火灾流场中湍流、燃烧和浮力的相互作用

Turbulence and Combustion Models Used in Simulating Compartmental Fire with Buoyancy Effect

对国际标准化组织 (ISO) 1997年发布的火灾试验房间尺寸和火灾释热速率进行了数值研究 ,主要针对火位源于房间中间和里侧一个角落两种情况进行了数值模拟。在数值模拟中 ,燃烧反应被看成在一个大容积内进行 ,而不是仅在薄层的反应区。在大容积燃烧中 ,燃烧属于层流还是湍流取决于燃料和空气在该位置的比例。火灾流场中浮力作用下的预混、半预混和非预混燃烧是采用EDC模拟和k-ε双方程湍流模型。最后通过对数值模拟结果的分析 ,讨论了火灾流场中湍流、燃烧和浮力的相互作用。

The room dimension and fire heat release rate issued by International Standardization Organization in 1997 are researched for two cases one is a fire right at the center of the room while the other is a fire at the corner of the room. During the simulation, the combustion is regarded as in a big cubage, and whether it is laminar combustion or turbulent combustion lies on the ratio of fuel to air. The EDU model and k-ε two equations turbulent model are used to simulate the premix, half premix and un-premix combustion with buoyancy effect. At last, the effect of turbulence and combustion models used in simulating compartmental fire with buoyancy is discussed. The work in this paper is important to large scale ISO fire test.