(333d) Modelling Particle Aggregation and Breakage in Suspensions By Coupled CFD-DEM
AIChE Annual Meeting
Tuesday, November 15, 2022 - 1:30pm to 1:50pm
In this work, two numerical models, Discrete Element Method (DEM) and Computational Fluid Dynamics (CFD), were coupled to simulate the effect of shear and pH on aggregate dynamics in suspension. This simulation describes the motion of particles and fluid, particle-particle interaction, and particle-fluid interaction. The structural properties of aggregates (cumulative size distribution, fractal dimensions, average size, etc.) were determined when the aggregate dynamics reached a stable condition in the simulation. Accordingly, a higher shear rate increases the chances of particle collision, but also leads to faster aggregate breakage, in agreement with Kushimoto et al. (2020). Aggregates with higher fractal dimension have a dense, spherical-like structure with more neighbour particles, and are much harder to break into smaller fragments.
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Kushimoto, K.; Ishihara, S.; Pinches, S.; Sesso, M. L.; Usher, S. P.; Franks, G. V.; Kano, J., Development of a method for determining the maximum van der Waals force to analyze dispersion and aggregation of particles in a suspension. Advanced Powder Technology 2020, 31 (6), 2267-2275.