摘要
为研究大型火灾的远程扑救问题,以1.7 m×1.8 m×180.0 m的混凝土结构为隧道实体模型,分别研究5、40μm的冷气溶胶灭火剂在无火源释放后的运动过程,研究其弥漫特性与淹没效果。磷酸二氢铵的质量流速为3.5 kg/s,空气的速度为3 m/s。运用Gambit建模,以ANSYS 15.0开展数值模拟研究,与试验结果进行对比分析。结果表明:冷气溶胶灭火剂的颗粒粒径影响隧道内不同位置处的微粒浓度;灭火剂粒径越小,其在狭长隧道前端的浓度越低,而在隧道后端的浓度越高;模拟时灭火剂的平均粒径越小,其浓度误差越低,并且模拟能检测到更低数量级的微粒浓度。
In order to study the long-range fire-fighting problem of large-scale fires, the concrete structure of 1.7 m × 1.8 m × 180.0 m was used as the real type tunnel, and the motion processes of 5 and40 μm cold aerosol fire extinguishing agents after no fire source release was studied, and the diffuse features and the inundation effect were studied too. The mass flow of ammonium dihydrogen phosphate was 3.5 kg/s, the air speed was 3 m/s. Gambit was used to model and numerical simulation was carried out by ANSYS15.0. The simulation results were compared with the experimental results. The simulation results showed that the particle size of the cold aerosol fire extinguishing agent affected the concentration of particles at different locations in the tunnel. The smaller the particle size of the fire extinguishing agent was, the lower the concentration on the front of the narrow tunnel and the higher the concentration at the rear of the tunnel would be. The smaller the average particle size of the extinguishing agent was, the lower the concentration error would be. Moreover, the simulation could detect particle concentration with lower order.
引文
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