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arXiv · 2105.03930

Arbitrary high-order linear structure-preserving schemes for the regularized long-wave equation

Chaolong Jiang·Xu Qian·Songhe Song·Jin Cui
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Abstract

In this paper, a class of arbitrarily high-order linear momentum-preserving and energy-preserving schemes are proposed, respectively, for solving the regularized long-wave equation. For the momentum-preserving scheme, the key idea is based on the extrapolation/prediction-correction technique and the symplectic Runge-Kutta method in time, together with the standard Fourier pseudo-spectral method in space. We show that the scheme is linear, high-order, unconditionally stable and preserves the discrete momentum of the system. For the energy-preserving scheme, it is mainly based on the energy quadratization approach and the analogous linearized strategy used in the construction of the linear momentum-preserving scheme. The proposed scheme is linear, high-order and can preserve a discrete quadratic energy exactly. Numerical results are addressed to demonstrate the accuracy and efficiency of the proposed scheme.

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Chaolong Jiang, Xu Qian, Songhe Song, Jin Cui. 2021-05-09. Arbitrary high-order linear structure-preserving schemes for the regularized long-wave equation. https://arxiv.org/abs/2105.03930

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