CFD-based fire spread visualization for improvement of road tunnel safety

Teaching and training of operators of road and highway tunnels are necessary to increase their preparedness for incidents accompanied by fire and ensure safe tunnel operation. For such purposes Tunnel Traffic & Operation Simulator (TTOS) is used in Slovakia. TTOS is capable to simulate various types of emergency situations in 1 km long twin tube virtual highway tunnel with longitudinal ventilation including scenarios of car accidents accompanied by fire. However, TTOS does not provide information about the fire dynamics and smoke stratification. In this paper, the use of the well-known CFD-based Fire Dynamics Simulator for creating a series of didactic videos is illustrated. The videos demonstrate the smoke propagation and time evolution of temperature, air flow velocity and visibility for selected fire scenarios. They have been implemented into the TTOS environment and became available for tunnel operators.