Hysteretic dynamics of phase interfaces in bilinear forward-backward diffusion equations

Michael Herrmann; Dirk Janßen

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arXiv · 2404.13592

Hysteretic dynamics of phase interfaces in bilinear forward-backward diffusion equations

Michael Herrmann·Dirk Janßen

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Abstract

We study single-interface solutions to a free boundary problem that couples bilinear bulk diffusion to the Stefan condition and a hysteretic flow rule for phase boundaries. We introduce a time-discrete approximation scheme and establish its convergence in the limit of vanishing step size. The main difficulty in our proof are strong microscopic oscillations which are produced by a propagating phase interface and need to be controlled on the macroscopic scale. We also present numerical simulations and discuss the link to the viscous regularization of ill-posed diffusion equations.

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Michael Herrmann, Dirk Janßen. 2024-04-21. Hysteretic dynamics of phase interfaces in bilinear forward-backward diffusion equations. https://arxiv.org/abs/2404.13592

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