19th WORLD CONFERENCE OF THE ASSOCIATED RESEARCH CENTRES FOR THE URBAN UNDERGROUND SPACE, Belgrade, Serbia, November 4-7, 2025. (Paper No: 4.6.69, pp. 705-712)
АУТОР(И) / AUTHOR(S): Andrei Danilov, Vladimir Chizhikov
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DOI: 10.46793/ACUUS2025.4.6.69
САЖЕТАК / ABSTRACT:
The issue of ensuring safe evacuation conditions from underground structures of subways, railway, and road tunnels remains relevant, as evidenced by statistical data on fires at these facilities. One of the key factors determining human safety in emergencies is the high efficiency and reliability of tunnel ventilation systems during fire emergency modes.
The aim of this work is a comparative analysis of the efficiency of smoke exhaust valves with different orientations relative to the tunnel axis (longitudinal and transverse arrangement) and the development of an optimal activation algorithm for tunnel ventilation devices based on the obtained results, considering various tunnel gradients and distances between smoke valves. Given the significant cost and complexity of full-scale experiments, the research was conducted using developed CFD models implemented in the Fire Dynamics Simulator (FDS) program. The tunnel section model used for numerical experiments consists of a computational domain including a 700-meter-long tunnel section of constant cross-section with variable gradient sections, a fire source, and variable-geometry smoke exhaust valves ensuring the required exhaust flow rate of combustion products. To ensure stable ventilation, the computational domain is connected to two tunnel sections of identical cross-section, modeled using a combined scheme with HVAC elements.
The results of the computational experiments demonstrate a significant (over twofold) increase in smoke extraction efficiency, measured by the reduction in the smoke-filled zone length, when using transversely oriented smoke exhaust valves compared to the longitudinal valve arrangement scheme. The simulation results enable the selection of an optimal activation algorithm for the tunnel ventilation system during a tunnel fire, considering the fire source location and the gradient of the emergency tunnel section, using an addressable fire alarm system.
КЉУЧНЕ РЕЧИ / KEYWORDS:
tunnel fire, tunnel ventilation, smoke exhaust duct, smoke exhaust valve, smoke-filled zone
ПРОЈЕКАТ / ACKNOWLEDGEMENT:
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