{"title":"Experimental study on the ceiling jet characteristics caused by carriage fire in an inclined tunnel: Temperature distribution and flame extension","authors":"Tong Xu, Fei Tang, Jianping Zhang","doi":"10.1016/j.proci.2024.105274","DOIUrl":null,"url":null,"abstract":"This work was aimed at investigating the temperature profile and flame extension characteristics of the ceiling jet, which was induced by the fire ejected from a carriage in an inclined tunnel. A series of experiments were conducted in a 1 : 6 reduced-scale model, including a compartment with a window in an inclined tunnel (from 0 to 10 %). Tests were conducted with various heat release rates (HRRs) and opening dimensions. Results showed that with the decreasing ventilation factor, the mixing degree of the air and fuel gases is weakened inside the compartment and the average temperature at the continuous flames ejecting stage is also reduced. For a given opening size, the tunnel slope is shown to affect the temperature distribution inside the enclosure only before reaching the steady burning stage, after which the temperature inside the compartment becomes almost uniform independent of the tunnel slope. In the transverse direction, both the temperature profile and flame extension length under the tunnel ceiling are found to be insensitive to the tunnel slope, whereas in the longitudinal direction, the flame extension length is increased in the upward direction while decreased in the downward direction due to thermal buoyancy. Based on dimensionless analysis, a new correlation was developed incorporating the effects of HRRs, opening sizes and tunnel slopes for the longitudinal flame extension in upward and downward directions, which is found to be in good agreement with the present data and also available data in the literature. The experimental data and the correlation developed are important in understanding the extension behavior of the ejected fire from a carriage in an inclined tunnel, which are essential to assess the thermal hazard and risk of fire spreading to adjacent vehicles.","PeriodicalId":408,"journal":{"name":"Proceedings of the Combustion Institute","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Combustion Institute","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.proci.2024.105274","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
This work was aimed at investigating the temperature profile and flame extension characteristics of the ceiling jet, which was induced by the fire ejected from a carriage in an inclined tunnel. A series of experiments were conducted in a 1 : 6 reduced-scale model, including a compartment with a window in an inclined tunnel (from 0 to 10 %). Tests were conducted with various heat release rates (HRRs) and opening dimensions. Results showed that with the decreasing ventilation factor, the mixing degree of the air and fuel gases is weakened inside the compartment and the average temperature at the continuous flames ejecting stage is also reduced. For a given opening size, the tunnel slope is shown to affect the temperature distribution inside the enclosure only before reaching the steady burning stage, after which the temperature inside the compartment becomes almost uniform independent of the tunnel slope. In the transverse direction, both the temperature profile and flame extension length under the tunnel ceiling are found to be insensitive to the tunnel slope, whereas in the longitudinal direction, the flame extension length is increased in the upward direction while decreased in the downward direction due to thermal buoyancy. Based on dimensionless analysis, a new correlation was developed incorporating the effects of HRRs, opening sizes and tunnel slopes for the longitudinal flame extension in upward and downward directions, which is found to be in good agreement with the present data and also available data in the literature. The experimental data and the correlation developed are important in understanding the extension behavior of the ejected fire from a carriage in an inclined tunnel, which are essential to assess the thermal hazard and risk of fire spreading to adjacent vehicles.
期刊介绍:
The Proceedings of the Combustion Institute contains forefront contributions in fundamentals and applications of combustion science. For more than 50 years, the Combustion Institute has served as the peak international society for dissemination of scientific and technical research in the combustion field. In addition to author submissions, the Proceedings of the Combustion Institute includes the Institute''s prestigious invited strategic and topical reviews that represent indispensable resources for emergent research in the field. All papers are subjected to rigorous peer review.
Research papers and invited topical reviews; Reaction Kinetics; Soot, PAH, and other large molecules; Diagnostics; Laminar Flames; Turbulent Flames; Heterogeneous Combustion; Spray and Droplet Combustion; Detonations, Explosions & Supersonic Combustion; Fire Research; Stationary Combustion Systems; IC Engine and Gas Turbine Combustion; New Technology Concepts
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