Dust cake morphology in fibrous filtration of monodisperse particles based on fractal analysis

DOI

10.2991/icseee-15.2016.211How to use a DOI?

Keywords

Fibrous filtration; dust cake; convection-diffusion; fractal dimension

Abstract

An off-lattice Monte Carlo model has been developed to simulate growth of dust cakes from ultrafine particles in a model filter composed of an array of identical parallel fibers placed transverse to the flow. Unlike previous simulations on the dust cakes, this study considerd the effect of the flow feature in the vicinity of fibers on the morphologies of dust cakes. The flow was described by the modified Kuwabara flow field with consideration of the slip effect at fibers surface. The probability of a particle moving in four different directions was derived from the two-dimensional particle convection-diffusion-migration equation. The resulting microstructure of dust cake formed on fibrous medium was characterized by its density and fractal dimension. The dependences of the porous properties of dust cakes (density, density distribution and fractal dimension) upon the particle transport mechanisms (measured by Pelect number, Pe in this work) were also investigated. The results indicate that the dust cakes structures strongly depend on particle transport mechanism, a smaller Pe tends to give a more open and loose structure with a lower density and fractal dimension. For the case of Pe = 1, the fractal dimension for the cake structure approaches to 1.710, a value for the diffusion-limited aggregation (DLA) model. When Pe > 100, the deposition behavior is very close to the pure ballistic aggregation model (LA), and the resulting structure is on average uniform at all length scale. Furthermore, a dust layer near filtration medium with lower porosity can be observed for a higher Peclet number (Pe 10), unlike previous results on particles deposition on a simply two dimensional threadiness substrate.

Copyright

© 2016, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Shixian Wu
AU  - Hui Zhu
AU  - Can Qi
AU  - Haiming Fu
PY  - 2016/04
DA  - 2016/04
TI  - Dust cake morphology in fibrous filtration of monodisperse particles based on fractal analysis
BT  - Proceedings of the 2015 4th International Conference on Sustainable Energy and Environmental Engineering
PB  - Atlantis Press
SP  - 1186
EP  - 1192
SN  - 2352-5401
UR  - https://doi.org/10.2991/icseee-15.2016.211
DO  - 10.2991/icseee-15.2016.211
ID  - Wu2016/04
ER  -