摘要
为弥补常规组合式喷头存在的挡烟空隙不足,在普通7N喷头的基础上改进,设计出一种侧喷式7N喷头,并开展了数值模拟研究。通过对比下游截面处CO总质量通量、流场分布以及温度的变化情况,验证了改进喷头挡烟的有效性。在此基础上,分析了改进喷头在不同火源功率、流量、粒径下的作用效果。结果表明,普通喷头形成的雾幕能够有效降低通道温度,但并不能阻隔CO的扩散。在同样条件下,改进后的雾幕能够有效抑制CO蔓延,降温能力也有所提高,且其作用效果随喷头流量的增大更加显著。在流量为11.42 L/min时,下游CO质量通量及最高温度较改进前分别降低了71.64%、30.05%;即使火源功率增大至5 MW,改进后的雾幕仍能有效限制CO扩散;总体来看,粒径对CO的阻挡影响并不明显,对2 MW火灾的降温效果也在粒径200 m时达到最佳。
In order to make up for the deficiency of smoke blocking gap in conventional multi-orifice nozzle,a side-spray 7-orifice nozzle is designed based on the improvement of the conventional 7-orifice nozzle.By comparing the of CO mass flux at the downstream section,flow field and temperature distribution,the effectiveness of the improved nozzle in smoke blocking is verified.On this basis,the effects of the improved nozzle on CO blocking and cooling un-der different HRR,flow rate and particle size are analyzed.The results show that the water mist curtain(WMC)for-med by the conventional nozzle can effectively reduce the temperature of the channel,but can not prevent the CO dif-fusion.Under the same conditions,the improved WMC can effectively inhibit the spread of CO,and the cooling ability is also improved.Its effect is more significant with the increase of nozzle flow.When the flow rate is 11.42 L/min,the downstream CO flux value and maximum temperature are reduced by 71.64%and 30.05%respectively.Even if the HRR is increased to 5 MW,the improved WMC can still effectively limit CO diffusion.In general,the effects of par-ticle size on CO blocking is not obvious,and the cooling effect of 2 MW reaches the best when particle size is 200 m.
作者
梁天水
侯钰
LIANG Tianshui;HOU Yu
出处
《工业安全与环保》
2024年第1期1-6,共6页
Industrial Safety and Environmental Protection
基金
国家自然科学基金(51874258)。
关键词
组合式喷头
喷头流量
粒径
CO
温度
multi-orifice nozzle
nozzle flow
diameter of particles
CO
temperature
作者简介
梁天水(1981-),男,博士,教授,主要从事细水雾灭火技术研究。E-mail:liangtsh@zzu.edu.cn。
