Numerical Instability of Classical Free-Interface Component Mode Synthesis Techniques

International audienceFinite element based component mode synthesis (CMS) techniques are popular tools used in structural dynamics applications.In CMS, the original structure is subdivided into smaller substructures, or components, for which normal modes are computed independently and more inexpensively. The assembled system is then represented by a truncated set of component modes through necessary compatibility constraints applied in a systematic fashion. This process yields reduced-order models based on parent finite element models of arbitrary complexity. CMS techniques are usually characterized by the manner in which the component normal modes are computed:1) with fixed interfaces or 2) with free interfaces