467
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IGPM467.pdf July 2017 |
TITLE |
Asymptotic Error Analysis of an IMEX Runge-Kutta method |
AUTHORS |
Klaus Kaiser, Jochen Schütz |
ABSTRACT |
We consider a system of singularly perturbed differential equations with singular parameter
ε<<1, discretized with an IMEX Runge-Kutta method. The splitting needed for the IMEX method stems from a linearization of the fluxes around the limit solution. We analyze the asymptotic convergence order as
ε→0. We show that in this setting, the minimal stage order of the implicit part of the scheme is of great importance, thereby explaining earlier numerical results showing a close correlation of errors of the splitting scheme and the fully implicit one. |
KEYWORDS |
Order reduction, RS-IMEX, IMEX Runge-Kutta, singularly perturbed equation, asymptotic convergence order |