大气压力对火灾烟气影响的数值模拟

The Numeral Imitation of the Influence of the Atmospheric Pressure on Fire Smoke

对环境大气压力不同的室内火灾分别进行了数值模拟,得到了两种环境条件下的火源热释放速率、温度、烟粒子浓度、CO浓度的变化数据,并对模拟结果进行了详细的分析与比较。研究结果表明:大气压力较低的地区,发生火灾时,燃烧不充分,热释放速率的两个峰值相距较近,稳定燃烧阶段短;烟气温度比常压地区低;烟粒子浓度变化不明显;CO浓度明显大于常压地区,因此烟气的毒性是低压地区威胁室内人员生命安全的重要因素。

The room fire is simulated in different atmospheric pressure conditions respectively, and the results are gained about the changing data of HRR, temperature, density of fume particle, and the density of carbon monoxide under these two different environments. Then detailed analysis and comparison on the results are made. The results shows that, in the area of low atmospheric pressure, when a fire occurs, it doesn＇ t burn fully, the two peak values of HRR are close, the steady burning process is short; the temperature of the flue gas is lower than that in a normal atmosphere state; the differences of the density of gas particle is small; the density of carbon monoxide is obviously larger than that in a normal atmosphere state. Therefore, the toxicity of the gas is an important element that threatens the life security of the people in the area of low atmospheric pressure.