Samuel L Manzello, Sayaka Suzuki
National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899-8665, USA.
National Research Institute of Fire and Disaster (NRIFD), Chofu, Tokyo, 182-8508, Japan.
Fuel (Lond). 2020;279. doi: 10.1016/j.fuel.2020.118507.
A shared feature in the rapid spread of large outdoor fires are the production or generation of new, far smaller combustible fragments from the original fire source referred to as firebrands. A simplified experimental protocol has been developed that allows for the study of firebrand generation processes from various structural materials exposed to an applied wind field. The influence of angle of orientation on the firebrand production process is investigated. The thickest firebrands were produced with experiments with 45° angle under 8 m/s. The influence of angle was found to have the same trend under the tested wind speeds and to be more apparent at 8 m/s than 6 m/s. As installation angles are a key factor for photovoltaic panel (PV) efficiency, often only the solar energy efficiency is considered in PV panel orientation decisions. Yet, this study demonstrates that the types of firebrands generated in the event of large outdoor fires were sensitive to the angle of installation for structural materials used as surrogates for PV panels. The work is unique in that is begins the discussion on firebrand production from cutting edge home technologies, such as PV panels. These results have implications for how installation angles may influence firebrand production in the event of large outdoor fire outbreaks.
大型户外火灾迅速蔓延的一个共同特征是,从原始火源产生或生成新的、小得多的可燃碎片,即火brand。已经开发了一种简化的实验方案,用于研究暴露在外部风场中的各种结构材料的火brand生成过程。研究了定向角度对火brand产生过程的影响。在8米/秒的风速下,45°角的实验产生了最厚的火brand。发现在测试风速下,角度的影响具有相同的趋势,并且在8米/秒时比在6米/秒时更明显。由于安装角度是光伏板(PV)效率的关键因素,在光伏板定向决策中通常只考虑太阳能效率。然而,这项研究表明,在大型户外火灾中产生的火brand类型对用作光伏板替代品的结构材料的安装角度很敏感。这项工作的独特之处在于,它开始讨论前沿家用技术(如光伏板)的火brand产生问题。这些结果对于安装角度在大型户外火灾爆发时如何影响火brand产生具有启示意义。