Conference article

Modelling of complex thermal energy supply systems based on the Modelica-Library FluidFlow

Manuel Ljubijankic
Institute for Architecture and Urban Design, University of Arts Berlin, Germany

Christoph Nytsch-Geusen
Institute for Architecture and Urban Design, University of Arts Berlin, Germany \ Fraunhofer Institute for Computer Architecture and Software Technology, Germany

Steffen Unger
Fraunhofer Institute for Computer Architecture and Software Technology, Germany

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Published in: Proceedings of the 7th International Modelica Conference; Como; Italy; 20-22 September 2009

Linköping Electronic Conference Proceedings 43:37, s. 335-340

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Published: 2009-12-29

ISBN: 978-91-7393-513-5

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


The new Modelica library FluidFlow is being developed for the thermo-hydraulic simulation of complex energy supply systems. This library includes standard hydraulic model classes and specialized components for HVAC-systems and solar thermal systems. Most of these Modelica classes are modelled with equations of the 1Dtransient energy transport. The validation of the library takes place both by measuring values from test stations and by comparing with detailed CFD models. A first complex use case of the library represents the simulations-based design of a complex thermal energy supply system of a residential area; as a part of a newly built city in Iran.


Thermo-hydraulic simulation; validation with CFD; modelling of complex energy supply systems


[1] S. Fabricius; E. Badreddin: Modelica Library for Hybrid Simulation of Mass Flow in Process Plants. QSSFluidFlow. Proceedings 2th International Modelica Conference. DLR; München.18.-19. März 2002.

[2] F. Casella et al.: The Modelica Fluid and Media library for modeling of incompressible and compressible thermofluid pipe networks. Proceedings 5th International Modelica Conference. Arsenal Research; Wien. 4.-5. September 2006.

[3] M. Ljubijankic; C. Nytsch-Geusen: Thermohydraulische Simulation solar-thermischer Systeme mit Modelica. In Proceedings: 18. Symposium Thermische Solarenergie; OTTI-Technologiekolleg; Regensburg; 2008.

[4] C. Nytsch; M. Poli; T. Schneider: Messtechnische Untersuchungen an einer solarthermischen Versuchsanlage zur Validierung der solartechnischen Modelle der Simulationsumgebung SMILE. In Proceedings: 10. Symposium Thermische Solarenergie in Staffelstein; OTTI-Technologiekolleg; Regensburg; 2000.

[5] M. Ljubijankic; C. Nytsch-Geusen: Combining different levels of detail in modelling for an improved precision of HVAC plant simulation. In Proceedings: Building Simulation 2009; International Building Performance Simulation Association; Glasgow; 2009.

[6] W. Wagner: Strömung und Druckverlust. 6.; bearbeite Auflage; Vogelverlag; 2008

[7] Homepage of the research project “Young Cities”:

[8] B.M. Kari; R. Fayaz: Evaluation of the Iranian Thermal Building Code; in: Asian Journal of Civil Engineering (Building and Housing) pp. 675-684; p.683; Vol. 7; No. 6; 2006.

[9] Homepage CASANOVA: Code 19

[10] C. Nytsch-Geusen; T. Nouidui: Gebäudesimulation mit adaptiven Modellierungsansätzen. In Proceedings: BAUSIM 2008; IBPSA Germany; Universität Kassel; 2008.

[11] A. Kühn; M. G. Ribigini; F. Ziegler: Dynamisches Betriebsverhalten einer 10kW Absorptionskälteanlage. KI – Kälte-; Luft-; Klimatechnik 7-8/2006.

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