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arXiv · 2308.16736

Operator splitting for semi-explicit differential-algebraic equations and port-Hamiltonian DAEs

Abstract

Operator splitting methods allow to split the operator describing a complex dynamical system into a sequence of simpler subsystems and treat each part independently. In the modeling of dynamical problems, systems of (possibly coupled) differential-algebraic equations (DAEs) arise. This motivates the application of operator splittings which are aware of the various structural forms of DAEs. Here, we present an approach for the splitting of coupled index-1 DAE as well as for the splitting of port-Hamiltonian DAEs, taking advantage of the energy-conservative and energy-dissipative parts. We provide numerical examples illustrating our second-order convergence results.

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Andreas Bartel, Malak Diab, Andreas Frommer, Michael Günther. 2023-08-31. Operator splitting for semi-explicit differential-algebraic equations and port-Hamiltonian DAEs. https://arxiv.org/abs/2308.16736

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