Model order reduction in unit cell modeling and its application to complex structures

© Proceedings of ISMA 2018 - International Conference on Noise and Vibration Engineering and USD 2018 - International Conference on Uncertainty in Structural Dynamics. All rights reserved. In this work, harmonic and temporal responses of structures composed of 1D periodic waveguides are computed using the wave finite element method framework (WFEM) in conjunction with model order reduction (MOR) methods. First, a model order reduction strategy at the unit cell level is introduced and extended to parametric model order reduction (PMOR) when the mesh does not depend of the interfaces. The method relies on a mode based MOR of the inner degrees of freedom of the unit cell combined with a wave based model order reduction of the interfaces' degrees of freedom by projecting them on a collection of wave shapes obtained through the inverse approach. A first example analyses the merits of the proposed PMOR. A second example exploits the MOR method to analyze guided-waves interactions with a 3D defect in the mid-frequency domain. The proposed methodology enables the computation of highly complex and detailed models while providing substantial time reduction when computations were already possible.status: publishe