排烟口设计对排烟效果影响的研究

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。

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

A smoke extractor is the exit where the smoke goes out during a fire.The height and position of a smoke extractor have crucial influences on the smoke extraction effect.Nevertheless,at present there are no specific regulations on the height and position of a smoke extractor.By using the method of numerical simulation in FDS,by establishing the numerical model based on the experiment station and analyzing the smoke extraction effect influenced by the change 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 ventilation 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.