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arXiv · 2303.00222

Efficient and accurate exponential SAV algorithms with relaxation for dissipative system

Yanrong Zhang·Xiaoli Li
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Abstract

In this paper, we construct two kinds of exponential SAV approach with relaxation (R-ESAV) for dissipative system. The constructed schemes are linear and unconditionally energy stable. They can guarantee the positive property of SAV without any assumption compared with R-SAV and R-GSAV approaches, preserve all the advantages of the ESAV approach and satiesfy dissipation law with respect to a modified energy which is directly related to the original free energy. Moreover the second version of R-ESAV approach is easy to construct high-order BDF$k$ schemes. Especially for Navier-Stokes equations, we construct wo kinds of novel schemes based on the R-ESAV method. Finally, ample numerical examples are presented to exhibit that the proposed approaches are accurate and effective.

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Yanrong Zhang, Xiaoli Li. 2023-03-01. Efficient and accurate exponential SAV algorithms with relaxation for dissipative system. https://arxiv.org/abs/2303.00222

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