纵向风对隧道柴油池火影响的试验研究

Experimental studies on the effect of longitudinal wind on diesel pool fires in tunnel

在全尺寸隧道模型中开展了试验研究,采用柴油池火设计了2.8~12.2 MW共8组工况,考查了油盘面积2~5 m^2、纵向风速0.2~2.0 m/s条件下隧道火灾烟气层形态、热释放速率和火源燃烧速率的变化规律。研究发现,各工况在该区域附近的烟气分层效果较好,纵向风速对各工况中火源区烟气分层影响不明显。热释放速率经验计算值比测量值普遍高7%~30%,但当火源面积较大、纵向风速较高时经验计算值显著低于测量值。火源平均燃烧速率表现出与热释放速率一致的变化规律,随隧道纵向风速增大而增大。在纵向风作用下,3 m^2和5 m^2柴油池火的燃烧速率比无风环境下分别高出18.4%和25.1%。

This research carried out 8 fire tests whh HRRs ranging from 2.8-12.2MW using diesel pool fire in a full scale tunnel, with the purpose of invesligating the variations of smoke layering, heat release rate and fuel burning rate under conditions of 0.2-2.0 m/s longitudinal wind velocities and 2-5 m^2 pool sizes. Resulls showed thai smoke in the near fire region demonstrated good slrati fication while longitudinal wind seemed to impose non-significant influence. Empirical prediction values of HRR were generally 7%-30% higher than the measured values, with the exception of two tests where fire sizes were large and longitudinal wind velocities were high. Burning rates showed consistent behaviors with HRRs which increased with longitudinal velocities. The burning rates for 3 m^2 and 5 m^2 pool fires with longitudinal wind were 18.4% and 25.1% higher respectively than values in quiescent condilions.