排烟朝向对密闭机舱火灾时风机流量压力特征及排烟效果影响的计算模拟

Study on Influence of Smoke Exhaust Orientation upon the Flow and Pressure Characteristics of Fans and Smoke Exhaust Effect during Fire in a Closed Engine Room

以利用FDS+HVAC系统对某典型密闭船舶机舱及其主要设备和防排烟系统(风机、管路、节点等)进行建模,设定典型火源、排烟、补风等边界条件,开展数值模拟,分析顶吸、侧吸两种排烟模式对风机流量压力特征及排烟效果的影响,结果表明,顶吸的排烟效果优于侧吸,顶吸模式下,排烟管道内的流量更大,导致更多的烟气被排出机舱,从而使得机舱内的烟气层高度和能见度更高,CO体积浓度和温度更低。

The FDS+HVAC system was used to model the engine room,main equipment and smoke prevention and exhaust systems(fans,pipelines,nodes,etc.).By setting typical fire sources,smoke exhaust and supplementary,numerical simulations were carried out to investigate the effects of top suction and side suction smoke exhaust modes on fan flow pressure characteristics and smoke exhaust effects.The results showed that the smoke exhaust effect of top suction is better than that of side suction.In the top suction mode,the flow in the smoke exhaust duct is larger,which causes more smoke to be discharged from the cabin,thereby making the smoke layer height and visibility in the cabin better,with lower CO volume concentration and temperature.