An experiment and simulation of smoke confinement utilizing an air curtain

• A air curtain is researched in building fire accident and the protected zone is the stairwell.
• It brings a clear different perspective between the air curtain and the hung wall.
• The influence of the internal factors is clear, which is helpful to provide guild for the designers.

Smoke is one of the most important cause of casualties and controlling its diffusion is particular significant during a fire accident. In this paper, experiment and numerical simulation were conducted to study the efficacy of air curtain to confine fire-induced smoke transportation in a high-rise building. The experiment was conducted on a reduced scale building model and the simulation was conducted on a full scale building. The air curtain discharge velocity, the different efficacy of smoke confinement between hung wall and air curtain, as well as the dimension of air curtain outlets were discussed.According to experiment results, air curtain played a good role on controlling smoke diffusion and the discharge velocity could influence the efficacy of air curtain. Complementary numerical simulation was conduced and the simulation result agreed well with the experiment data. When the value of heat release rate (HRR) and the breadth of air curtain outlet (B) were kept constant, the different discharge velocities had different influence on the efficacy of the air curtain and an appropriate velocity was obtained. The different breadths of the outlets had disproportionate levels of influence on confining smoke diffusion and a suitable range of the breadth was proposed. When the breadth was in the proposed range, the air curtain could already play a good role in the confine of smoke diffusion. At the same time, the decrease of CO concentration was more apparent than that when the value of the breadth was not in the proposed range.