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arXiv · 1903.03342

Model order reduction of hyperbolic systems at the example of district heating networks

Markus Rein·Jan Mohring·Tobias Damm·Axel Klar
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Abstract

In this article a framework for the generation of a computationally fast surrogate model for district heating networks is presented. An appropriate model results in an index-1 hyperbolic, differential algebraic equation quadratic in state, exhibiting several hundred of outputs to be approximated. We show the existence of a global energy matrix which fulfills the Lyapunov inequality ensuring stability of the reduced model. By considering algebraic variables as parameters to the dynamical transport, the reduction of a linear, time varying (LTV) problem results. We present a scheme to efficiently combine linear reductions to a global surrogate model using a greedy strategy in the frequency domain. The numerical effectiveness of the scheme is demonstrated at different, existing, large scale networks.

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Markus Rein, Jan Mohring, Tobias Damm, Axel Klar. 2019-03-08. Model order reduction of hyperbolic systems at the example of district heating networks. https://arxiv.org/abs/1903.03342

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