导体材质对成束电缆竖直向上火蔓延特性影响的FDS数值分析  

Numerical analysis on the effects of conductor material on vertical upward flame spread of bundled cables by FDS

作　　者：刘雄军 奚谦逸 杨晔 凌国桢 韩啸 谢启源[2] LIU Xiongjun;XI Qianyi;YANG Ye;LING Guozhen;HAN Xiao;XIE Qiyuan(Academy of Science and Technology,Jiangsu Shangshang Cable Group Company Limited,Liyang 213300,China;State Key Laboratory of Fire Science,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]江苏上上电缆集团有限公司,溧阳213300 [2]中国科学技术大学火灾科学国家重点实验室,合肥230026

出　　处：《火灾科学(中英文)》2024年第4期214-225,共12页Fire Safety Science

基　　金：国家自然科学基金项目(52276139)。

摘　　要：综合考虑电缆性能和制造成本,铝芯和铜芯是国内外最常用的两类电缆线芯材料。长期的电缆制造设计和燃烧性能检测实践表明,在相同外部绝缘配方和结构条件下,铝芯电缆比铜芯电缆更易形成竖直向上火蔓延。采用FDS软件,构建了成束电缆竖直燃烧标准检测室的引燃与燃烧数值模型。基于GB/T 18380标准,实现了丙烷/空气预混火焰的喷射流场,火源功率约20 kW,与实验标准一致。继而针对6根直径为29 mm的典型成束电缆,详细计算了铝芯与铜芯电缆的引燃和向上蔓延燃烧过程。热释放速率、可燃气体生成速率以及内部导芯温度分布等结果表明,铝芯电缆在燃烧过程中燃烧更强烈,更易形成向上火蔓延。因此,对于铝芯阻燃电缆设计,外部护套层配方应适当增强阻燃设计,才可达到与铜芯电缆相同的防火性能。Taking into account both cable performance and manufacturing costs,aluminum and copper cores are the most commonly used conductor materials for cables.Long-term practices in cable design and combustion performance testing have shown that under the same external insulation formulations and structural conditions,cables with aluminum cores are more prone to vertical upward flame spread compared to those with copper cores.This paper utilizes the Fire Dynamics Simulator(FDS) software to construct a numerical model of ignition and combustion for a standard testing chamber of vertically burning bundled cables.Based on the GB/T 18380 standard,the injection flow field of a propane/air premixed flame was achieved with a fire source power of approximately 20 kW,consistent with experimental standards.Subsequently,for six typical bundled cables with a diameter of 29 mm each,the ignition and upward flame spread for both copper and aluminum core cables were calculated in detail.Results such as the rate of heat release,the rate of combustible gas production,and the internal conductor temperature distribution indicate that aluminum core cables burn more intensely and are more prone to upward flame spread.Therefore,for the design of flame-retardant cables with aluminum cores,the formulation of the external sheath layer should be appropriately enhanced in terms of flame retardancy to achieve the same level of fire protection as copper core cables.

关 键 词：成束电缆 向上火蔓延 铝芯电缆 铜芯电缆 数值模拟 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术] X932[自动化与计算机技术—计算机科学与技术]