Conference article

Integrated Thermal Management Simulation: Evaluating the Effect of Underhood Recirculation Flows on AC-System Performance

Zhu Wang
Exa Corporation, USA

Kristian Tuszynski
Modelon AB, Ideon Science Park, Lund, Sweden Ideon Science Park, Lund, Sweden

Hubertus Tummescheit
Modelon AB, Ideon Science Park, Lund, Sweden

Ales Alajbegovic
Exa Corporation, USA

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

Linköping Electronic Conference Proceedings 43:46, s. 413-422

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Published: 2009-12-29

ISBN: 978-91-7393-513-5

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


Presented is a model for the simulation of the interaction between the airflow and the AC-system. Demonstrated is 1) a successful coupling of flow solver (PowerFLOW 4.1) with the Modelica-based Dymola system tool and the AirConditioning Library; making use of the previously validated underhood-environment; and 2) the importance of a careful design of the underhood flow for the AC-system performance. The validity of the developed simulation capability is tested by successful comparison with the available experimental data for the condenser at the given operating conditions. Shown is the potential for the analysis of the flow details and structures affecting the condenser performance like airflow recirculation.


HVAC simulation; underhood flow; simulator coupling


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