Conference article

Modelica Library for Building Heating; Ventilation and Air-Conditioning Systems

Michael Wetter
Simulation Research Group, Building Technologies Department, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, USA

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

Linköping Electronic Conference Proceedings 43:44, s. 393-402

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Published: 2009-12-29

ISBN: 978-91-7393-513-5

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


This paper presents a freely available Modelica library for building heating; ventilation and air conditioning systems. The library is based on the Modelica.Fluid library. It has been developed to support research and development of integrated building energy and control systems. The primary applications are controls design; energy analysis and model-based operation.

The library contains dynamic and steady-state component models that are applicable for analyzing fast transients when designing control algorithms and for conducting annual simulations when assessing energy performance. For most models; dimensional analysis is used to compute the performance for operating points that differ from nominal conditions. This allows parameterizing models in the absence of detailed geometrical information which is often impractical to obtain during the conceptual design phase of building systems.

In the first part of this paper; the library architecture and the main classes are described. In the second part; an example is presented in which we implemented a model of a hydronic heating system with thermostatic radiator valves and thermal energy storage.


Building energy systems; heating; ventilation; air-conditioning; controls


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