Soot particle size distribution measurements in a turbulent ethylene swirl flame
Soot particle size distribution measurements in a turbulent ethylene swirl flame
复制标题
DOI：
10.1016/j.proci.2020.06.212
复制
发表时间：
2021-04-10
影响因子：
3.4
通讯作者：
Mastorakos, Epaminondas
中科院分区：
文献类型：
--
作者：
De Falco, Gianluigi;El Helou, Ingrid;Mastorakos, Epaminondas
有必要从理论、实践甚至监管的角度更好地理解湍流火焰的粒径分布（psd）。在二次（稀释）空气喷射的非预混涡流乙烯火焰上进行了实验，研究了用扫描迁移率粒度仪（SMPS）测量的排气和燃烧器内psd以及用消光测量的烟尘体积分数（fv）。研究的重点是了解系统地改变稀释空气喷射的数量和位置对燃烧器内和排气口的psd和fv的影响。psd还与平面激光诱导白炽灯（LII）进行了比较。LII提供了一些关于不同流动条件下相对烟尘量和空间分布的补充信息，有助于解释结果。对于没有空气稀释的火焰，fv沿着燃烧器的中心线向排气方向逐渐下降，PSD显示从大颗粒到小颗粒的转变。然而，随着空气的稀释，f v在稀释射流与燃烧器轴接触处急剧减小。稀释射流的下游f v逐渐减少，psd保持不变，直到排气。在排气处，没有空气稀释的火焰比有空气稀释的火焰显示出明显更多的颗粒，其fv比有空气稀释的火焰大一到两个数量级。该数据集提供了与不同稀释参数的燃气轮机燃烧相关的湍流火焰中的烟尘空间和粒径分布以及稀释对粒径的影响的见解。此外，这项工作使用非原位和原位技术测量fv，并强调了在两者之间比较结果的困难。这些结果对验证紊流燃烧的先进模型是有用的。(c) 2020燃烧研究所。Elsevier Inc.出版。版权所有。
There is a need to better understand particle size distributions (PSDs) from turbulent flames from a theoretical, practical and even regulatory perspective. Experiments were conducted on a sooting turbulent nonpremixed swirled ethylene flame with secondary (dilution) air injection to investigate exhaust and in-burner PSDs measured with a Scanning Mobility Particle Sizer (SMPS) and soot volume fractions (f v ) using extinction measurements. The focus was to understand the effect of systematically changing the amount and location of dilution air injection on the PSDs and f v inside the burner and at the exhaust. The PSDs were also compared with planar Laser Induced Incandescence (LII) calibrated against the average f v . LII provides some supplemental information on the relative soot amounts and spatial distribution among the various flow conditions that helps interpret the results. For the flame with no air dilution, f v drops gradually along the centreline of the burner towards the exhaust and the PSD shows a shift from larger particles to smaller. However, with dilution air f v reduces sharply where the dilution jets meet the burner axis. Downstream of the dilution jets f v reduces gradually and the PSDs remain unchanged until the exhaust. At the exhaust, the flame with no air dilution shows significantly more particles with an f v one to two orders of magnitude greater compared to the Cases with dilution. This dataset provides insights into soot spatial and particle size distributions within turbulent flames of relevance to gas turbine combustion with differing dilution param eters and the effect dilution has on the particle size. Additionally, this work measures fv using both ex situ and in situ techniques, and highlights the difficulties associated with comparing results across the two. The results are useful for validating advanced models for turbulent combustion. (c) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.