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arXiv · 2408.16449

A Non-Isothermal Phase-Field Crystal Model with Lattice Expansion: Analysis and Benchmarks

Maik Punke·Marco Salvalaglio·Axel Voigt·Steven M. Wise
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Abstract

We introduce a non-isothermal phase-field crystal model including heat flux and thermal expansion of the crystal lattice. The thermal compatibility condition, as well as a positive entropy-production property, is derived analytically and further verified by numerical benchmark simulations. Furthermore, we examine how the different model parameters control density and temperature evolution during dendritic solidification through extensive parameter studies. Finally, we extend our framework to the modeling of open systems considering external mass and heat fluxes. This work sets the ground for a comprehensive mesoscale model of non-isothermal solidification including thermal expansion within a positive entropy-producing framework, and provides a benchmark for further meso- to macroscopic modeling of solidification.

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Maik Punke, Marco Salvalaglio, Axel Voigt, Steven M. Wise. 2024-08-29. A Non-Isothermal Phase-Field Crystal Model with Lattice Expansion: Analysis and Benchmarks. https://doi.org/10.1088/1361-651x/ada784

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