The major challenge of the post-processing of soot aggregates in transmission electron microscope (TEM) images is the detection of soot primary particles that have no clear boundaries, vary in size within the fractal aggregates, and often overlap with each other. In this study, we propose an automated detection code for primary particles implementing the Canny Edge Detection (CED) and Circular Hough Transform (CHT) on pre-processed TEM images for particle edge enhancement using unsharp filtering as well as image inversion and self-subtraction. The particle detection code is tested for soot TEM images obtained at various ambient and injection conditions, and from five different combustion facilities including three constant-volume combustion chambers and two diesel engines. Through a comparison between automatically detected and manually selected primary particles from extensive datasets, five key image-processing parameters of the self-subtraction level, negative Laplacian shape parameter, maximum and minimum diameter of primary particles, and CHT sensitivity are optimised. From the analysis of the size distribution and mean diameter of primary particles, it is found that the automatic method is much more dependent upon the minimum primary particle diameter and CHT sensitivity than the other three parameters. With the optimised set values, the new particle detection code shows a good agreement with the results from the manual method.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Automated Detection of Primary Particles from Transmission Electron Microscope (TEM) Images of Soot Aggregates in Diesel Engine Environments


    Additional title:

    Sae Int. J. Engines


    Contributors:

    Conference:

    JSAE/SAE 2015 International Powertrains, Fuels & Lubricants Meeting ; 2015


    Published in:

    Publication date :

    2015-09-01


    Size :

    18 pages




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Morphology Analysis of Wall-Deposited Diesel Soot Particles via Transmission Electron Microscope

    Takahashi, Junya / Kondo, Katsufumi / Aizawa, Tetsuya | SAE Technical Papers | 2014


    Soot Removal from Diesel Engine Lubrication Systems

    Cheekala, Nageswara R. / Unger, Peter / Rohrbach, Ronald | SAE Technical Papers | 2010


    Transmission Electron Microscopy of Soot Particles Directly Sampled in Diesel Spray Flame - A Comparison between US#2 and Biodiesel Soot

    Aizawa, T. / Nishigai, H. / Kondo, K. et al. | British Library Conference Proceedings | 2012


    Soot emission from a direct injection diesel engine

    Lee,S. / Shin,D. / Lee,J. et al. | Automotive engineering | 2004


    Soot Emission from a Direct Injection Diesel Engine

    Shin, Dongheun / Lee, Jeongmin / Sung, Nakwon et al. | SAE Technical Papers | 2004