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Title: ASPECTS OF CRITICAL VELOCITY VARIATION FOR FIRE AND AIR POLLUTION CONTROL IN ROAD TUNNELS
ASPECTS OF CRITICAL VELOCITY VARIATION FOR FIRE AND AIR POLLUTION CONTROL IN ROAD TUNNELS

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Omar Lanchava; Giorgi Javakhishvili; Teimuraz Kunchulia; Zaza KhokeraSvili; Nino Arudashvili
10.5593/sgem2023/4.1/s19.30
10.5593/sgem2023/4.1
1314-2704
978-619-7603-59-0
English
23
4.1
•    Prof. DSc. Oleksandr Trofymchuk, UKRAINE 
•    Prof. Dr. hab. oec. Baiba Rivza, LATVIA
Air Pollution and Climate Change
Fires in road tunnels pollute the ventilation air of the underground space and create unfavorable conditions for life. International recommendations for the design of emergency ventilation share the statement that the critical velocity (specifically its numerical value of 3.0 m/s) can be used to predict the spread of toxic substances in underground space and to exclude backflow for the majority of tunnels. Nowadays, it is advisable to supplement this point of view with the results of new studies, which notes that fires in underground conditions cause a dynamic pressure higher than the pressure created by tunnel fans. Based on CFD modelling, in presented paper we found that even at a critical velocity of 4.5 m/s in inclined tunnels with a heat release rate of 50 MW, jet fans can no longer influence on the ventilation flow, since their power is limited compared to the draft caused by fire. The current paper presents the results of the research, which distinguish the cases from each other: 1. when, based on the available classical knowledge, it will be possible to develop emergency ventilation projects to save lives, and 2. when the available knowledge is no longer sufficient to realize the mentioned projects and novel study results are needed to develop a new approach to the problem.
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This work was supported by Shota Rustaveli National Science Foundation of Georgia (SRNSF) [Grant number FR-22-12 949]. Project title: “Study of critical velocity and fireinduced back-layering to save lives in road tunnels”.
conference
https://doi.org/10.5593/sgem2023/4.1/s19.30
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Proceedings of 23rd International Multidisciplinary Scientific GeoConference SGEM 2023
23rd International Multidisciplinary Scientific GeoConference SGEM 2023, 03 - 09 July, 2023
Proceedings Paper
STEF92 Technology
International Multidisciplinary Scientific GeoConference SGEM
SWS Scholarly Society; Acad Sci Czech Republ; Latvian Acad Sci; Polish Acad Sci; Russian Acad Sci; Serbian Acad Sci and Arts; Natl Acad Sci Ukraine; Natl Acad Sci Armenia; Sci Council Japan; European Acad Sci, Arts and Letters; Acad Fine Arts Zagreb Croatia; Croatian Acad Sci and Arts; Acad Sci Moldova; Montenegrin Acad Sci and Arts; Georgian Acad Sci; Acad Fine Arts and Design Bratislava; Russian Acad Arts; Turkish Acad Sci.
237-244
03 - 09 July, 2023
website
9198
Tunnel fire, Critical velocity, Backlayering, Air pollution