Measurements and scaling of buoyancy-induced flows in ventilated tunnels

We investigate the ventilation conditions required to control propagation of smoke, produced by a tunnel fire, in presence two inertial forcings: transverse extraction system and longitudinal flow. For that purpose, we performed series experiments reduced-scale tunnel, using mixture air helium simulate release hot smoke during fire. Experiments were designed focus on flows allow buoyant be confined between adjacent vents. Different source conditions, terms density velocity release, analysed along with different vent configurations. allowed us quantify increase needed confine overcoming effect an imposed velocity. Vents rectangular shape, spanning over whole width, provide best performance. Finally, studied stratification flow, individuating four regimes. Interestingly, when fade out, as both flow vertical increase, dynamics becomes almost independent forcing induced which eventually acts passive scalar transported