Modelling extinction/re-ignition processes in fire plumes under oxygen-diluted conditions using flamelet tabulation approaches

IF 1.9 4区 工程技术 Q4 ENERGY & FUELS
Li Ma, F. Nmira, J. Consalvi
{"title":"Modelling extinction/re-ignition processes in fire plumes under oxygen-diluted conditions using flamelet tabulation approaches","authors":"Li Ma, F. Nmira, J. Consalvi","doi":"10.1080/13647830.2022.2036373","DOIUrl":null,"url":null,"abstract":"The main objective of this article is to investigate the capability of the flamelet progress variable (FPV) model to capture the extinction processes observed in under-ventilated fire scenarios. To this end, large eddy simulation (LES) of the methane line fire plumes in oxygen-reduced environments down to global extinction, investigated experimentally at the University of Maryland (UMD), is performed. Two experimental burner configurations, that differ by the presence (anchored) or not (non-anchored) of an oxygen anchor to stabilise the flame base, are considered leading to two different extinction modes. Both the FPV and the steady laminar flamelet (SLF) model coupled with a presumed filtered density function (FDF) are considered. The Rank Correlated Full Spectrum k-distribution (RCFSK) model is used as a gas radiative property model. In both non-anchored and anchored scenarios, the FPV model reproduces with fidelity the evolution of the fire plume structure, radiative loss, and combustion efficiency with decreasing down to global extinction, without introducing any adjustable constant. The extinction in the non-anchored scenario occurs owing to flame-based detachment coupled to the generation of a buoyancy-driven vortex and is found to be very sensitive to the grid resolution in the near burner region. The present results suggest that these processes can be adequately resolved with a spatial resolution of 2.5 mm in this region. The SLF model, for its part, provides reliable predictions comparable to the FPV as long as no local extinction/re-ignition process occurs.","PeriodicalId":50665,"journal":{"name":"Combustion Theory and Modelling","volume":"26 1","pages":"613 - 636"},"PeriodicalIF":1.9000,"publicationDate":"2022-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Combustion Theory and Modelling","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1080/13647830.2022.2036373","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 2

Abstract

The main objective of this article is to investigate the capability of the flamelet progress variable (FPV) model to capture the extinction processes observed in under-ventilated fire scenarios. To this end, large eddy simulation (LES) of the methane line fire plumes in oxygen-reduced environments down to global extinction, investigated experimentally at the University of Maryland (UMD), is performed. Two experimental burner configurations, that differ by the presence (anchored) or not (non-anchored) of an oxygen anchor to stabilise the flame base, are considered leading to two different extinction modes. Both the FPV and the steady laminar flamelet (SLF) model coupled with a presumed filtered density function (FDF) are considered. The Rank Correlated Full Spectrum k-distribution (RCFSK) model is used as a gas radiative property model. In both non-anchored and anchored scenarios, the FPV model reproduces with fidelity the evolution of the fire plume structure, radiative loss, and combustion efficiency with decreasing down to global extinction, without introducing any adjustable constant. The extinction in the non-anchored scenario occurs owing to flame-based detachment coupled to the generation of a buoyancy-driven vortex and is found to be very sensitive to the grid resolution in the near burner region. The present results suggest that these processes can be adequately resolved with a spatial resolution of 2.5 mm in this region. The SLF model, for its part, provides reliable predictions comparable to the FPV as long as no local extinction/re-ignition process occurs.
用火焰表法模拟氧气稀释条件下火焰羽流的熄灭/再点燃过程
本文的主要目的是研究火焰进程变量(FPV)模型捕捉在通风不足的火灾场景中观察到的熄灭过程的能力。为此,在马里兰大学(UMD)进行了实验研究,对氧气减少环境中甲烷线火羽的大涡模拟(LES)进行了研究。两种实验燃烧器配置的不同之处在于存在(锚定)或不存在(非锚定)氧锚来稳定火焰基础,被认为会导致两种不同的熄灭模式。同时考虑了FPV和稳定层流小火焰(SLF)模型与假定的过滤密度函数(FDF)耦合。采用秩相关全谱k分布(RCFSK)模型作为气体辐射特性模型。在非锚定和锚定两种情况下,FPV模型都能准确地再现火焰羽流结构、辐射损失和燃烧效率的演变过程,并且不需要引入任何可调常数。非锚定情况下的消光是由于火焰分离和浮力驱动涡的产生而发生的,并且对近燃烧器区域的网格分辨率非常敏感。目前的结果表明,这些过程可以在该区域以2.5 mm的空间分辨率充分解决。就SLF模型而言,只要不发生局部熄灭/重燃过程,它就能提供与FPV相当的可靠预测。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Combustion Theory and Modelling
Combustion Theory and Modelling 工程技术-工程:化工
CiteScore
3.00
自引率
7.70%
发文量
38
审稿时长
6 months
期刊介绍: Combustion Theory and Modelling is a leading international journal devoted to the application of mathematical modelling, numerical simulation and experimental techniques to the study of combustion. Articles can cover a wide range of topics, such as: premixed laminar flames, laminar diffusion flames, turbulent combustion, fires, chemical kinetics, pollutant formation, microgravity, materials synthesis, chemical vapour deposition, catalysis, droplet and spray combustion, detonation dynamics, thermal explosions, ignition, energetic materials and propellants, burners and engine combustion. A diverse spectrum of mathematical methods may also be used, including large scale numerical simulation, hybrid computational schemes, front tracking, adaptive mesh refinement, optimized parallel computation, asymptotic methods and singular perturbation techniques, bifurcation theory, optimization methods, dynamical systems theory, cellular automata and discrete methods and probabilistic and statistical methods. Experimental studies that employ intrusive or nonintrusive diagnostics and are published in the Journal should be closely related to theoretical issues, by highlighting fundamental theoretical questions or by providing a sound basis for comparison with theory.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信