Study on Vertical Combination Smoke Control Model in High-rise Building Fire

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