不同通风模式下隧道酒精池火热传递过程

为分析不同通风模式对于池火热传递过程的影响,在隧道模型内进行直径0.5 m酒精池火实验,测试和对比燃料质量损失速率、火场温度、火焰辐射热和对流换热热通量.结果表明:在0.5 m/s纵向排烟模式下,旺盛阶段连续火焰区火焰辐射热通量比自然通风条件增加了30%左右,这对火灾热传递过程控制不利.在0.8,1 m/s纵向排烟条件下,旺盛阶段连续火焰区火焰辐射热通量及上部热烟气层温度显著降低.0.5 m/s顶部排烟显著降低了旺盛阶段连续火焰区火焰辐射热通量,火灾最晚达到旺盛阶段,较早进入衰减阶段.0.5 m/s顶部排烟是本实验条件下最佳的排烟模式.

Heat Transfer Process of Ethanol Pool Fire Under Different Ventilation Conditions in Tunnel

To analyze the effect of various ventilation modes on heat transfer process of pool fire， fire tests in 0.5m diameter ethanol pool were conducted in the tunnel model. Mass loss rate of fire source， fire temperature field， radiation and convection heat flux of flame were measured and analyzed. The results showed that 0.5m/s longitudinal smoke discharge plays a negative role in the control of fire heat transfer process， the radiant heat flux of persistent flame at the developed stage of fire is 30% bigger than that under natural ventilation condition. Under 0.8，1m/s longitudinal smoke discharge conditions， the radiant heat flux of the persistent flame and the upper smoke layer temperature decreased significantly at the developed stage of fire. 0.5m/s top smoke discharge mode significantly reduced the radiant heat flux of persistent flame， in which fire precedes into the strong stage at the latest and into the decay stage earlier. 0.5m/s top smoke discharge is the most premium ventilation mode.