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arXiv · 1710.09675

Convexity splitting in a phase field model for surface diffusion

Rainer Backofen·Steven M. Wise·Marco Salvalaglio·Axel Voigt
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Abstract

Convexity splitting like schemes with improved accuracy are proposed for a phase field model for surface diffusion. The schemes are developed to enable large scale simulations in three spatial dimensions describing experimentally observed solid state dewetting phenomena. We introduce a first and a second order unconditionally energy stable scheme and carefully elaborate the loss in accuracy associated with large time steps in such schemes. We then present a family of Rosenbrock convex splitting schemes. We show the existence of a maximal numerical timestep and demonstrate the increase of this maximal numerical time step by at least one order of magnitude using a Rosenbrock method. This scheme is used to study the effect of contact angle on solid state dewetting phenomena.

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Rainer Backofen, Steven M. Wise, Marco Salvalaglio, Axel Voigt. 2017-10-26. Convexity splitting in a phase field model for surface diffusion. https://arxiv.org/abs/1710.09675

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