Experimental study on burning rate and radiative heat transfer of two rectangular fires with different aspect ratios in open space

IF 5.8 2区 工程技术 Q1 ENGINEERING, MECHANICAL
Gexin Wu , Bo Li , Yangjin Shi , Kaihua Lu , Yulun Zhang
{"title":"Experimental study on burning rate and radiative heat transfer of two rectangular fires with different aspect ratios in open space","authors":"Gexin Wu ,&nbsp;Bo Li ,&nbsp;Yangjin Shi ,&nbsp;Kaihua Lu ,&nbsp;Yulun Zhang","doi":"10.1016/j.ijheatmasstransfer.2025.127847","DOIUrl":null,"url":null,"abstract":"<div><div>Combustible liquid fuels can form unequal multi-pool fires upon leakage or container breach, characterized by intense burning and high heat transfer. Understanding the burning rate and radiative heat transfer mechanisms of such fires and developing predictive models are crucial for enhancing thermal management in the chemical industry. This study used two unequal rectangular pool fires (long-side ratios 1:1 to 1:4) with nearest long-edge spacings of 0–100 cm to mimic related asymmetric scenarios. Results showed that the flame tilt angle exhibited a non-monotonic trend, increasing initially and then decreasing as the pool spacing increased. Compared with the larger scale pool, the smaller scale pool had a weaker air entrainment capacity, leading to more pronounced changes in flame tilt angle under the influence of negative pressure between two fire sources. The burning rate of two pools demonstrated a parabolic trend with respect to the dimensionless spacing (<em>S</em>/<em>D</em>), peaking at <em>S</em>/<em>D</em> = 2. By introducing burning rate ratios under different flame merging states, a burning rate increment prediction model was developed. Simultaneously, it was observed that the radiative heat flux presented a rising-then-falling trend along the vertical height. To simplify computational complexity, an optimized multi-point source method was proposed to predict the external radiation. This method modeled the continuous and intermittent flames as a cuboid and a triangular prism, respectively. The total quantity of point sources was determined by discretizing the flame length at intervals of pool width. The point source numbers for continuous and intermittent flames were calculated via volume proportions.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127847"},"PeriodicalIF":5.8000,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Heat and Mass Transfer","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0017931025011822","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
引用次数: 0

Abstract

Combustible liquid fuels can form unequal multi-pool fires upon leakage or container breach, characterized by intense burning and high heat transfer. Understanding the burning rate and radiative heat transfer mechanisms of such fires and developing predictive models are crucial for enhancing thermal management in the chemical industry. This study used two unequal rectangular pool fires (long-side ratios 1:1 to 1:4) with nearest long-edge spacings of 0–100 cm to mimic related asymmetric scenarios. Results showed that the flame tilt angle exhibited a non-monotonic trend, increasing initially and then decreasing as the pool spacing increased. Compared with the larger scale pool, the smaller scale pool had a weaker air entrainment capacity, leading to more pronounced changes in flame tilt angle under the influence of negative pressure between two fire sources. The burning rate of two pools demonstrated a parabolic trend with respect to the dimensionless spacing (S/D), peaking at S/D = 2. By introducing burning rate ratios under different flame merging states, a burning rate increment prediction model was developed. Simultaneously, it was observed that the radiative heat flux presented a rising-then-falling trend along the vertical height. To simplify computational complexity, an optimized multi-point source method was proposed to predict the external radiation. This method modeled the continuous and intermittent flames as a cuboid and a triangular prism, respectively. The total quantity of point sources was determined by discretizing the flame length at intervals of pool width. The point source numbers for continuous and intermittent flames were calculated via volume proportions.
开阔地两种不同宽高比矩形火焰燃烧速率及辐射换热试验研究
可燃液体燃料在泄漏或容器破裂时可形成不等多池火灾,燃烧剧烈,传热高。了解此类火灾的燃烧速率和辐射传热机制并建立预测模型对于加强化学工业的热管理至关重要。本研究使用两个不相等的矩形池火(长边比1:1至1:4),最近的长边间距为0-100 cm来模拟相关的不对称情景。结果表明:随着池距的增大,火焰倾斜角呈现先增大后减小的非单调趋势;与大型水池相比,小型水池的带气能力较弱,在两火源间负压的影响下,火焰倾斜角的变化更为明显。两池燃烧速率随无量纲间距(S/D)呈抛物线趋势,在S/D = 2处达到峰值。通过引入不同火焰融合状态下的燃烧速率比,建立了燃烧速率增量预测模型。同时,辐射热流密度沿垂直高度呈先上升后下降的趋势。为了简化计算复杂度,提出了一种优化的多点辐射源预测方法。该方法将连续火焰和间歇火焰分别建模为长方体和三角棱镜。点源的总数量是通过在池宽的间隔上离散火焰长度来确定的。通过体积比例计算连续和间歇火焰的点源数。
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
CiteScore
10.30
自引率
13.50%
发文量
1319
审稿时长
41 days
期刊介绍: International Journal of Heat and Mass Transfer is the vehicle for the exchange of basic ideas in heat and mass transfer between research workers and engineers throughout the world. It focuses on both analytical and experimental research, with an emphasis on contributions which increase the basic understanding of transfer processes and their application to engineering problems. Topics include: -New methods of measuring and/or correlating transport-property data -Energy engineering -Environmental applications of heat and/or mass transfer
×
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:604180095
Book学术官方微信