Investigation and Modeling of the Magnetic Nanoparticle Aggregation with a Two-Phase CFD Model

Abstract

In this paper the magnetic nanoparticle aggregation procedure in a microchannel in the presence of external magnetic field is investigated. The main goal of the work was to establish a numerical model, capable of predicting the shape of the nanoparticle aggregate in a magnetic field without extreme computational demands. To that end, a specialized two-phase CFD model and solver has been created with the open source CFD software OpenFOAM. The model relies on the supposed microstucture of the aggregate consisting of particle chains parallel to the magnetic field. First, the microstructure was investigated with a micro-domain model. Based on the theoretical model of the particle chain and the results of the micro-domain model, a two-phase CFD model and solver were created. After this, the nanoparticle aggregation in a microchannel in the field of a magnet was modeled with the solver at different flow rates. Measurements with a microfluidic device were performed to verify the simulation results. The impact of the aggregate on the channel heat transfer was also investigated.

An in silico model of the capturing of magnetic nanoparticles in tumour spheroids in the presence of flow

“…According to Furlani and Ng (2006), Keaveny and Maxey (2008), Han et al (2010), Khashan et al (2011), Woińska et al (2013 and Barrera et al (2021), the inter-particle forces are negligible when the nanoparticles have a distance of more than three particle diameters, which we assume to be the case here and thus neglect the interparticle forces, similar to Boutopoulos et al (2020). However, nanoparticles are known to form aggregates, e.g., chains (Pálovics et al, 2020), and in such cases, the inter-particle forces indeed play a significant role. In this context, Cregg et al (2009) and Cregg et al (2010) studied nanoparticle agglomeration with a particle-based approach, including the inter-particle forces for a small number of particles (up to 25).…”

Magnetically Agitated Nanoparticle-Based Batch Reactors for Biocatalysis with Immobilized Aspartate Ammonia-Lyase

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