Conference article

Steady-state initialization of object-oriented thermo-fluid models by homotopy methods

Francesco Casella
Dipartimento di Elettronica e Informazione, Politecnico di Milano, Italy

Michael Sielemanny
Deutsches Zentrum für Luft- und Raumfahrt, Institute of Robotics and Mechatronics, Germany

Luca Savoldelli
Dipartimento di Elettronica e Informazione, Politecnico di Milano, Italy

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

Linköping Electronic Conference Proceedings 63:11, p. 86-96

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Published: 2011-06-30

ISBN: 978-91-7393-096-3

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


The steady-state initialization of large object-oriented thermo-hydraulic networks is a difficult problem; because of the sensitivity of the convergence to the initial guesses of the iteration variables. This paper proposes an approach to this problem based on homotopy transformation; detailing specific criteria for model simplifications in this physical domain. The approach is successfully demonstrated on large power plant test cases; having several hundreds of iteration variables.


Thermo-hydraulic systems; power plants; steady-state initialization problems


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