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arXiv · 2103.07925

An SPH framework for fluid-solid and contact interaction problems including thermo-mechanical coupling and reversible phase transitions

Sebastian L. Fuchs·Christoph Meier·Wolfgang A. Wall·Christian J. Cyron
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Abstract

The present work proposes an approach for fluid-solid and contact interaction problems including thermo-mechanical coupling and reversible phase transitions. The solid field is assumed to consist of several arbitrarily-shaped, undeformable but mobile rigid bodies, that are evolved in time individually and allowed to get into mechanical contact with each other. The fluid field generally consists of multiple liquid or gas phases. All fields are spatially discretized using the method of smoothed particle hydrodynamics (SPH). This approach is especially suitable in the context of continually changing interface topologies and dynamic phase transitions without the need for additional methodological and computational effort for interface tracking as compared to mesh- or grid-based methods. Proposing a concept for the parallelization of the computational framework, in particular concerning a computationally efficient evaluation of rigid body motion, is an essential part of this work. Finally, the accuracy and robustness of the proposed framework is demonstrated by several numerical examples in two and three dimensions, involving multiple rigid bodies, two-phase flow, and reversible phase transitions, with a focus on two potential application scenarios in the fields of engineering and biomechanics: powder bed fusion additive manufacturing (PBFAM) and disintegration of food boluses in the human stomach. The efficiency of the parallel computational framework is demonstrated by a strong scaling analysis.

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Sebastian L. Fuchs, Christoph Meier, Wolfgang A. Wall, Christian J. Cyron. 2021-03-14. An SPH framework for fluid-solid and contact interaction problems including thermo-mechanical coupling and reversible phase transitions. https://doi.org/10.1186/s40323-021-00200-w

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