Typical and Atypical Morphology of Non-volatile Particles from a Diesel and Natural Gas Marine Engine
Typical and Atypical Morphology of Non-volatile Particles from a Diesel and Natural Gas Marine Engine
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DOI：
10.4209/aaqr.2020.01.0006
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发表时间：
2020-04-01
影响因子：
4
通讯作者：
Rogak, Steven
中科院分区：
文献类型：
--
作者：
Baldelli, Alberto;Trivanovic, Una;Rogak, Steven
利用透射电镜（TEM）研究了柴油和天然气掺烧柴油引燃气时柴油机非挥发性颗粒物的排放特性。最常见的颗粒（数量> 95%）是烟灰聚集体。当使用柴油和NG燃料时，这些“典型”聚集体对于100 nm聚集体分别表现出20.7 +/-1.9和26.9 +/-1.7的初级颗粒直径。高度不均匀的聚集体，具有不同的较小和较大的单体组，在所有样品中可见，但最常见于高负荷下的柴油燃料。所观察到的“典型”颗粒包括超聚集体、小型致密聚集体、球体、矿物状多面体颗粒和纤维。这种颗粒虽然罕见（通过对所有收集的图像中描述的每种类型的颗粒数量进行计数计算，平均为3%），但在大多数样品中发现，并且可能是由各种机制产生的。例如，球体（直径约300 nm）最有可能来自润滑油中的金属。
Non-volatile particle emissions from a marine engine fueled by either diesel or natural gas (NG) blended with diesel pilot gas were investigated via transmission electron microscopy (TEM). The most common particles (> 95% by number) were soot aggregates. These "typical" aggregates exhibited primary particle diameters of 20.7 +/- 1.9 and 26.9 +/- 1.7 for 100 nm aggregates when diesel and NG fuel were used, respectively. Highly non-uniform aggregates, with distinct groups of smaller and larger monomers, were visible in all of the samples but occurred most frequently with diesel fueling at high loads. The observed "a typical" particles included super-aggregates, small compact aggregates, spheres, mineral-like polyhedral particles, and fibers. Such particles, although rare (averaging 3% by number, as calculated by counting the number of particles for each type depicted in all of the collected images), were found in most of the samples and could have been produced by a variety of mechanisms. For instance, the spheres (approximately 300 nm in diameter) most likely arose from metals within the lubricating oil.