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DOE OSTI · 1883232

Implicit extensions of an explicit multirate Runge–Kutta scheme

Constantinescu, Emil M.
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Abstract

In this work, we propose a new method that extends conservative explicit multirate methods to implicit explicit-multirate methods. We develop extensions of order one and two with different stability properties on the implicit side. The method is suitable for time-stepping adaptive mesh refinement PDE discretizations with different degrees of stiffness. A numerical example with an advection-diffusion problem illustrates the new method's properties.

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97 MATHEMATICS AND COMPUTINGAdaptive mesh refinementIMEX, partitioned Runge–KuttaMultirate time-steppingRunge–Kutta

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Constantinescu, Emil M.. 2021-12-29. Implicit extensions of an explicit multirate Runge–Kutta scheme. https://doi.org/10.1016/j.aml.2021.107871

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