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

TL;DR

This paper introduces high-order linear schemes that preserve momentum and energy for the regularized long-wave equation, combining spectral methods with symplectic integrators and energy quadratization.

Contribution

It develops novel linear, high-order, structure-preserving schemes for the regularized long-wave equation, ensuring stability and conservation properties.

Findings

Schemes are linear, high-order, and unconditionally stable.

The momentum-preserving scheme uses extrapolation and symplectic Runge-Kutta methods.

The energy-preserving scheme exactly conserves a discrete quadratic energy.

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.