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arXiv · 2110.01340

Approximation of multiphase mean curvature flows with arbitrary nonnegative mobilities

Eric Bonnetier·Elie Bretin·Simon Masnou
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Abstract

This paper is devoted to the robust approximation with a variational phase field approach of multiphase mean curvature flows with possibly highly contrasted mobilities. The case of harmonically additive mobilities has been addressed recently using a suitable metric to define the gradient flow of the phase field approximate energy. We generalize this approach to arbitrary nonnegative mobilities using a decomposition as sums of harmonically additive mobilities. We establish the consistency of the resulting method by analyzing the sharp interface limit of the flow: a formal expansion of the phase field shows that the method is of second order. We propose a simple numerical scheme to approximate the solutions to our new model. Finally, we present some numerical experiments in dimensions 2 and 3 that illustrate the interest and effectiveness of our approach, in particular for approximating flows in which the mobility of some phases is zero.

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Eric Bonnetier, Elie Bretin, Simon Masnou. 2021-10-04. Approximation of multiphase mean curvature flows with arbitrary nonnegative mobilities. https://arxiv.org/abs/2110.01340

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