不同布置形式下的桥架电缆燃烧特性  

Combustion characteristics of trays cable in different layouts

作　　者：陈长坤[1] 徐童 陈杰[1] 左博元 CHEN Changkun;XU Tong;CHEN Jie;ZUO Boyuan(Institute of Disaster Prevention Science and Safety Technology,Central South University,Changsha 410075,China)

机构地区：[1]中南大学防灾科学与安全技术研究所,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2022年第11期4326-4334,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金重大项目(72091512);湖南创新型省份建设专项经费资助项目(2020SK2004);中南大学研究生自主探索创新项目(2021zzts0234,2021zzts0221)。

摘　　要：电缆一般是以成束的形式来敷设,同时多集中布置在墙壁附近以及顶棚下方等特殊空间,如电缆隧道、电缆沟、厂房等,这使得电缆桥架火灾在上述特殊环境下往往表现出较为复杂的蔓延行为,同时,电缆燃烧火焰及其形成的熔滴会对附近结构造成破坏,具有较大的危险性。为此,本文以单排桥架电缆为研究对象,分析不同布置间距以及贴壁情况下的电缆燃烧特征。研究结果表明:堆叠、紧密及不同间距(10,20和30 mm)工况下的电缆火蔓延平均速率依次降低;电缆燃烧熔滴质量以及热释放速率平均值和最高值均随电缆间距增加而减小;侧壁和顶板均可以通过影响电缆燃烧火焰的空气卷吸量或热反馈效应而加快电缆燃烧过程,其中,“侧壁+顶板”组合限制条件对电缆燃烧的促进程度最大。Cables are generally laid in bundles, and they are mostly concentrated in special locations near walls and under the ceiling, such as cable tunnels, cable trenches, and factory buildings, and therefore, trays cable fires are affected by special environments, and usually show more complicated fire spread behavior. At the same time,the nearby structures will be destroyed by the cable burning flame and the molten droplets formed, which is very dangerous. Based on this, single-row tray cable was taken as the research object, and the cable fire and combustion characteristics in the layout space and wall-attached environment were studied. The results show that the average fire spread rate under the conditions of stacking, tightness, different spacings(10, 20 and 30 mm) decreases,respectively. The mass of the burning droplets of the cable and the average and the maximum value of the heat release rate decrease with the increase of the cable spacing. Both the side wall and the top plate can increase the cable burning by influencing the thermal feedback effect of the thermal effect and the air entrainment. Among them, the "side wall+ceiling" combination restriction condition promotes the cable burning the most.

关 键 词：桥架电缆 燃烧特性 火蔓延速率 热释放速率 

分 类 号：X934[环境科学与工程—安全科学]