Yongil Lee1,2, Kyomin Choi1,2, Wonseog Jung1,2, Michael E. Versoza2,3, Mona Loraine M. Barabad2,3, Taesung Kim1, Duckshin Park 2 1 SungKyunKwan University, Jangan-gu, Suwon 04763, Korea
2 Korea Railroad Research Institute, Woram-dong, Uiwang 16105, Korea
3 University of Science and Technology, Yuseong, Daejeon 34113, Korea
Received:
December 5, 2017
Revised:
April 9, 2018
Accepted:
April 9, 2018
Download Citation:
||https://doi.org/10.4209/aaqr.2017.11.0439
Cite this article:
Lee, Y., Choi, K., Jung, W., Versoza, M.E., Barabad, M.L.M., Kim, T. and Park, D. (2018). Generation Characteristics of Nanoparticles Emitted from Subways in Operation.
Aerosol Air Qual. Res.
18: 2230-2239. https://doi.org/10.4209/aaqr.2017.11.0439
HIGHLIGHTS
ABSTRACT
In this study, measurements were carried out to identify the generation characteristics of wear particles emitted under a subway cabin during operation. Along with a fast mobility particle sizer, probes were installed under a subway cabin and in a subway tunnel to measure the size distributions of nanoparticles at 1-s intervals. Based on the particle density measured under the cabin minus that measured in the tunnel, the size distribution of wear particles generated under the cabin during deceleration was estimated to be bimodal at 165.5 nm and 6.98 nm. These particles were most likely generated from wheel-rail contact, as the train utilized electric braking (no mechanical force applied). In addition, a change in the wear mechanism appears to have arisen due to the increased temperature of the wheel-rail contact while nanoparticles were being emitted, leading to an initial generation of 165.5-nm particles followed by 6.98-nm particles 1 s later.
Keywords:
Nanoparticle size distribution; Urban railway; Wear particle; Wheel-rail contact.