Summary
Finite element models with fine spatial discretization are required for accurate predictions of vibration-induced stresses which can cause fatigue. Dynamic analyses with these models, however, come at high computational cost. Therefore, many applications, e.g., such requiring large parameter studies, are prohibitive. Although many techniques for model order reduction have been developed, most of them are not applicable to the combination of geometric and contact nonlinearities. We present a novel dynamic substructuring approach for thin-walled jointed structures which divides the assembly into thin-walled substructures with geometric nonlinearites and geometrically linear substructures featuring contact nonlinearity. Each class of substructures is then reduced using adapted variants of Component Mode Synthesis. Moreover, interface reduction is applied to the substructure interface. The accuracy of the re-assembled reduced-order model was shown in quasi-static and transient dynamic analyses performed on a benchmark structure. Also, the importance of both types of nonlinearity was demonstrated. The method was able to reduce the computation times by orders of magnitude in the dynamic analyses.
