Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires

In this work, the effect of various exhaust parameters on the smoke propagation laws under the multi-point centralized exhaust mode are investigated through numerical simulations. The research variables include heat release rate (HRR), exhaust volume, vent spacing, and total area of open vents. Resu...

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Main Authors: Houlin Ying, Weibing Jiao, Zhisheng Xu, Jiaming Zhao, Zihan Yu
Format: Article
Language:English
Published: Elsevier 2025-02-01
Series:Case Studies in Thermal Engineering
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Online Access:http://www.sciencedirect.com/science/article/pii/S2214157X24017623
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author Houlin Ying
Weibing Jiao
Zhisheng Xu
Jiaming Zhao
Zihan Yu
author_facet Houlin Ying
Weibing Jiao
Zhisheng Xu
Jiaming Zhao
Zihan Yu
author_sort Houlin Ying
collection DOAJ
description In this work, the effect of various exhaust parameters on the smoke propagation laws under the multi-point centralized exhaust mode are investigated through numerical simulations. The research variables include heat release rate (HRR), exhaust volume, vent spacing, and total area of open vents. Results show that increasing the exhaust volume decreases the maximum temperature rise (ΔTmax), while increasing the other three factors increases the maximum temperature rise. The longitudinal temperature of the smoke below the tunnel ceiling shows an exponential decay. The exhaust vent velocity is influenced by the exhaust fan, exhibiting an W-shaped distribution. Moreover, the exhaust efficiency of the system improves with increasing extracted volume, but decreases as HRR, vent spacing, and total area of open vents increase. Eventually, the predictive model for the dimensionless back-layering length under multi-point centralized smoke extraction was developed through theoretical analysis. The results indicate that the backflow length becomes larger with increasing HRR, while it decreases with the increase in the other three variables. The results can provide a reference for understanding the smoke behavior under multi-point centralized smoke exhaust, and offer guidance for smoke control, determination of safe evacuation zones, and firefighting rescue.
format Article
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institution Kabale University
issn 2214-157X
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publishDate 2025-02-01
publisher Elsevier
record_format Article
series Case Studies in Thermal Engineering
spelling doaj-art-ca61047810e84c76a10deb191547f4f12025-02-02T05:27:17ZengElsevierCase Studies in Thermal Engineering2214-157X2025-02-0166105731Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel firesHoulin Ying0Weibing Jiao1Zhisheng Xu2Jiaming Zhao3Zihan Yu4School of Civil Engineering, Central South University, Changsha, 410075, ChinaSchool of Civil Engineering, Central South University, Changsha, 410075, China; Corresponding author.School of Civil Engineering, Central South University, Changsha, 410075, ChinaChina Academy of Building Research Fire Institute, Beijing, 100013, ChinaSchool of Civil Engineering, Central South University, Changsha, 410075, ChinaIn this work, the effect of various exhaust parameters on the smoke propagation laws under the multi-point centralized exhaust mode are investigated through numerical simulations. The research variables include heat release rate (HRR), exhaust volume, vent spacing, and total area of open vents. Results show that increasing the exhaust volume decreases the maximum temperature rise (ΔTmax), while increasing the other three factors increases the maximum temperature rise. The longitudinal temperature of the smoke below the tunnel ceiling shows an exponential decay. The exhaust vent velocity is influenced by the exhaust fan, exhibiting an W-shaped distribution. Moreover, the exhaust efficiency of the system improves with increasing extracted volume, but decreases as HRR, vent spacing, and total area of open vents increase. Eventually, the predictive model for the dimensionless back-layering length under multi-point centralized smoke extraction was developed through theoretical analysis. The results indicate that the backflow length becomes larger with increasing HRR, while it decreases with the increase in the other three variables. The results can provide a reference for understanding the smoke behavior under multi-point centralized smoke exhaust, and offer guidance for smoke control, determination of safe evacuation zones, and firefighting rescue.http://www.sciencedirect.com/science/article/pii/S2214157X24017623Tunnel fireMulti-point centralized smoke exhaustSmoke propagation characteristicsExhaust efficiencyBack-layering length
spellingShingle Houlin Ying
Weibing Jiao
Zhisheng Xu
Jiaming Zhao
Zihan Yu
Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
Case Studies in Thermal Engineering
Tunnel fire
Multi-point centralized smoke exhaust
Smoke propagation characteristics
Exhaust efficiency
Back-layering length
title Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
title_full Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
title_fullStr Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
title_full_unstemmed Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
title_short Study on smoke spreading behavior under multi-point centralized smoke extraction in tunnel fires
title_sort study on smoke spreading behavior under multi point centralized smoke extraction in tunnel fires
topic Tunnel fire
Multi-point centralized smoke exhaust
Smoke propagation characteristics
Exhaust efficiency
Back-layering length
url http://www.sciencedirect.com/science/article/pii/S2214157X24017623
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AT weibingjiao studyonsmokespreadingbehaviorundermultipointcentralizedsmokeextractionintunnelfires
AT zhishengxu studyonsmokespreadingbehaviorundermultipointcentralizedsmokeextractionintunnelfires
AT jiamingzhao studyonsmokespreadingbehaviorundermultipointcentralizedsmokeextractionintunnelfires
AT zihanyu studyonsmokespreadingbehaviorundermultipointcentralizedsmokeextractionintunnelfires