城市地下道路V形区段坡度构成对烟气扩散和重点排烟效果的影响研究

Study on influence of slope composition at V-shaped section of urban underground road on smoke diffusion and point smoke exhaust effect

为了研究城市地下道路V形区段坡度构成对烟气扩散和重点排烟效果的影响,采用数值模拟手段,对V形区段内变坡点两侧不同坡度构成、排烟口的开启方式对烟气扩散和重点排烟效率的影响进行研究。研究结果表明:对于对称V形区段,采用重点排烟控制烟气相对容易,但对降低排烟道下方顶棚最高温度作用有限;针对非对称V形区段,烟气的自由扩散特性与变坡点两侧坡度差有关,增加大坡度侧的排烟口数量可以提高排烟效率,但要将烟气有效地控制在较小的范围内相对困难。实际运行中,应结合坡度的实际构成和烟气控制总目标,制定相应的排烟口开启策略。

The influence of different slope composition on both sides of slope change point and opening mode of smoke exhaust port on smoke diffusion and point smoke exhaust efficiency in tje V-shaped section of urban underground road was discussed by means of numerical simulation.The results showed that in the symmetrical V-shaped section,using the point smoke exhaust to control the smoke was relatively easy,but the effect on reducing the maximum ceiling temperature under the smoke exhaust duct was limited.In the asymmetric V-shaped section,the free diffusion characteristics of smoke were related to the slope difference on both sides of slope change point,and increasing the number of smoke exhaust vents on the side with large slope could improve the smoke exhaust efficiency,but it was relatively difficult to effectively control the smoke in a smaller range.In actual operation,the corresponding opening strategy of smoke exhaust vents should be formulated according to the actual composition of slope and the overall goal of smoke control.