评估用于描述飞机和其他扩散火焰燃烧气溶来源的细颗粒物排放的方法
Robert Giannelli1, Jeffrey Stevens1, John S Kinsey2
1U. S. Environmental Protection Agency, Office of Transportation and Air Quality, National Vehicle and Fuels Emissions Laboratory, Ann Arbor, MI, 48105, USA.
Journal of aerosol science
|May 16, 2024
概括
这项研究比较了来自各种燃烧来源的非挥发性颗粒物 (nvPM) 排放. 结果显示不同测量方法之间的一致性,但突出显示了黑碳比率和粒子组成的来源依赖的变化.
科学领域:
- 环境科学与工程环境科学与工程
- 气溶科学与技术 气溶科学与技术
- 燃烧科学 燃烧科学
背景情况:
- 来自飞机采样系统 (ARP6320A) 的非易失性颗粒物 (nvPM) 测量的变化需要进一步调查.
- 扩散火焰燃烧气溶源 (DFCAS) 产生具有不同特征的粒子,影响测量准确性.
研究的目的:
- 为了比较来自各种DFCAS的nvPM排放,包括柴油发动机和燃气轮机.
- 根据参考方法评估不同黑碳 (BC) 质量分析仪的性能.
- 描述粒子特性 (大小,形态,组成) 以及它们对测量变异性的影响.
主要方法:
- 使用多个DFCAS进行了两个测试活动 (VARIAnT 3和4).
- 采用了三种不同的BC质量分析仪:微烟雾传感器 (MSS),空腔减弱相位转移 (CAPS PMSSA) 监控器和LII-300.
- 使用元素碳 (EC) 的参考热光学方法和总PM的重力测量分析;通过SMPS TSI,EEPS TSI和Cambustion DMS 500进行颗粒大小测量;通过miniSPLAT进行单颗粒分析.
主要成果:
- MSS和CAPS PMSSA显示与EC参考质量约20%的一致性,独立于校准源.
- 在对轮燃烧源进行校准时,LII-300的测量结果与参考EC更接近 (18-27%的差异).
- 根据来源,BC与EC的比率有所不同,与颗粒大小和形态相关;在燃气轮机排放中观察到更大,更密集的颗粒 (OC,灰),影响单散射白度.
结论:
- 不同的nvPM测量技术之间存在协议,但源特性显著影响BC测量.
- 校准源的选择对LII-300的准确性至关重要;轮机燃烧源可以提高结果.
- 燃气轮机排放量比假设更为异质,含有超出纯BC的更大颗粒,影响气溶的整体性质.
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