Nonvolatile ultrafine particles observed to form trimodal size distributions in non-road diesel engine exhaust

Heino Kuuluvainen, Panu Karjalainen, Erkka Saukko, Teemu Ovaska, Katriina Sirviö, Mari Honkanen, Miska Olin, Seppo Niemi, Jorma Keskinen, Topi Rönkkö

Research output: Contribution to journalArticleScientificpeer-review

17 Citations (Scopus)
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Some recent findings regarding the negative health effects of particulate matter increase the relevance of the detailed characteristics of particulate emissions from different sources and especially the nonvolatile fraction of particles. In this study, the nonvolatile fraction of ultrafine particulate emissions from a non-road diesel engine was studied. The measurements were carried out in an engine laboratory and the exhaust sample was taken from the engine-out location with various steady state driving modes. Four different fuels, including fossil fuel, soybean methyl ester (SME), rapeseed methyl ester (RME), and renewable paraffinic diesel (RPD), were used. In the sampling system, the sample was diluted and led through a thermodenuder removing the volatile fraction of particles. The measured particle size distributions of nonvolatile particles were found to be trimodal. Based on the size distribution data as well as the morphology and elemental composition of particles in transmission electron microscopy (TEM) samples, we were able to draw conclusions from the most probable origin of the different particle modes, and the modes were named accordingly. From larger to smaller in particle size, the modes were a soot mode, lubricating oil originated core (LC) mode, and a fuel originated core (FC) mode. All of these three modes were detected with every driving mode, but differences were seen, for example, between different fuels. In addition, a trade-off was observed in the concentrations of the LC mode and the soot mode as a function of the engine torque.

Original languageEnglish
Pages (from-to)1345-1358
Number of pages14
JournalAerosol Science and Technology
Issue number11
Publication statusPublished - 31 Jul 2020
Publication typeA1 Journal article-refereed


  • Matti Maricq

Publication forum classification

  • Publication forum level 1

ASJC Scopus subject areas

  • Environmental Chemistry
  • General Materials Science
  • Pollution


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