净空高度为22、30 m高大空间自动喷水灭火仿真模拟

Simulation of Automatic Sprinkler Fire Extinguishing in Large Spaces with Clearance Height of 22 m and 30 m

为研究非仓库类高大净空场所自动喷水灭火系统洒水喷头相关性能对灭火效果的影响,采用火灾动力学模拟软件FDS对净空高度为22、30 m的高大空间进行了自动喷水灭火仿真模拟,给出了安全可靠的工程设计参数。结果表明,在净空高度为22 m条件下,当喷头动作温度为74℃时,控火效果较差,喷头启动的临界热释放速率为6.9 MW;当喷头动作温度为68℃时,能较快抑制火灾,喷头启动的临界热释放速率为6.2 MW。在净空高度为30 m条件下,当喷水强度为55、50 L(/min·m^(2))时,喷头启动后火灾能迅速被抑制;随着喷水强度降低,燃料堆垛烧损加重,当喷水强度为45 L(/min·m^(2))时,控火失败。因此在30 m净空高度下,当采用快速响应喷头时,推荐喷水强度应不小于55 L(/min·m^(2))。

This paper investigated the influence of sprinkler design on fire extinguishing performance of automatic sprinkler system in non‑warehouse high‑clearance places,simulated the automatic sprinkler fire extinguishing in the large spaces with clearance height of 22 m and 30 m by using fire dynamics simulation(FDS)software,and proposed the safe and reliable engineering design parameters.When the clearance height and operating temperature of the sprinkler were 22 m and 74℃,poor fire control performance was obtained,and the critical heat release rate of sprinkler starting was 6.9 MW.When the sprinkler operating temperature was 68℃,the fire could be controlled quickly,and the critical heat release rate of sprinkler starting was 6.2 MW.When the clearance height was 30 m,and the spray intensities were 55 L/(min·m^(2))and 50 L/(min·m^(2)),the fire could be quickly controlled after the sprinkler was started.The decreasing spraying intensity increased the burning loss of fuel stacking,and it was fail to control the fire when the spray intensity was 45 L/(min·m^(2)).Therefore,the spraying intensity of fast response sprinkler should not be less than 55 L/(min·m^(2))when the clearance height was 30 m.