关键词: 挡烟垂壁, 无量纲温度, 空气卷吸, 长通道, 衰减系数

Abstract: In order to improve the smoke blocking performance, and reveal the role of smoke barrier in smoke control of long channel, numerical simulations were carried out. The distribution of hot smoke temperature near the ceiling was studied with the distance between smoke barrier and fire source being 4.2, 6, 9 and 12 m, respectively, as well as the height of the smoke barrier varying within the range of 0-0.9 m. A longitudinal temperature distribution predictory formula was obtained for smoke flow in downstream of smoke barrier through the data fitting method. The formula was validated by 1∶5 scale channel fire experiments. Results show that the influences of the smoke barrier on the attenuation of the smoke temperatures in the upstream and downstream are respectively slow attenuation and accelerated attenuation, that with the increase of the barrier height, the temperature rise increases in the upstream region, while decreases in the downstream region, that height of the smoke barrier and the attenuation rate of the downstream temperature has a linear relationship, that the farther away from the fire source, the larger the dangerous range of high temperature smoke will be, and that the formula prediction results conform with the temperature data measured, which demonstrates the effectiveness of the reliability of the simulation model.

Key words: smoke barrier, dimensionless temperature, air entrainment, long channel, attenuation coefficient