地下商业街火灾烟气流动实验研究

烟气是火魔的杀手锏。在不同火源功率的长通道实体火灾实验基础上,研究地下商业街吊顶装修前后,以及不同的补风与排烟条件下烟气的特点,考察防排烟措施启动时机、启动位置以及排烟量的大小。实验结果表明:安装天花板有利于提高排烟速率,但烟气蔓延速度加快,因此宜采用镂空式天花板以利用顶部蓄烟;地下商业街宜采用远火源端补风、近端机械排烟方式,设计中需依据风量和速率选取风机,还应考虑风机对流场的扰动以及进风口设置位置。

Experimental Study on the Fire Smoke Flow in Underground Business Street

Smoke is the killer of fire. On the basis of full-scale practical fire experiments in a long channel under different power, the characters of smoke are studied in underground business street fires before and after ceiling decoration and under different air-supplement and exhaust conditions. The start-up time, the location and exhaust magnitude of the fans are also observed. Though the ceiling decoration contributes to smoke exhaustion, the experiment results show that the smoke flow would accelerate, so pierced ceiling would be suitable for storing up the smoke. Air-supplement remote from the fire origin and mechanical exhaust near the origin are proposed in underground business street. The fans should be selected according to smoke quantity as well as the exhaust rate in the design. The turbulence of flow distribution caused by the fans and the installment location of the air intake also should be under consideration when doing mechanical exhaust.