Optimization of Ventilation Mode of Smoke Control System in High-rise Building Fire

In high-rise building fire, a large amount of fresh air will be pressurized into the fire floor when smoke ventilation and prevention system is used. The fresh air dilutes the smoke, but it also reduces the efficiency of mechanical exhaust. The assumption that vertical composition smoke control model (air curtain combined with pressurization and exhaust fan) is put forward. The mathematic model of smoke flow in high-rise building and κ-ε three-dimension turbulence model with two equations are used, and the influences of smoke exhaust effect with different smoke control modes are analyzed. The simulation and experiments results show that: in strip corridor, air curtain can effectively prevents the smoke moving into the atria, but the smoke control time is short relatively. While using air curtain combined with positive pressure, the smoke control time at least has an increase of 60s, and the vertical composition smoke control model has the same effect as atria pressurization model, but the volume of fresh air has decreased by 1/3.