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arXiv · 2505.15985

Fast-wave slow-wave spectral deferred correction methods applied to the compressible Euler equations

Alex Brown·Joscha Fregin·Thomas Bendall·Thomas Melvin·Daniel Ruprecht·Jemma Shipton
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Abstract

This paper investigates the application of a fast-wave slow-wave spectral deferred correction time-stepping method (FWSW-SDC) to the compressible Euler equations. The resulting model achieves arbitrary order accuracy in time, demonstrating robust performance in standard benchmark idealised test cases for dynamical cores used for numerical weather prediction. The model uses a compatible finite element spatial discretisation, achieving good linear wave dispersion properties without spurious computational modes. A convergence test confirms the model's high temporal accuracy. Arbitrarily high spatial-temporal convergence is demonstrated using a gravity wave test case. The model is further extended to include the parametrisation of a simple physics process by adding two phases of moisture and its validity is demonstrated for a rising thermal problem. Finally, a baroclinic wave in simulated in a Cartesian domain.

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Alex Brown, Joscha Fregin, Thomas Bendall, Thomas Melvin, Daniel Ruprecht, Jemma Shipton. 2025-05-21. Fast-wave slow-wave spectral deferred correction methods applied to the compressible Euler equations. https://arxiv.org/abs/2505.15985

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