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arXiv · 2507.14149

Integral fractional viscoelastic models in SPH: LAOS simulations versus experimental data

Luca Santelli·Adolfo Vázquez-Quesada·Aizeti Burgoa·Aitor Arriaga·Rikardo Hernandez·Marco Ellero
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Abstract

The rheological behaviour of a polymer was investigated by performing numerical simulations in complex flow and comparing them to experiments. For our simulations, we employed a Smoothed Particle Hydrodynamics scheme, utilizing an integral fractional model based on the K-BKZ framework. The results are compared with experiments performed on melt-state isotactic polypropylene under medium and large amplitude oscillatory shear. The numerical results are in good agreement with the experimental data, and the model is able to capture and predict both the linear and the non-linear viscoelastic behaviours of the polymer melt. Results show that equipping SPH with an integral fractional model is promising approach for the simulation of complex polymeric materials under realistic conditions.

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Luca Santelli, Adolfo Vázquez-Quesada, Aizeti Burgoa, Aitor Arriaga, Rikardo Hernandez, Marco Ellero. 2025-07-03. Integral fractional viscoelastic models in SPH: LAOS simulations versus experimental data. https://arxiv.org/abs/2507.14149

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