RT info:eu-repo/semantics/article
T1 A Discussion on the Effective Ventilation Distance in Dead-End Tunnels
A1 Pereiras, Bruno
A1 Sierra Fernández, Carlos María
A1 Miguel González, Celia
A1 García Díaz, Manuel
A2 Ingeniería CartograficaGeodesica y Fotogrametria
K1 Ingenierías
K1 Ingeniería de minas
K1 Ancillary Ventilation
K1 Effective Zone
K1 Cfds
K1 Mixture Model
AB [EN] Forcing ventilation is the most widely used system to remove noxious gases from a workingface during tunnel construction. This system creates a region near the face (dead zone), in whichventilation takes place by natural diffusion, rather than being directly swept by the air current. Despitethe extensive use of this system, there is still a lack of parametrical studies discerning the mainparameters affecting its formation as well as a correlation indicating their interrelation. With this aimin mind, computational fluid dynamics (CFDs) models were used to define the dead zone based onthe airflow field patterns. The formation of counter vortices, which although maintain the movementof air hinder its renewal, allowed us to discuss the old paradigm of defining the dead zone as a verylow air velocity zone. Moreover, further simulations using a model of air mixed with NO2 offered anidea of NO2 concentrations over time and distance to the face, allowing us to derive at a more realisticequation for the effective distance. The results given here confirm the degree of conservativism ofpresent-day regulations and may assist engineers to improve ventilation efficiency in tunnels bymodifying the duct end-to-face distance
PB MDPI
LK https://hdl.handle.net/10612/19235
UL https://hdl.handle.net/10612/19235
NO Pereiras, B.; Sierra Fernández, C. M.; Miguel González, C.; García Díaz, M. (2019). A Discussion on the Effective Ventilation Distance in Dead-End Tunnels. Energies, 12(17), https://doi.org/10.3390/EN12173352
DS BULERIA. Repositorio Institucional de la Universidad de León
RD 13-may-2024