机械排烟与细水雾对综合体控火效率的影响

Influence of Mechanical Smoke Extraction and Water Mist on Fire Control Efficiency of Complex

商业综合体作为新型特殊建筑,火灾荷载呈现平面分布,在原来羽流的基础上,火势横向、竖向迅速扩展,使其空间防火措施变得极其重要。本文研究高压细水雾与机械排烟两种防水措施,结果表明,机械排烟对于较远处的温度具有明显控制作用,平均温度较高压细水雾降低46.43%,高压细水雾对于火源附近的温度具有可观的控制效果,温度下降87.14%。机械排烟和细水雾单独作用,火源附近平均浓度降低91.15%,而共同作用下,抵消或减弱了单独作用的负面效应,温度和浓度可控制在指标之内,但两者开启时间须尽量相近且在火灾轰然之前。基于此,本文提出等效应力来解释等强度机械排烟与高压细水雾的相互作用。

As a new special building,the fire load of commercial complex is distributed in plane.On the basis of the original plume,the fire expands rapidly in horizontal and vertical direction,so the space fire prevention measures are extremely important.In this paper,the effects of high pressure water mist and mechanical smoke exhaust are studied.The results show that the mechanical smoke exhaust has obvious control effect on the distant temperature,and the average temperature is 46.43%lower than that of high pressure water mist.The high pressure water mist has considerable control effect on the temperature near the fire source,and the temperature drops by 87.14%.The average concentration near the ignition source was reduced by 91.15%by the two actions alone.Under the combined action of mechanical smoke exhaust and water mist,the negative effect of the single action is offset or weakened.The temperature and concentration are controlled within the index,and the opening time of the two is as close as possible and before the fire.The"equivalent stress"is put forward to explain the interaction between the mechanical smoke exhaust and the high pressure water mist.