A physical solution for solving the zero-flow singularity in static thermal-hydraulics mixing models

Daniel Bouskela
EDF R&D, Chatou Cedex, France

Baligh El Hefni
EDF R&D, Chatou Cedex, France

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp14096847

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

Linköping Electronic Conference Proceedings 96:88, s. 847-855

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Publicerad: 2014-03-10

ISBN: 978-91-7519-380-9

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


For the 0D-1D modelling of thermalhydraulics systems; it is common practice to use static mixing models to compute the mixing specific enthalpy in fluid junctions such as mergers or splitters. However; this simplification leads to a well known singularity when the mass flow rate inside the junction goes to zero. The origin of the singularity is explained; and a rigorous physical solution is proposed to eliminate the singularity. A prototype implementation has been developed in the ThermoSysPro library for power plant modelling that illustrates the interest of the proposed solution and enables to evaluate the computing overhead with respect to several possible variants.


Thermal-hydraulics; mixing models; convection; diffusion; ThermoSysPro


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