# IFOSMONDI: A Generic Co-simulation Approach Combining Iterative Methods for Coupling Constraints and Polynomial Interpolation for Interfaces Smoothness

### Yohan Éguillon, Bruno Lacabanne, Damien Tromeur-Dervout

#### Abstract

This paper introduces IFOSMONDI co-simulation algorithm that combines iterative coupling methods and a smooth representation of interface variables. In explicit (i.e. non-iterative) coupling methods, representing smooth interface variables requires the introduction of a delay (Busch, 2016) because the values of the interface variables at the end of a given macro-step are not known when the co-simulation only reached the beginning of this very macro-step. One of the advantages of implicit co-simulation (i.e. iterative coupling methods) is that the values of the interface variables can be known at the end of a macro-step with the possibility to replay the integration on this very macro-step. Combining this with a polynomial representation of the interface variables enables to use interpolation instead of extrapolation across the macro-steps (Kübler and Schiehlen, 2000). Taking into account time-derivatives of interface variables makes it possible to ensure C1 smoothness even with no history of the past exchanged data: then, no delay is introduced. A new possibility then arises: the solvers of each subsystem may take into account this smoothness and be less restrictive on their restarts due to the communication times. The results obtained on the test case of the two mass oscillators (Busch, 2016) show the advantage of IFOSMONDI coupling in terms of trade-off between elapsed time and accuracy.

Download#### Paper Citation

#### in Harvard Style

Éguillon Y., Lacabanne B. and Tromeur-Dervout D. (2019). **IFOSMONDI: A Generic Co-simulation Approach Combining Iterative Methods for Coupling Constraints and Polynomial Interpolation for Interfaces Smoothness**.In *Proceedings of the 9th International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,* ISBN 978-989-758-381-0, pages 176-186. DOI: 10.5220/0007977701760186

#### in Bibtex Style

@conference{simultech19,

author={Yohan Éguillon and Bruno Lacabanne and Damien Tromeur-Dervout},

title={IFOSMONDI: A Generic Co-simulation Approach Combining Iterative Methods for Coupling Constraints and Polynomial Interpolation for Interfaces Smoothness},

booktitle={Proceedings of the 9th International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,},

year={2019},

pages={176-186},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0007977701760186},

isbn={978-989-758-381-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 9th International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,

TI - IFOSMONDI: A Generic Co-simulation Approach Combining Iterative Methods for Coupling Constraints and Polynomial Interpolation for Interfaces Smoothness

SN - 978-989-758-381-0

AU - Éguillon Y.

AU - Lacabanne B.

AU - Tromeur-Dervout D.

PY - 2019

SP - 176

EP - 186

DO - 10.5220/0007977701760186