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arXiv · 2512.05785

Feasibility study for physics-informed direct numerical simulation describing particle suspension in high-loaded compartments of air-segmented flow

Otto Mierka·Raphael Münster·Henrik Julian Felix Bettin·Kerstin Wohlgemuth·Stefan Turek
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Abstract

The Archimedes Tube Crystallizer (ATC) employs air-segmented flow in coiled tubes to achieve narrow residence time distributions for continuous crystallization. Taylor and Dean vortices drive particle suspension in this system. However, one-way coupled models fail to capture the fluid-particle feedback that becomes critical at higher loadings. We present a particle-resolved Direct Numerical Simulation (DNS) framework based on a Finite Element-Fictitious Boundary Method with hard-contact modeling of particle interactions. Simulations of L-alanine suspensions across varying particle sizes, solid contents, and rotational speeds are validated against experimental side-view imaging. Three quantitative metrics-axial distribution, radial index, and vertical asymmetry-are introduced to classify suspension regimes. The DNS results reproduce the experimentally observed flow map zones (green, yellow, red/yellow, red) and resolve subtle transitions such as rear loading and loss of vertical symmetry. This feasibility study demonstrates that DNS can reliably predict dense suspension behavior and provides a mechanistic foundation for crystallizer design.

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Otto Mierka, Raphael Münster, Henrik Julian Felix Bettin, Kerstin Wohlgemuth, Stefan Turek. 2025-12-05. Feasibility study for physics-informed direct numerical simulation describing particle suspension in high-loaded compartments of air-segmented flow. https://arxiv.org/abs/2512.05785

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