Comparison of methods to derive morphological parameters of multi-fractal samples of particle aggregates from TEM images

M. Wozniak (1) , F. R. A. Onofri (1) , S. Barbosa (2) , Jerôme Yon (3) , J. Mroczka

1 IUSTI - Institut universitaire des systèmes thermiques industriels
2 EM2C - Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion
3 CORIA - Complexe de recherche interprofessionnel en aérothermochimie

We investigate two main methods for detecting correlations between the size and fractal dimension of small particle aggregates from two-dimension Transmission Electron Microscopy (TEM) images. The first method is based on a multi-scale analysis of an entire aggregate sample, whereas the second method (modified Box-Counting algorithm, MBC) is based on the analysis the self-similarity properties of each aggregate within a sample. Both methods were tested on a sample of soot aggregates as well as synthetic TEM images produced with a tuneable Diffusion Limited Aggregation code. We have found that the MBC method provides a less noisy estimation for the evolution of the fractal dimension with the size of aggregates, giving at the same time a criterion to reject the aggregates with insufficient self-similarity properties. So that with this method, the mean fractal dimension of the soot sample was found to be much lower (1.66 +/- 0.02) than that derived with the classical multi-scale analysis (1.88 +/- 0.02). Published by Elsevier Ltd.

Domaines: Physique [physics]

M. Wozniak, F. R. A. Onofri, S. Barbosa, Jerôme Yon, J. Mroczka. Comparison of methods to derive morphological parameters of multi-fractal samples of particle aggregates from TEM images. Journal of Aerosol Science, 2012, 47, pp.12-26. ⟨10.1016/j.jaerosci.2011.12.008⟩. ⟨hal-01459971⟩