Conference article

Numerical coupling of Modelica and CFD for building energy supply systems

Manuel Ljubijankic
Universität der Künste Berlin, Lehrstuhl für Versorgungsplanung und Versorgungstechnik, Germany

Christop Nytsch-Geusen
Universität der Künste Berlin, Lehrstuhl für Versorgungsplanung und Versorgungstechnik, Germany

Jörg Rädler
Universität der Künste Berlin, Lehrstuhl für Versorgungsplanung und Versorgungstechnik, Germany

Martin Löffler
TLK-Thermo GmbH, Germany

Download article

Published in: Proceedings of the 8th International Modelica Conference; March 20th-22nd; Technical Univeristy; Dresden; Germany

Linköping Electronic Conference Proceedings 63:32, s. 286-294

Show more +

Published: 2011-06-30

ISBN: 978-91-7393-096-3

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


This paper presents an integrated method for the simulation of mixed 1D / 3D system models in the domain of building energy supply systems. The feasibility of this approach is demonstrated by the use case of a solar thermal system: the sub-model of a hot water storage is modeled as a detailed threedimensional CFD model; but the rest of the system model (solar collector; hydraulics; heat exchanger; controller etc.) is modeled as a simplified component-based DAE model. For this purpose; the hot water storage model is simulated with ANSYS CFD. This detailed sub-model is embedded in the solar thermal system model; which consists of component models of the Modelica library FluidFlow and is simulated with Dymola. The numerical coupling and integration of both sub-models is realized by the use of the co-simulation environment TISC. With a comparison of a pure Modelica system model and a mixed 1D / 3D system model of the same solar thermal system; advantages and disadvantages of both simulation approaches are worked out.


Co-simulation; Mixed 1D/3D modeling; energy building and plant simulation


[1] Homepage Modelica Association:

[2] Homepage MATLAB/Simulink: http://

[3] Homepage TRNSYS:

[4] M. Ljubijankic; C. Nytsch-Geusen: Thermohydraulische Simulation solarthermischer Systeme mit Modelica. In Proceedings: 18. Symposium Thermische Solarenergie; OTTITechnologiekolleg; Regensburg; 2008.

[5] Homepage ncDataReader:

[6] Ederer; K.; Huber; J.; Nytsch-Geusen; C.; Seelig; S.; Unger; S.; Wehage; P.: Konzeption und Planung solarunterstützter Energieversorgungssysteme für New Towns im Iran. In Tagungsband: 20. Symposium Thermische Solarenergie in Staffelstein; OTTITechnologiekolleg; Regensburg; 2010.

[7] 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.

[8] Homepage Dymola:

[9] Homepage ANSYS CFD:

[10] Kossel; R.; Tegethoff; W.; Bodmann; M.; Lemke; N.: Simulation of Complex Systems using Modelica and Tool Coupling. In: Proceedings of the 5th International Modelica Conference; Vienna; Austria; Modelica Association; September 2006; 485 – 490.

[11] Kossel; R.; Försterling; S.; Tegethoff; W.: Einsatz hybrider Simulationstechnik für die Bewertung mobiler Heiz- und Kühlkonzepte. In: Brill; U. (Hrsg.) ; Haus der Technik (Veranst.): Wärmemanagement des Kraftfahrzeugs VI Haus der Technik; Expert-Verlag; Juni 2008 (Haus der Technik Fachbuch 93). – ISBN 978–3–8169–2820–1; S. 150 – 162.

[12] Kossel; R.; Correia; C.; Loeffler; M.; Bodmann; M. ; Tegethoff; W.: Verteilte Systemsimulation mit TISC. In: ASIMWorkshop 2009 in Dresden mit integrierter DASS’2009; 2009.

[13] W. Puntigam et al.; Transient Co-Simulation of Comprehensive Vehicle Models by Time Dependent Coupling. In: SAE 2006 Transaction Journal of Passenger Cars: Mechanical Systems; ISBN 978-0-7680-1838-7; pages 1516 - 1525.

[14] M. Ljubijankic; C. Nytsch-Geusen; S. Unger: Modelling of complex thermal energy supply systems; based on the Modelica-Library FluidFlow. Proceedings 6th International Modelica Conference. In Proceedings: 7th International Modelica Conference; 20./22. September; Como; 2009.

[15] 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.

[16] Homepage Meteonorm:

Citations in Crossref