铜导线短路迸溅熔珠对粉状α-纤维素的引燃能力  

Ignition Ability of Powdered α-Cellulose by Splashing Melted Beads Resulting from Copper Wire Short Circuit

作　　者：雷心怡 LEI Xinyi(Yangling Demonstration Area Fire and Rescue Division,Yangling,Shaanxi Province 712100,China)

机构地区：[1]杨凌示范区消防救援支队,陕西杨凌712100

出　　处：《中国人民警察大学学报》2022年第10期30-36,共7页Journal of China People's Police University

摘　　要：短路迸溅熔珠可携带高温飞行至短路点较远处,其在带电火灾现场塌落堆积层中经常可见,对起火点及起火原因的认定有证明和指向作用。相较于线端短路熔痕,迸溅熔珠要经历产生、飞行、落地多个过程,导致其本身运动轨迹的不确定性,给分析带来较大困难。研究了铜导线短路迸溅熔珠产生及飞行过程对其引燃能力及金相组织特征的影响。通过对短路电弧能量、熔珠直径和引燃情况进行统计,得到引燃边界条件和引燃概率,并对不同引燃情况的熔珠金相组织进行观察分类。研究发现:影响短路迸溅熔珠引燃能力的决定性因素为熔珠直径;引燃迸溅熔珠的典型金相组织有四类,非引燃迸溅熔珠的典型金相组织有三类。Splashing melted beads with high temperature can fly far away from the short circuit point. It is often seen in the collapse accumulation layer at the electrical fire scene, which provides evidence and shows direction in the identification of fire point and fire cause. Unlike the short circuit melted marks at the end of the wire, the splashing bead goes through multiple processes of generation, flight and landing, which leads to the uncertainty of its own trajectory and brings great difficulties to the research. This paper studies the generation and flight process of short circuit splashing beads, and its ignition ability and metallographic structure characteristics. The ignition boundary conditions and bead ignition probability are obtained through the statistics of short circuit arc energy, bead diameter and ignition situation, and the metallographic structure of the molted bead under different ignition situations is observed and classified. It is found that: the decisive factor affecting the ignition ability of short circuit splashing bead is the bead diameter;there are four kinds of typical metallographic structures of the splashing melted bead capable of causing ignition and three kinds of typical metallographic structures of splashing melted bead incapable of causing ignition.

关 键 词：短路迸溅熔珠 电弧能量 引燃边界 金相组织 

分 类 号：TU998.1[建筑科学—市政工程] X928.7[环境科学与工程—安全科学]