Bihałowicz Jan Stefan, Rogula-Kozłowska Wioletta, Krasuski Adam, Majder-Łopatka Małgorzata, Walczak Agata, Fliszkiewicz Mateusz, Rogula-Kopiec Patrycja, Mach Tomasz
Institute of Safety Engineering, The Main School of Fire Service, 52/54 Słowackiego Street, 01-629 Warsaw, Poland.
Faculty of Safety Engineering and Civil Protection, The Main School of Fire Service, 52/54 Słowackiego Street, 01-629 Warsaw, Poland.
Materials (Basel). 2021 Dec 26;15(1):152. doi: 10.3390/ma15010152.
This study aimed to determine the relative densities of populations of particles emitted in fire experiments of selected materials through direct measurement and parametrization of size distribution as number (NSD), volume (VSD), and mass (MSD). As objects of investigation, four typical materials used in construction and furniture were chosen: pinewood (PINE), laminated particle board (LPB), polyurethane (PUR), and poly(methyl methacrylate) (PMMA). The NSD and VSD were measured using an electric low-pressure impactor, while MSD was measured by weighing filters from the impactor using a microbalance. The parametrization of distributions was made assuming that each distribution can be expressed as the sum of an arbitrary number of log-normal distributions. In all materials, except PINE, the distributions of the particles emitted in fire experiments were the sum of two log-normal distributions; in PINE, the distribution was accounted for by only one log-normal distribution. The parametrization facilitated the determination of volume and mass abundances, and therefore, the relative density. The VSDs of particles generated in PINE, LPB, and PUR fires have similar location parameters, with a median volume diameter of 0.2-0.3 µm, whereas that of particles generated during PMMA burning is 0.7 µm. To validate the presented method, we burned samples made of the four materials in similar proportions and compared the measured VSD with the VSD predicted based on the weighted sum of VSD of raw materials. The measured VSD shifted toward smaller diameters than the predicted ones due to thermal decomposition at higher temperatures.
本研究旨在通过对选定材料火灾实验中排放的颗粒群的数量分布（NSD）、体积分布（VSD）和质量分布（MSD）进行直接测量和参数化，来确定其相对密度。作为研究对象，选取了建筑和家具中使用的四种典型材料：松木（PINE）、层压刨花板（LPB）、聚氨酯（PUR）和聚甲基丙烯酸甲酯（PMMA）。NSD和VSD使用低压冲击器进行测量，而MSD则通过用微量天平称量冲击器上的过滤器来测量。分布的参数化是基于这样的假设进行的，即每个分布都可以表示为任意数量的对数正态分布的总和。在所有材料中，除了松木，火灾实验中排放的颗粒分布是两个对数正态分布的总和；在松林中，分布仅由一个对数正态分布构成。参数化有助于确定体积和质量丰度，进而确定相对密度。在松木、层压刨花板和聚氨酯火灾中产生的颗粒的VSD具有相似的位置参数，中位体积直径为0.2 - 0.3 µm，而在聚甲基丙烯酸甲酯燃烧过程中产生的颗粒的中位体积直径为0.7 µm。为了验证所提出的方法，我们以相似的比例燃烧了由这四种材料制成的样品，并将测量的VSD与基于原材料VSD的加权总和预测的VSD进行了比较。由于在较高温度下的热分解，测量的VSD向比预测值更小的直径方向偏移。
