Advanced Hybrid Model for Borefield Heat Exchanger Performance Evaluation; an Implementation in Modelica

Damien Picard
KU Leuven, Department of Mechanical Engineering, Division of Applied Mechanics and Energy Conversion, Heverlee, Belgium

Lieve Helsen
KU Leuven, Department of Mechanical Engineering, Division of Applied Mechanics and Energy Conversion, Heverlee, Belgium

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp14096857

Ingår i: Proceedings of the 10th International Modelica Conference; March 10-12; 2014; Lund; Sweden

Linköping Electronic Conference Proceedings 96:89, s. 857-866

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Publicerad: 2014-03-10

ISBN: 978-91-7519-380-9

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


Accurate and computationally efficient borefield models are important components in building energy simulation programs. They have not been implemented in Modelica so far. This paper describes the implementation of an innovative approach to model borefields with arbitrary configuration having both shortterm (minutes) and long-term accuracy (decades) into Modelica. A step response is calculated using a combination of a short-term response model which takes into account the transient heat transfer in the heat carrier fluid; the grout and the immediately surrounding ground; and a long-term response model which calculates the boreholes interactions. Moreover; an aggregation method is implemented to speed up the calculations. Validation shows good results and very high computational efficiency.


Borefield; short- and long-term; Modelica; Aggregation method


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