比较FDS和FLUENT在池火灾模拟中的应用

Comparison of FDS and FLUENT applied in pool fire simulation

热辐射是池火灾燃烧的主要危害之一,可能导致人员伤亡或设备设施损坏。油罐火灾是典型的池火灾。本文通过对无风情况下油罐火灾火焰形状进行理论模型分析,建立了各自的物理模型和几何模型。应用计算流体动力学软件Fluent和火灾动力学模拟软件FDS,对无风情况下池火灾对周围大气环境的热辐射强度进行模拟,得到了火焰周围入射热流密度分布图,运用软件Sta-tistica拟合得出热辐射强度与距离火焰中心的水平距离的对应关系,分别计算出轻伤半径区域下的最小安全距离。数值模型模拟结果与池火灾经验模型进行比较,发现FDS辐射强度结果与经验模型结果吻合较好。分析了利用这两种模型模拟油罐火灾各自的优点和缺点,最后提出了运用FDS软件模型模拟油罐火灾时的优势。

Thermal radiation is a key hazard characteristic of pool fire, which may result in injury to people and damage to adjacent equipment and facilities. The tank fire is a typical kind of the pool fire. Some theoretic supposi- tions and analysis about the flame shape of tank fire without wind were carried out in this paper. Also the physical and geometrical to the shape were established. The heat radiation to environment from the pool fire were thereby nu- merical simulated by using software Fluent of Computational Fluid Dynamics and Fire Dynamics Simulation soft- ware, to obtain the density distribution diagram of incident heat flow around the flame. The software Statistica was used to fit the relationship between heat radiation intensity and horizontal distance to the center of flame, then cal- culate the minimum safety interval under the minor injuries radius of the area. By comparing with the empirical models, the presented results of FDS appeared to be quite good. The calculation methods of the two models were further analyzed to find the advantages and disadvantages of then when being used in simulating oil tank fires. Fi- nally, it was concluded that FDS has more advantages than Fluent with satisfactory results.