Soft-Agglomerate Breakage by Discrete Element Method (DEM) Simulations

Nanoparticle product properties are depending on primary particle size distribution and the structure of agglomerates formed by them. The fluid flow [1] as well as particle-particle interactions determine the structure of agglomerates and their size distribution [2]. Furthermore, agglomerates of nanoparticles occupy far more volume than their equivalent sphere volume and can influence fluid-particle interactions in aerosol reactors leading to agglomerate restructuring and even gelation [3]. Many force models for weak (e.g. van-der-Waals) interparticle forces inside agglomerates in DEM simulations have been proposed. The objective of this work is to investigate the impact of process variables in such force models focusing on breakup duration and mechanism of agglomerates in shear flows.

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2. Flesch, J.C., P.T. Spicer, and S.E. Pratsinis, Laminar and turbulent shear-induced flocculation of fractal aggregates. AIChE Journal, 1999. 45(5): p. 1114-1124.

3. M.C. Heine, S.E. Pratsinis, "Brownian coagulation at high concentrations", Langmuir, 23, 9882-9890 (2007).