Fires in tunnels: Integration of the numerical simulation in the automatic ventilation responses - Lessons drawn from the full-scale fire tests in the Mont Blanc tunnel
During a fire in a tunnel, the ventilation system appears to be only equipment able to develop an active influence on the safety level, in a positive - or a negative - manner. Thus, the operation of the system plays a major role on the safety conditions inside the tunnel. This fact has been highlighted in recent publications (AIPCR, 1999; Casale, 1999). The following presentation shows, on the basis of the practical case of the Mont Blanc tunnel refurbishment, how the numerical simulation can be used in order to study specific aspects of the ventilation control. The aim of these studies is to complete a fully automatic response aiming at controlling the favourable stratification conditions in the vicinity of the fire. The global approach is based on the use of ID models in order to dimension and simulate the longitudinal ventilation control. Some aspects linked to the stratification are studied with more accuracy, with the help of the 3D CFD models. They deal with destabilising phenomena or with complex motions showing how the stratification situation can be obtained as a result of the longitudinal ventilation active control phases.
展开▼
