Reduced order surrogate modeling technique for linear dynamic systems

Vahid Yaghoubi , Sadegh Rahrovani , Hassan Nahvi , Stefano Marelli (1, 2, 3)

1 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
2 GdR MASCOT-NUM - Méthodes d'Analyse Stochastique des Codes et Traitements Numériques
3 Chair of Risk, Safety and Uncertainty Quantification [ETH Zurich]

The availability of reduced order models can greatly decrease the computational costs needed for modeling, identification and design of real-world structural systems. However, since these systems are usually employed with some uncertain parameters, the approximant must provide a good accuracy for a range of stochastic parameters variations. The derivation of such reduced order models are addressed in this paper. The proposed method consists of a polynomial chaos expansion (PCE)-based state-space model together with a PCE-based modal dominancy analysis to reduce the model order. To solve the issue of spatial aliasing during mode tracking step, a new correlation metric is utilized. The performance of the presented method is validated through four illustrative benchmarks: a simple mass-spring system with four Degrees Of Freedom (DOF), a 2-DOF system exhibiting a mode veering phenomenon, a 6-DOF system with large parameter space and a cantilever Timoshenko beam resembling large-scale systems.

Domaines: Méthodologie [stat.ME]; Applications [stat.AP]

Vahid Yaghoubi, Sadegh Rahrovani, Hassan Nahvi, Stefano Marelli. Reduced order surrogate modeling technique for linear dynamic systems. Mechanical Systems and Signal Processing, 2018, 111, pp.172 - 193. ⟨10.1016/j.ymssp.2018.02.020⟩. ⟨hal-01893260⟩