中庭类建筑火灾烟气流动的数值模拟

Numerical simulation of smoke movement in fires on atrium buildings

火灾场景烟气流动与控制数值模拟是性能化消防设计的关键。借助Fluent软件,考虑烟气产生量、烟气排放量两因素,设计两种中庭类建筑火灾场景,并建立数值模型。模型边界条件为:环境温度20℃,排烟口速度分别为15.741、11.111 m/s,补风口速度1.107 m/s。模拟结果表明:在火灾发生300、900 s时,两种场景在6 m处的温度场小于60℃,CO质量分数小于0.15%;900 s时烟层沉降高度分别为14.0和11.5 m,三者均符合性能化评定标准。该研究对中庭烟气控制系统的工程设计具有实用价值。

Numerical simulation of smoke movement and control in fires is a key for performance-based fire safety design.In consideration of the output and discharge of smoke,two fire scenes of buildings with atrium are designed and a numerical model is established with the help of Fluent software.The terminal conditions of the model include： ambient temperature is 20 ℃,the speed of smoke vent is 15.741 m/s and 11.111 m/s respectively,and the speed of wind compensating vent is 1.107 m/s.As a result： when fires have been on for 300 s and 900 s,the temperature field of the two scenes is lower than 60 ℃ at the height of 6 m,the mass fraction of CO is less than 0.15%;at 900 s,the smoke layer interface height is 14.0 m and 11.5 m respectively.All the three values meet performance standard.This research has practical value for engineering designs of smoke management system in atrium.