Effect of Outdoor Wind on the Efficiency of Mechanical Smoke Exhaust in High-rise Building Fires

2nd International Symposium on Resource Exploration and Environmental Science

生态环境科学

Xia, Letian^1 ; Zhou, Ru^1 ; He, Jiapeng^1 ; Zhu, Dezhi^2

Nanjing Tech University, Nanjing

210000, China^1

Nanjing Municipal Fire Brigade, Nanjing

210009, China^2

关键词: CO2 concentration;    Exponential growth;    High rise building;    High-rise building fire;    Mechanical exhaust systems;    Mechanical smoke exhaust;    Nanjing;    Wind speed;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/170/3/032150/pdf
DOI  :  10.1088/1755-1315/170/3/032150

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

In this paper, in order to analyze the effect of the outdoor wind on the efficiency of the mechanical exhaust system in high-rise building fires, a 15-floor high-rise building with a long corridor in Nanjing was studied. FDS (Fire Dynamic Simulation) was used to analyze the effect of different smoke exhaust models under the influence of outdoor wind. Without the outdoor wind, the CO2 concentration in the corridor was 3080ppm, natural smoke exhaust model could meet the need for evacuation. When the outdoor wind speed was 2.4m/s, the CO2 concentration in the corridor was 5042ppm, which was unable to meet the need for evacuation. Thus additional mechanical exhaust system was necessary to add for reducing the CO2 concentration in the corridor. Because the outdoor wind speed showed exponential growth with height increased, the CO2 concentration in the corridor increased with height of fire floor under the same mechanical exhaust system. The smoke exhausting volume should be redesigned, because the traditional mechanical exhaust system was unable to guarantee the people to escape safely when the fire floor was on the 12th floor or above.