Simulation Speed Analysis and Improvements of Modelica Models for Building Energy Simulation

Filip Jorissen
Mechanical Engineering, KU Leuven, Leuven, Belgium / EnergyVille, Waterschei, Belgium

Michael Wetter
Energy Technologies Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

Lieve Helsen
Mechanical Engineering, KU Leuven, Leuven, Belgium / EnergyVille, Waterschei, Belgium

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp1511859

Ingår i: Proceedings of the 11th International Modelica Conference, Versailles, France, September 21-23, 2015

Linköping Electronic Conference Proceedings 118:6, s. 59-69

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Publicerad: 2015-09-18

ISBN: 978-91-7685-955-1

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


This paper presents an approach for speeding up Modelica models. Insight is provided into how Modelica models are solved and what determines the tool’s computational speed. Aspects such as algebraic loops, code efficiency and integrator choice are discussed. This is illustrated using simple building simulation examples and Dymola. Using this approach a medium sized office building including building envelope, heating ventilation and air conditioning (HVAC) and control strategy can be simulated at a speed five hundred times faster than real time.


Modelica; speed; performance; buildings; solver; integrator


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