公共大空间建筑生化恐怖模式和通风技术分析

Analysis of Biochemical Terror Patterns and the Ventilation Technology in Public Large Space Buildings

公共大空间建筑生化恐怖模式主要有制造火灾产生毒性气体、爆炸毒气弹分散毒性物质和人工直接布洒毒性物质。分析表明:火灾烟气受热浮力作用,在建筑物上部出现明显的烟气层,采用自然或机械排烟能有效地减缓或控制烟气层下降;爆炸分散毒性物质,除了爆炸点周边区域外,毒气扩散受热气流诱导,以及浓度差引起的运动;不考虑室内对流气流的影响,人工布洒毒性物质产生的毒性气体,其扩散主要是由浓度差引起的。不同类型恐怖袭击产生的毒性气体受室内对流气流的控制,合适的通风方式能够控制毒性气体的扩散和输运过程。但能否采用某一形式的通风系统兼备防范不同类型的恐怖袭击,需要对通风系统的通风量、气流组织和控制方式做更深入的研究。

Biochemical terror patterns in public large space buildings include firing to produce poisonous gas, exploding gas bomb to spread poisonous materials and artificial distributing poisonous materials directly. The analysis showed that the fire smoke diffusion is driven by the thermodynamic buoyancy, the smokelayer obviously appears in the upside of the building, and the smoke-layer will descend slowly or be controlled by the natural ventilation or mechanical ventilation. Besides the peripheral partial region of the explosion point, for explosive gas bomb to spread poisonous materials, the diffusion of poison gas mainly attribute to the upward inducement effect of the produced hot airflow, as well as the concentration grads. Without considering the convective movement of the indoor airflow, the poison gas was produced by artificial distributing poisonous materials mainly driven by the concentration grads. For various terror attacks, the motion of poisonous gases is basically affected by the convection airflow. Therefore, appropriate ventilation method can reduce the concentration of poisonous gas, and control the diffusion and conveyance process of poisonous gas indoor. The further research on the ventilation ratio, airflow distribution and control method of ventilation system is necessary for certain ventilation system can be used for different terror attacks.