Detecting internal resonances during model reduction

Model order reduction of geometrically nonlinear dynamic structures is often achieved via a static condensation procedure, whereby high-frequency modes are assumed to be quasi-statically coupled small set lower frequency modes, which form the basis. This approach mathematically justifiable for characterized by slow/fast dynamics, such as thin plates and slender beams, has been shown provide highly accurate results. Nevertheless, selecting basis without priori knowledge full-order dynamics challenging task; retaining redundant will lead computationally suboptimal reduced-order models (ROMs), while omitting dynamically significant inaccurate results, important features internal resonances may not captured. In this study, we demonstrate how error associated with can efficiently approximated during model reduction. approximate then used method predicting when modal interactions occur, guide selection process. Equivalently, serve tool verifying accuracy ROMs need simulations. The proposed demonstrated using simple oscillator finite element clamped–clamped beam.