NUMERICAL FIRE SIMULATION IN SUBWAY STATION TUNNEL BY USING DIFFERENT COMBUSTION MODELS


KARAASLAN S., DİNLER N., YÜCEL N.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.26, no.3, pp.533-547, 2011 (SCI-Expanded) identifier

Abstract

In this study, a full scaled model of underground subway system station model was generated. The turbulence and combustion models avaliable in Fluent were searched for which models best suits with real experiments. It is found that SST k-omega turbulence model represents the flow more realisticly. Flow simulations on this model were conducted by using SST k-omega turbulance model for tunnel entrance velocity of 1, 3, 5 and 7 m/s. 'Non-premixed', 'eddy dissipation' and 'species Transport' combustion models avaliable in Fluent were tested for fire simulations. By comparing simulation results with the experimental and numerical data found in the literature, it is observed that the Species transport model is the more suitable than the others. The fire simulations were performed for heat realese rate of 10 MW and 50 MW fire scenarios for fuel pool located at the centre of station. The results of critical velocity, temperature and fire-induced smoke spread were compared with the experimental and numerical found in the literature. It was investigated that the backflow occrued at the station ceiling under critic ventilation velocity. Temperature distributions were very high for non-premixed and eddy dissipation combustion models except species transport model.