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arXiv · 2311.10872

An unstructured geometrical un-split VOF method for viscoelastic two-phase flows

Matthias Niethammer·Muhammad Hassan Asghar·Tomislav Maric·Dieter Bothe
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Abstract

Since viscoelastic two-phase flows arise in various industrial and natural processes, developing accurate and efficient software for their detailed numerical simulation is a highly relevant and challenging research task. We present a geometrical unstructured Volume-of-Fluid (VOF) method for handling two-phase flows with viscoelastic liquid phase, where the latter is modeled via generic rate-type constitutive equations and a one-field description is derived by conditional volume averaging of the local instantaneous bulk equations and interface jump conditions. The method builds on the plicRDF-isoAdvector geometrical VOF solver that is extended and combined with the modular framework DeboRheo for viscoelastic computational fluid dynamics (CFD). A piecewise-linear geometrical interface reconstruction technique on general unstructured meshes is employed for discretizing the viscoelastic stresses across the fluid interface. DeboRheo facilitates a flexible combination of different rheological models with appropriate stabilization methods to address the high Weissenberg number problem.

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Matthias Niethammer, Muhammad Hassan Asghar, Tomislav Maric, Dieter Bothe. 2023-11-17. An unstructured geometrical un-split VOF method for viscoelastic two-phase flows. https://doi.org/10.1016/j.cpc.2024.109475

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