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arXiv · 1401.6327

A Fourier Pseudospectral Method for the "Good" Boussinesq Equation with Second Order Temporal Accuracy

Kelong Cheng·Wenqiang Feng·Sigal Gottlieb·Cheng Wang
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Abstract

In this paper, we discuss the nonlinear stability and convergence of a fully discrete Fourier pseudospectral method coupled with a specially designed second order time-stepping for the numerical solution of the "good" Boussinesq equation. Our analysis improves the existing results presented in earlier literature in two ways. First, an $l_\infty(0, T^*; H2)$ convergence for the solution and $l_\infty(0, T^*; l_2)$ convergence for the time-derivative of the solution are obtained in this paper, instead of the $l_\infty(0, T^*; l_2)$ convergence for the solution and the $l_\infty(0, T^*; H^{-2})$ convergence for the time-derivative, given in [17]. In addition, the stability and convergence of this method is shown to be unconditional for the time step in terms of the spatial grid size, compared with a severe restriction time step restriction $\Delta t \leq Ch^2$ reported in [17].

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Kelong Cheng, Wenqiang Feng, Sigal Gottlieb, Cheng Wang. 2014-01-24. A Fourier Pseudospectral Method for the "Good" Boussinesq Equation with Second Order Temporal Accuracy. https://arxiv.org/abs/1401.6327

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