Verdugo Ignacio, Cruz Juan José, Álvarez Emilio, Reszka Pedro, Figueira da Silva Luís Fernando, Fuentes Andrés
Departamento de Industrias, Universidad Técnica Federico Santa María, Av. España 1680, Casilla 110-V, Valparaiso, Chile.
Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Santiago, Chile.
Sci Rep. 2020 Jul 9;10(1):11364. doi: 10.1038/s41598-020-68256-z.
Soot emissions from flaming combustion are relevant as a significant source of atmospheric pollution and as a source of nanomaterials. Candles are interesting targets for soot characterization studies since they burn complex fuels with a large number of carbon atoms, and yield stable and repeatable flames. We characterized the soot particle size distributions in a candle flame using the planar two-color time-resolved laser induced incandescence (2D-2C TiRe-LII) technique, which has been successfully applied to different combustion applications, but never before on a candle flame. Soot particles are heated with a planar laser sheet to temperatures above the normal flame temperatures. The incandescent soot particles emit thermal radiation, which decays over time when the particles cool down to the flame temperature. By analyzing the temporal decay of the incandescence signal, soot particle size distributions within the flame are obtained. Our results are consistent with previous works, and show that the outer edges of the flame are characterized by larger particles ([Formula: see text]), whereas smaller particles ([Formula: see text]) are found in the central regions. We also show that our effective temperature estimates have a maximum error of 100 K at early times, which decreases as the particles cool.
明火燃烧产生的烟尘排放是大气污染的重要来源以及纳米材料的一个来源。蜡烛是烟尘特性研究的有趣对象，因为它们燃烧含有大量碳原子的复杂燃料，并产生稳定且可重复的火焰。我们使用平面双色时间分辨激光诱导白炽（2D - 2C TiRe - LII）技术对蜡烛火焰中的烟尘粒径分布进行了表征，该技术已成功应用于不同的燃烧应用，但此前从未用于蜡烛火焰。烟尘颗粒通过平面激光片加热到高于正常火焰温度的温度。炽热的烟尘颗粒发射热辐射，当颗粒冷却到火焰温度时，热辐射会随时间衰减。通过分析白炽信号的时间衰减，可获得火焰内的烟尘粒径分布。我们的结果与先前的研究一致，表明火焰的外边缘以较大颗粒（[公式：见原文]）为特征，而较小颗粒（[公式：见原文]）则出现在中心区域。我们还表明，我们的有效温度估计在早期的最大误差为100 K，随着颗粒冷却误差会减小。
