A New Investigation on Tunnel Pool Fire Phenomenon Using CFD Technique

In this study, the amount of generated pool fire, as a result of the release of chemicals in the case of an accident in tunnels, was simulated and the results were compared to the experimental data. At first, various amounts of spatial resolution (R*) were considered to compare the existing experimental data at different heights at the upstream, downstream and above the pool fire. The comparison studies showed that both numerical predictions and experimental measurements were, in general, comparable. Furthermore, FDS code was used to simulate the tunnel fire scenario for both cases of natural and forced ventilation. The grid using in the simulations is assessed by cells with the optimal spatial resolution and the influence of the ventilating systems on pool fire dynamic and its development was investigated. As a consequence, the temperature profile, O2, CO2, and visibility were compared in the two cases. These results showed that the ventilation system plays an important role in both fire development and heat removal by providing a safely evacuate rout in the tunnel.