排烟口设计对排烟效果影响的研究

The Study of the Influence Exerted by the Design of Smoke Extractor on Smoke Extraction Effect

排烟口是火灾发生时烟气排出的出口,排烟口高度和位置对排烟效果具有重要影响。运用FDS数值模拟方法,以实验台为依据建立数值模型,针对排烟口高度和排烟口位置的改变对排烟效果的影响进行分析,结果表明:随着排烟口高度的升高,各种排烟风速下的排烟效果都得到了改善。在排烟口风速较高的情况下,排烟口的高度变化对烟气溢出厚度的影响更大,采用大风速的控烟效果要优于小风速。侧排方式的排烟效果低于顶排方式,远壁排烟方式要优于近壁排烟方式。

A smoke extractor is the exit where the smoke goes out during a fire. The height and position of a extractor have crucial influences on the smoke extraction effect. Nevertheless, at present there are no specific smoke regula tions on the height and position of a smoke extractor. By using the method of numerical simulation in FDS, by estab- lishing the the change numerical model based on the experiment station and analyzing the smoke extraction effect influenced by of the height and position of a smoke extraction, the results have been obtained that with the increasing of the height of a smoke extractor, the smoke extraction effect will be improved in any ventilation rate. When the venti- lation rate in a smoke extractor is relatively high, the change of the height of a smoke extractor has bigger influence on the smoke overflow thickness, while a large ventilation rate has better effect than small ventilation rate on smoke control. A side extraction doesn＇ t work as well as a top extraction, and extraction at the far wall is better than at the near.