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Title: IMEX methods for thin-film equations and Cahn–Hilliard equations with variable mobility
We explore a class of splitting schemes employing implicit-explicit (IMEX) time-stepping to achieve accurate and energy-stable solutions for thin-film equations and Cahn-Hilliard models with variable mobility. This splitting method incorporates a linear, constant coefficient implicit step, facilitating efficient computational implementation. We investigate the influence of stabi- lizing splitting parameters on the numerical solution computationally, considering various initial conditions. Furthermore, we generate energy-stability plots for the proposed methods, examin- ing different choices of splitting parameter values and timestep sizes. These methods enhance the accuracy of the original bi-harmonic-modified (BHM) approach, while preserving its energy- decreasing property and achieving second-order accuracy. We present numerical experiments to illustrate the performance of the proposed methods.  more » « less
Award ID(s):
2008255
PAR ID:
10515150
Author(s) / Creator(s):
;
Publisher / Repository:
arXiv:2405.19483
Date Published:
Journal Name:
Computational Materials Science
Volume:
243
Issue:
C
ISSN:
0927-0256
Page Range / eLocation ID:
113145
Subject(s) / Keyword(s):
Cahn-Hilliard equation thin film equation IMEX time-stepping schemes implicit-explicit methods variable mobility
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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