Conference article

Validation Techniques Applied on the Saab Gripen Fighter Environmental Control System Model

Robert Hällqvist
Saab Aeronautics, Linköping, Sweden

Magnus Eek
Saab Aeronautics, Linköping, Sweden

Ingela Lind
Saab Aeronautics, Linköping, Sweden

Hampus Gavel
Saab Aeronautics, Linköping, Sweden

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Published in: Proceedings of the 56th Conference on Simulation and Modelling (SIMS 56), October, 7-9, 2015, Linköping University, Sweden

Linköping Electronic Conference Proceedings 119:20, s. 199-210

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Published: 2015-11-25

ISBN: 978-91-7685-900-1

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


The Environmental Control System (ECS) of the Saab Gripen fighter provides a number of vital functions, such as provision of coolant air to the avionics, comfort air to the cockpit, and pressurization of the aircraft fuel system. To support system design, a detailed simulation model has been developed in the Modelica-based tool Dymola. The model needs to be a “good system representation”, during both steady-state operation and relevant dynamic events, if reliable predictions are to be made regarding cooling performance, static loads in terms of pressure and temperature, and various other types of system analyses. A framework for semi-automatic validation of the ECS model against measurements is developed and described in this paper. Applied methods for validating the model in steady-state operation and during relevant dynamic events are presented in detail. The developed framework includes automatic filtering of measurement points defined as steady-state operation and visualization techniques applied on validation experiments conducted in the previously mentioned points. The proposed framework both simplify continuous validation throughout the system development process and enables a smooth transition towards a more independent verification and validation process.


Verification and Validation; Coverage; Domain of Validity; Historical Data Validation


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