Bai Zhenpeng
Zhengzhou Key Laboratory of Electric Power Fire Safety, College of Building Environment Engineering, Zhengzhou University of Light Industry, 450000, China.
Heliyon. 2024 Jan 22;10(3):e25103. doi: 10.1016/j.heliyon.2024.e25103. eCollection 2024 Feb 15.
Power cables consist of insulation, padding and sheathing, which are highly susceptible to ignition. Power cables are an important factor affecting fire risk in urban utility tunnels (UUTs). In this paper, the combustion characteristics of four types of power cables (YJV, ZR-YJV, ZR-VV, and ZR-PE) in UUTs were investigated using a cone calorimeter. In this paper, laboratory experiments were conducted to investigate the combustion characteristics of power cables with two different parameters including two heat fluxes (35 kW/m and 75 kW/m) and two sheath thicknesses (3 mm and 5 mm). The effects of heat release rate (HRR), effective heat combustion (EHC), optical density index (ODI) and smoke production rate (SPR) on ignition and combustion were investigated. The results showed that ZR-VV power cables have lower TTI, lower average HRR, lower EHC, higher MLR, and lower SEA than YJV and ZR-YJV power cables.With a conical calorimeter and heat flux of 35 kW/m, the HRR of the power cables increased within 200 s, while for ODI, the total smoke output of ZR-YJV cables was minimized. Heat flux has a significant effect on HRR, SPR and EHC of ZR-PE cable. Sheath thickness has little effect on HRR, SPR and EHC of ZR-PE cables. In addition, one of the most important parameters, the ignition time, which depends on the composition and structure of the cable, was identified. Finally, the effect of external heat flux is complex and depends on the combustion characteristics of the power cable. Laboratory tests provide useful information for understanding the combustion behavior of power cables, including heat release rate, effective thermal burn, optical density index, and smoke production.
电力电缆由绝缘层、填充层和护套组成，极易着火。电力电缆是影响城市公用隧道（UUT）火灾风险的一个重要因素。本文利用锥形量热仪研究了UUT中四种类型电力电缆（YJV、ZR - YJV、ZR - VV和ZR - PE）的燃烧特性。本文进行了实验室实验，以研究具有两个不同参数的电力电缆的燃烧特性，这两个参数包括两个热通量（35kW/m和75kW/m）以及两个护套厚度（3mm和5mm）。研究了热释放速率（HRR）、有效热燃烧（EHC）、光密度指数（ODI）和产烟速率（SPR）对着火和燃烧的影响。结果表明，与YJV和ZR - YJV电力电缆相比，ZR - VV电力电缆具有更低的点燃时间（TTI）、更低的平均HRR、更低的EHC、更高的质量损失速率（MLR）和更低的比消光面积（SEA）。在锥形量热仪和35kW/m的热通量条件下，电力电缆的HRR在200s内增加，而对于ODI，ZR - YJV电缆的总烟雾输出最小。热通量对ZR - PE电缆的HRR、SPR和EHC有显著影响。护套厚度对ZR - PE电缆的HRR、SPR和EHC影响很小。此外，确定了最重要的参数之一——着火时间，它取决于电缆的组成和结构。最后，外部热通量的影响是复杂的，并且取决于电力电缆的燃烧特性。实验室测试为理解电力电缆的燃烧行为提供了有用信息，包括热释放速率、有效热燃烧、光密度指数和产烟情况。
