeling can predict the truss steel rod temperatures for the E119 tests of WTC done by NIST. The CIB temperature correlation and steel truss modeling are used to predict burning conditions for the WTC 1 96th floor fire and compared to the NIST results. Here a consideration of fuel loads from 20 to 40 kg/m2 was considered compared to just 20 used by NIST. The results suggest that the fully insulated truss bar temperatures would achieve higher values for higher fuel loads. A critical steel truss temperature of 650°C could support failure of the trusses as a theory for the collapse of the towers.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/0734904121989670","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45390317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The character of residential cooktop fires","authors":"Yue Hu, Jian Chen, M. Bundy, A. Hamins","doi":"10.1177/0734904121990392","DOIUrl":"https://doi.org/10.1177/0734904121990392","url":null,"abstract":"A series of experiments was conducted to investigate the global preignition and combustion characteristics of corn oil heated in 9.7 to 26 cm diameter pans by a residential electric-coil element cooktop. For comparison, torch-ignited gasoline, heptane, and corn oil experiments were conducted in the same configuration except without the heating element energized. Heating oil on a typical electric cooktop leads to vaporization and generation of an aerosol cloud followed by autoignition. The evolution of the light-extinction coefficient before autoignition is measured and shown to be related to the pan diameter and initial fuel mass. Continued heating leads to enhanced vaporization of the burning oil and growing fires with the peak heat release rate, radiative heat flux, radiative fraction, and peak flame height larger than the gasoline fires regardless of pan diameter. CO and soot yields, and the CO/CO2 ratio are measured to decrease with pan diameter.","PeriodicalId":15772,"journal":{"name":"Journal of Fire Sciences","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2021-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/0734904121990392","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46945642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}